2007 venezia, congresso mondiale, ablazione delle tachicardie ventricolari
2005 gubbio, workshop interattivo, la stimolazione cardiaca convenzionale e quella multisito
1. ““ Stimolazione Convenzionale e Multisito “Stimolazione Convenzionale e Multisito “
Gubbio 2005Gubbio 2005
Stefano Nardi, MD
AZIENDA OSPEDALIERA SANTA MARIA TERNIAZIENDA OSPEDALIERA SANTA MARIA TERNI
DIPARTIMENTO CARDIOTORACOVASCOLAREDIPARTIMENTO CARDIOTORACOVASCOLARE
STRUTTURA COMPLESSA DI CARDIOLOGIASTRUTTURA COMPLESSA DI CARDIOLOGIA
STRUTTURA SEMPLICE DI ARITMOLOGIASTRUTTURA SEMPLICE DI ARITMOLOGIA
LABORATORIO DI ELETTROFISIOLOGIA ED ELETTROSTIMOLAZIONELABORATORIO DI ELETTROFISIOLOGIA ED ELETTROSTIMOLAZIONE
2. Fibrillazione Atriale CronicaFibrillazione Atriale Cronica
o Atrio Silenteo Atrio Silente
Fibrillazione Atriale CronicaFibrillazione Atriale Cronica
o Atrio Silenteo Atrio Silente
Tachiaritmie AtrialiTachiaritmie Atriali
IntermittentiIntermittenti
Tachiaritmie AtrialiTachiaritmie Atriali
IntermittentiIntermittenti
Pacing VentricolarePacing Ventricolare
Normale o bradicardia sinusaleNormale o bradicardia sinusaleNormale o bradicardia sinusaleNormale o bradicardia sinusale
La Conduzione AV è adeguata ?La Conduzione AV è adeguata ?La Conduzione AV è adeguata ?La Conduzione AV è adeguata ?
DDDRDDDRDDDRDDDR DDDDDDDDDDDD
AAIRAAIRAAIRAAIR AAIAAIAAIAAI
La Frequenza cardiacaLa Frequenza cardiaca
incrementaincrementa
adeguatamenteadeguatamente
con l’esercizio?con l’esercizio?
SincroniaSincronia
AVAV
SS
NN
NN
SS
NN
SS
AnormaleAnormaleAnormaleAnormale
La Conduzione AV è adeguata ?La Conduzione AV è adeguata ?La Conduzione AV è adeguata ?La Conduzione AV è adeguata ?
SS
NN
La Frequenza cardiacaLa Frequenza cardiaca
incrementa adeguatamenteincrementa adeguatamente
con l’esercizio?con l’esercizio?
SS NN
DDD(R)*DDD(R)*
DDI(R)DDI(R)
DDD(R)*DDD(R)*
DDI(R)DDI(R)
DDDR*DDDR*
DDIRDDIR
DDDR*DDDR*
DDIRDDIR
VVI oVVI o
VVIRVVIR
VVI oVVI o
VVIRVVIR
La Frequenza cardiacaLa Frequenza cardiaca
incrementa adeguatamenteincrementa adeguatamente
con l’esercizio?con l’esercizio?
Qual è la condizioneQual è la condizione
dell’atrio?dell’atrio?
* = Con algoritmo di cambio di modo automatico in caso di SVT* = Con algoritmo di cambio di modo automatico in caso di SVT
Albero decisionale del modo di
stimolazione ottimale
3. • Alterata MECCANICA Ventricolo Sinistro
• La maggioranza dei pazienti (~77%) con SSS,
compresi quelli CHF conduzione AV intatta e
QRS stretto (attivazione ventricolare normale).6
• RVA pacing simula LBBB, con un conseguente
QRS allargato, desincronizzazione ventricolare,
ed alterazione struttura e funzione
ventricolare.6,7
• Desincronizzazione “forzata” per RVA pacing
aumenta il rischio di FA, CHF & decesso.1,4-6
4. Danish II Trial1
AAI(R)
vs
DDD(R) con AV corto
vs
DDD(R) con AV lungo
CTOPP Trial4
DDD(R) or
AAI(R)
vs
VVI(R)
DAVID Trial5
DDD(R)
vs
VVI ICDs
MOST Substudy6
DDDR
vs
VVIR
Ospedaliz.
per HF
Non specificatamente
misurata; lo studio indica
che un’alta % di stim.RV
riduce la funzione LV
Non misurata 1 anno senza eventi
(decesso o
osped.per HF) era
peggiore nel
gruppo DDDR con
%VP > 40%
Incremento di 2.6
volte del rischio
quando %VP > 40%
(gruppo DDDR)
Performance
Emodinamica
La stim. DDDR a lungo
termine provoca dilatazione
LA e un’alta % di stim.RV
riduce la funzione LV
Pazienti con
intatta
funzione LV,
storia negativa
per MI o CAD
traggono il
maggior
beneficio dalla
stimolazione
fisiologica
Non misurata Supporta la
conclusione che la
dissincronia V
imposta dalla
stimolazione V
destra può essere
deleteria in pazienti
con ridotta funzione
del ventricolo
sinistroIncidenza di
AF
L’assenza di AF ai controlli
è significativamente
migliore con la
stimolazione AAIR
(p = 0.03);
17% stim. RV nel gruppo
La stimolazione
fisiologica
riduce la
probabilità di
sviluppare AF
cronica
Non misurata Rischio aumentato
linearmente dell’1%
per ogni 1% di
aumento della
stim.V
(fino all’ ~ 85%)
5. 0
1
2
3
4
0 20 40 60 80 100
Cum% VP
RiskofAFrelativeto
DDDRpatientwithCum%VP=0
0
1
2
3
4
0 20 40 60 80 100
Cum % VP
RiskofAFrelativeto
VVIRpatientwithCum%VP=0
Sweeney MO, et al. Circulation 2003;23:2932-2937
Sottostudio MOSTMOST: la % cumulativa di stimolazione
ventricolare predice lo sviluppo di FA
• Il rischio di FA aumenta linearmente con la %
cumulativa di stim.V, fino a circa 80-85% sia nel
gruppo DDDR che in quello VVIR
• Il rischio di AF è ridotto dell’ 1% per ogni 1% di
diminuzione del Cum %VP nel gruppo DDDR.
Rischio Relativo - Studio MOST
6. Sottostudio MOST: DDDR vs VVIR, %VP e rischio
di prima osped. per HF
• Il RISCHIO RELATIVORISCHIO RELATIVO per la prima osped. per
HF è sempre maggiore per pazienti VVIR rispetto a
DDDR, indipendentemente dalla % di stimolazione
0
2
4
6
8
10
12
0- 20 20- 30 30- 40 > 40
Cum% VP
RiskofHFH
DDDR
VVIR
Sweeney MO, et al. Circulation 2003;23:2932-2937
Rischio Relativo - Studio MOST
7. 0
1
2
3
4
5
6
7
0 20 40 60 80 100
Cum % VP
RiskofHFHrelativeto
DDDRpatientwithCum%VP=0
Sweeney MO, et al. Circulation 2003;23:2932-2937
Sottostudio MOST: modo DDDR, % cumulativa di
stim.V e rischio di prima ospedalizzazione per CHF.
• Il rischio di ospedalizzazione per HF aumenta tra
0% e 40% di Cum VP, ma il rischio si stabilizza sopra
il 40% di Cum VP
• Il rischio è ridotto a circa il 2% se VP è minimizzata
Rischio Relativo - Studio MOST
8. 0
1
2
3
4
5
6
7
0 20 40 60 80 100
Cum% VP
RiskofHFHrelativeto
DDDRpatientwithCum%VP=0
Sweeney MO, et al. Circulation 2003;23:2932-2937
Sottostudio MOSTMOST: modo DDDR, Cum %VP e rischio di prima
ospedalizzazione per HF
Quando stimolazione V > 40%: Il rischio relativo per i
pazienti rimane pressochè costante e aumenta di 2.6 volte
rispetto a pazienti con stimolazione V > 40%
(es. con stim.V al 45% si ha lo stesso rischio relativo di
65%)
• Quando stimolazione V < 40%:
Per ogni 10% di riduzione nella % di stimolazione V.
c’è una diminuzione relativa del 54% del rischio di prima
ospedalizzaz.per HF
Rischio Relativo - Studio MOST
9. • il modo DDD/R è migliore del VVI/R per gli esiti
clinici a lungo termine6
– riduzione del rischio relativo per incidenza di
AF
– riduzione del rischio relativo per
ospedalizzazione per scompenso cardiaco
• la stimolazione “fisiologica” AAI/R è migliore
della stimolazione DDD/R quando la % di
stimolazione è alta.1,6
10. Incidence of Heart Failure
AnnualRateper1000
30-39 40-49 50-59 60-69 70-79 80-89
Age
Ho KL et al. JACC 1993
0
5
10
15
20
25
30
men
women
Conventional & Multisite PacingConventional & Multisite Pacing
14. 1 Framingham Heart Study (1948 – 1988) in Atlas of Heart Diseases.
2 American Heart Association. Heart Disease and Stroke Statistics—2003 Update.
CHF Patients Survival ResultsCHF Patients Survival Results11
100
90
80
70
60
50
40
30
20
10
0
Probabilityofsurvival,%
Men (Men (nn = 237)= 237)
Women (Women (nn = 230)= 230)
Time after CHF diagnosis, years
0 2 4 6 8 10
80% of men and 70%
of women who have
CHF will die within 8
years.2
80% of men and 70%
of women who have
CHF will die within 8
years.2
Conventional & Multisite PacingConventional & Multisite Pacing
15. • Reduced LVEF remains the single most important
risk factor for overall mortality and SCD.1
• Increased risk is measurable at LVEF 30%, but a
LVEF < 30% is the single most powerful
independent predictor for SCD.2
1
Prior SG, Aliot E, Blonstrom-Lundqvist C, et al. Task Force on Sudden Cardiac Death of the European Society of
Cardiology. Eur Heart J, Vol. 22; 16; August 2001.
2
Myerburg RJ, Castellanos A. Cardiac Arrest and Sudden Cardiac Death, in Braunwald E, Zipes DP, Libby P, Heart
Disease, A textbook of Cardiovascular Medicine. 6th
ed. 2001. W.B. Saunders, Co., p. 895.
Relationship of SCDRelationship of SCD
and LV Dysfunctionand LV Dysfunction
Conventional & Multisite PacingConventional & Multisite Pacing
16. Prognosis with
Ventricular
Dyssynchrony
Long-term (45 Mo)
Survival
34%
49%
QRS <
120 ms
QRS >
120 ms
Iuliano et al. AHJ 2002
N=669
P < 0.001
1 Year Survival
11%
16%
QRS <
120 ms
QRS >
120 ms
P < 0.001
Baldasseroni S. EHJ 2002
N=5,517
Conventional & Multisite PacingConventional & Multisite Pacing
17. Prevalence of VentricularPrevalence of Ventricular
Dyssynchrony in HFDyssynchrony in HF
Left Bundle Branch Block More Prevalent
with Impaired LV Systolic Function
38%
24%
8%
Moderate/Severe
HF (2)
Impaired LVSF
(1)
Preserved LVSF
(1)
1. Masoudi, et al. JACC 2003;41:217-23
2. Aaronson, et al. Circ 1997;95:2660-7
18. Deleterious Effects of Ventricular
Dyssynchrony on
Cardiac Function
Reduced diastolic filling
time 1
+
Weakened contractility 2
+
Protracted mitral
regurgitation 2
+
Post systolic regional
contraction 3
=
Diminished stroke volume 1. Grines CL, et al Circulation 1989
2. Xiao HB, et al Br Heart J 1991
3. Søgaard P, et al. J Am Coll Cardiol 2002
Courtesy of Ole-A. Breithardt, MD
21. the Cardiac Cycle time
Pressure
mmHg100100
5050
Systolic BP
Diastolic BP
What Happens in the Aorta?
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
24. LBBB
LABB +
Incomplete LBBB
NO LBBB
25.2%
67.9.%
6.9%
0
2000
4000
6000
8000
5517
3476
1771
TOTAL POPULATION
NO LBBB
LBBB + LABB +imcomplete LBBB
n°
Prevalence of wide QRS and LBBB in the
Study population (N°=5517)
INCHF
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
25. %
Mortality rate in patients with or
without LBBB
0
5
10
15
20
25
30
1 Year-Mortality
Total Sudden Death
LBBB
No LBBB
Study population
11.9
16.1
10.5
5.5 4.9
7.3
p<0.001
p<0.001
No LBBB
Unadjusted 1
Adjusted 1
RR of Total Death
No LBBB
Unadjusted 1
RR of Sudden Death
Adjusted 1
1.70
(1.34-2.21)
1.36
(1.15-1.61)
LBBB
1.58
(1.21-2.06)
LBBB
1.34
(1.05-1.42)
INCHF
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
26. Witch is the prognostic value
of QRS width ?
• VEST study analysis
• NYHA Class II – IV pz
• 3,654 ECGs digitally scanned
• Age, creatinine, LVEF, heart
rate, and QRS duration
found to be independent
predictors of mortality
• Relative risk of widest QRS
group 5x greater than
narrowest
60%
70%
80%
90%
100%
0 60 120 180 240 300 360
Days in Trial
CumulativeSurvival
QRS
Duration
(msec)
<90
90-120
120-170
170-220
>220
Adapted from Gottipaty et al. JACC
1999; 33(2):145A (abstract 847-4)
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
27. CHF Population
6.5 Mio
NYHA III + IV (30 - 35%)
1.95 Mio
Wide QRS (10 - 30%)
Resynchronization Rx
Target Population:
195’000
650’000
Incidence = 580’000 (9.0%)
Mortality = 300’000 (4.6%)
CHF Population in EuropeCHF Population in Europe
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
28. Frank-Starling Mechanism
a. At rest, no HF
b. HF due to LV
systolic dysfunction
c. Advanced HF
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
29. Pressure-Volume Loop
Varying the PreloadPRESSUREPRESSURE
VOLUMEVOLUME
AA
The Frank-Starling law
reflects that increased
diastolic volume (preload)
results in:
1. More tension development
2. Greater stroke volume
ESV constantESV constant
BB CC
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
31. PRESSUREPRESSURE
VOLUMEVOLUME
ESPVR-2
ESPVR-2
1. Stroke volume increases1. Stroke volume increases
2. End-systolic volume decreases2. End-systolic volume decreases
The slope of this almost linearThe slope of this almost linear
relation responds to changes ofrelation responds to changes of
the cardiac contractile state:the cardiac contractile state:
an increase in contractilityan increase in contractility
increases the slopeincreases the slope
PV Loop Varying the contractility
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
32. Poor Quality of Life
for HF patients Overall perception of health
36
45
55
48
48
52
56
58
70
Heart Failure NYHA Class IV
Heart Failure NYHA Class III
Heart Failure NYHA Class II
Chronic Bronchitis
Valve disease symptomatic
AF symptomatic
Angina
Depression
General population
Adjusted SF 36 means Hobbs FDR, et al. Eur Heart J 2002
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
33. Sinus
node
AV
node
Bundle
branch or
diffuse block
Delayed conduction
• Delayed AV sequence
• Mitral regurgitation
• Decreased filling time
Delayed Ventricular ActivationDelayed Ventricular Activation
What is abnormal in the HF pts?What is abnormal in the HF pts?
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
34. SinusSinus
nodenode
AVAV
nodenode
BundleBundle
branch orbranch or
diffuse blockdiffuse block
Delayed conductionDelayed conduction
• Abnormal RV-LV
sequence
• Abnormal LV activation
sequence
• Segmentary dyskinesia
• Aggravation of mitral
regurgitation
• Disynchrony of RV and
LV filling flows
Ventricular ContractionVentricular Contraction
What is abnormal in the HF pts?What is abnormal in the HF pts?
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
35. Sinus
node
AV
node
Bundle
branch or
diffuse block
Delayed conduction
• Delayed AV sequence
• Mitral regurgitation
• Decreased filling time
Delayed Ventricular ActivationDelayed Ventricular Activation
What is abnormal in RVA pacingWhat is abnormal in RVA pacing
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
36. SinusSinus
nodenode
AVAV
nodenode
BundleBundle
branch orbranch or
diffuse blockdiffuse block
Delayed conductionDelayed conduction
• Abnormal RV-LV
sequence
• Abnormal LV activation
sequence
• Segmentary dyskinesia
• Aggravation of mitral
regurgitation
• Disynchrony of RV and
LV filling flows
Ventricular ContractionVentricular Contraction
What is abnormal in RVA pacingWhat is abnormal in RVA pacing
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
37. • Optimizes AV contraction sequence
• Reduces pre-systolic mitral regurgitation
• Improves atrial preloading of the ventricle
• Increases filling time
Mechanism I:Mechanism I:
Atrio-Ventricular SynchronyAtrio-Ventricular Synchrony
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
What does pacing changeWhat does pacing change??
38. OAVD Restores AV Synchrony
PP RR
INTRINSICINTRINSIC
AorticAortic
pressurepressure
LVLV
pressurepressure
PPPP
PeakPeak
atrial systoleatrial systole
Start ofStart of
LV systoleLV systole
Diastolic
Mitral
Regurgitation
Maximum
Effective Preload
PP VV
PACEDPACED
PPPP
SynchronizedSynchronized
LV and atrialLV and atrial
systolessystoles
Auricchio et al, PACE 1998
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
43. LV Lead Implant
Historical Evolution
• Thoracic epicardial LV lead - 1994 1
• RV lead adapted for transvenous LV implant - 1996 2
• CS lead adapted for transvenous LV implant -1997 3
• Special designed transvenous LV lead - 1998 4
• Guiding catheter sheath for LV lead delivery -1998 5
1. Bakker et al. PACE 1994; 2. Cazeau et al. PACE 1996;
3.Daubert et al. PACE 1997; 4. Gras et al. PACE 1998
5. Lurie et al. Circulation 1998
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
47. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Short term effectsShort term effects
RESULTSRESULTS
•WIDE variability in a board spectrumWIDE variability in a board spectrum
•IMPROVEMENT of Systolic Function IndexIMPROVEMENT of Systolic Function Index
•Similar effects on GLOBAL systolic functionSimilar effects on GLOBAL systolic function
with LV and BV CONFIGURATIONwith LV and BV CONFIGURATION
•BV CONFIGURATION better on regional systolicBV CONFIGURATION better on regional systolic
functional index (PW-DTI)functional index (PW-DTI)
•NO effects on DIASTOLIC functionNO effects on DIASTOLIC function
•Haemodinamic effect related to OAVDHaemodinamic effect related to OAVD
•QRS effects not always related toQRS effects not always related to
Haemodinamic effectHaemodinamic effect
48. InSync Italian Registry
QRS duration (msec) 172+32
Ejection fraction (%) 25+7
LV end Diast. Diameter (mm) 71+9
NYHA functional class 3,15+0,61
6 min walking test (m) 269+142
Chronic Atrial Fibrillation 17,4%
190 patients M= 82,8%; Age= 68+ 8
ETIOLOGY:
Ischemic 46,6%; Idiopatic 37,9%; Other 15,5%
InSync
Italian
Registry
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
49. InSync
Italian
Registry
M. Zardini et al, Eur Hear 2000
LVEF %
0
10
20
30
40
BASELINE FOLLOW-UP
%
6m HWT
0
100
200
300
400
500
BASELINE FOLLOW-UP
m
NYHA class
0
1
2
3
4
BASELINE FOLLOW-UP
QOL Score
0
10
20
30
40
50
60
70
80
BASELINE FOLLOW-UP
p < .0001
p < .0001 p < .0001
p < .0001
Clinical Outcome
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
50. Myocardial Performance Index (MPI)Myocardial Performance Index (MPI)
measurementmeasurement
EE AA EE AA
Mitral flowMitral flow
ICTICT IRTIRTETET
Aortic flowAortic flow
ICT: isovolumetric contraction time
ET: ejection time
IRT: isovolumetric relaxation time
ICT+IRT = MPIICT+IRT = MPI
ETET
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
51. Echocardiographic evaluation ofEchocardiographic evaluation of
the effect of biventricular pacingthe effect of biventricular pacing
MC Porciani et al, Eur Heart J Supplements, Vol. 2 (Suppl J) October 2000
LMPILMPI
RMPIRMPI
Baseline Follow-up p<Baseline Follow-up p<
(vs. baseline)(vs. baseline)
1.2 ± 0.671.2 ± 0.67
1.35 ± 0.761.35 ± 0.76
0.8 ± 0.50.8 ± 0.5
0.81 ± 0.390.81 ± 0.39
0.0090.009
0.040.04
InSync
Italian
Registry
52. Auricchio et al., NASPE ‘99
PATH-CHF:
Inclusion Criteria (42 pts)
• Dilated cardiomyopathy of any etiology
• NYHA Class III (> 6 months) or NYHA IV
• Optimal individual drug therapy
• QRS duration >120 msec
• PR Interval >150 msec
• Sinus rate > 55 bpm
• No conventional pacemaker indication
PATHCHF
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
53. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• First controlled, single blinded, randomized and with cross-
over technique clinical study
1. best unichamber site (haemodinamic effects)
2. Optimal atrio-ventricular delay (OAVD)
3. Long term clinical efficacy
• Three different configuration (A-RVA, A-LV
e A-BVP)
• “Acute” haemodinamic evalutation of best configuration
(unichamber or BVP)
PATH-CHF PATHCHF
54. 4 weeks
4 weeks
One Year
4 weeks
Acute Testing at Implant
Randomization Prior to Discharge
Pre-OP Evaluation
Best Unichamber Biventricular
No Pace No Pace
Biventricular Best Unichamber
Best Chronic Pacing Mode
FlexStim
PATH CHF:
Study Design PATHCHF
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
58. Hospitalization for HF
MeanMean ±± SEMSEM
NN == 1616
0
10
20
30
40
daysofhospitalization
1 Year1 Year
Pre-ImplantPre-Implant
1 Year1 Year
Post-ImplantPost-Implant
PP == .003.003
PATHCHF
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
59. MUSTIC:
Inclusion Criteria (67 pts)
• Dilated cardiomyopathy of any etiology
• NYHA Class III
• Optimal individual drug therapy
• LBBB and QRS duration >150 msec
• LVEF<35% and LVEDD>60mm
• 6-MWT<450m
• SR & no conventional pacemaker indication
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
60. MUSTIC study : Results
Results Active
pacing
Inactive
pacing
p
6-min w (m) 399 ± 100 326 ± 134 .0001
QOL score 29.6 ± 21.3 43.2 ± 22.8 .0002
VO2 (ml/min/Kg) 16.2 ± 4.7 15 ± 4.9 .02
67 pts, mean age 64 yrs, mean LVEF 23%,
mean QRS width 177 ms, NYHA III
S.Cazeau et al NEJM 2001;344:873-80S.Cazeau et al NEJM 2001;344:873-80
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
61. MIRACLE
Inclusion Criteria (571 pts)
• Moderate or severe heart failure
NYHA Class III or NYHA IV
• Stable optimal HF medical therapy regimen for≥1mo
– Diuretic (93-94%)
– ACE-I or ARB (90-93%), if tolerated
– β-blocker (55-62%) - stable regimen for ≥ 3 months
• QRS duration ≥130 msec
• LVEF ≤ 35% or LVEDD ≥ 55mm (echo measure)
• Sinus rate > 55 bpm
• 6 MWT<450m
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Abraham WT, Fisher WG, Smith AL, et al.
N Engl J Med 2002;346:1845-1853
67. Primary Efficacy
Results Summary
• Pre-specified objective exceeded
– P ≤ 0.05 for all three endpoints
• Results not influenced by use of beta blockers, heart failure
etiology, bundle branch block pattern, QRS duration
Control CRT P
Value
Change in 6-minute walk
distance (m)
+ 10 + 39 0.005
Change in Minnesota
LWHFQ Score
- 9 - 18 0.001
Change in NYHA Functional
Class (% improved)
38% 68%
<
0.001
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
68. Paired median change at 6 months
from baseline. Error bars are 95% CI.
Improvement in Peak VOImprovement in Peak VO22
-0.5-0.5
0.00.0
0.50.5
1.01.0
1.51.5
2.02.0
ControlControl
(n=145)(n=145)
CRTCRT
(n=158)(n=158)
ml/kg/minml/kg/min
P=0.009P=0.009
Improvement inImprovement in
Total Exercise TimeTotal Exercise Time
00
3030
6060
9090
120120
ControlControl
(n=146)(n=146)
CRTCRT
(n=159)(n=159)
secondsseconds
P=0.001P=0.001
BaselineBaseline
(ml/kg/min)(ml/kg/min)
13.7 ± 3.8
14.0 ± 3.5
BaselineBaseline
(secondsseconds)
462 ± 217
484 ± 209
CRT Improves Metabolic Exercise
Abraham WT, Fisher WG, Smith AL, et al.
N Engl J Med 2002;346:1845-1853
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
69. Change in MR Jet AreaChange in MR Jet Area
-4-4
-3-3
-2-2
-1-1
00
11
ControlControl
(n=118)(n=118)
CRTCRT
(n=116)(n=116)
cmcm22
P<0.001P<0.001 P=0.009P=0.009
Change in LVEDDChange in LVEDD
-6-6
-4-4
-2-2
00
22
ControlControl
(n=118)(n=118)
CRTCRT
(n=116)(n=116)
mmmm
P<0.001P<0.001
Absolute Change in LVEFAbsolute Change in LVEF
-2-2
00
22
44
66
88
ControlControl
(n=146)(n=146)
CRTCRT
(n=155)(n=155)
%%
Baseline (mm)Baseline (mm)
69 ± 10
70 ± 10
Baseline (cmBaseline (cm 2
)
7.2 ± 4.9
7.6 ± 6.4
Baseline (%)Baseline (%)
22 ± 6
22 ± 6
Paired median change from baseline at 6 months. Error bars are 95% CI.
CRT Cardiac Function and Structure
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
71. Control 225 214 204 197 191 179 70
CRT 228 218 213 209 204 201 99
Patients At RiskPatients At Risk
70%70%
75%75%
80%80%
85%85%
90%90%
95%95%
100%100%
00 11 22 33 44 55 66
Months After RandomizationMonths After Randomization
EventFreeEventFreeSurvivalSurvival(%)(%)
CRTCRT
ControlControl
P = 0.033P = 0.033
Relative risk = 0.60;Relative risk = 0.60;
95% CI (0.37, 0.96)95% CI (0.37, 0.96)
Time to Death or Worsening HF
requiring Hospitalization
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
72. – is SAFE and well tolerated
– improves QOL, NYHA class & exercise capacity (6 MWT)
– improves CARDIAC FUNCTION and STRUCTURE
– improves HF composite response
– may have a favorable effect on combined measures of morbidity
and mortality
In NYHA Class III and IV systolic HF patientsIn NYHA Class III and IV systolic HF patients
with intraventricular conduction delays, CRT:with intraventricular conduction delays, CRT:
conclusions
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
MIRACLE
Abraham WT, Fisher WG, Smith AL, et al.
N Engl J Med 2002;346:1845-1853
First parallele, prospective, double blinded
randomized control trial
73. • In NYHA class III and IV heart failure patients
with ventricular dysynchrony and with or without an
ICD indication, CRT significantly improves quality
of life, NYHA class, and maximal exercise capacity
(peak VO2, exercise time)
• Population differences and timing of baseline
assessment might explain the discordant
6-minute walk results
• CRT adds incremental benefit to the treatment of
heart failure
conclusionsconclusions
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
MIRACLE
75. Conclusions (1)
Severe CHF represent one of the major challenge
for cardiologists during the next decades.
Pharmacological treatment will certainly remain the
baseline procedure but non pharmacological
treatments will certainly become an adjunct.
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
76. Conclusions (2)
The role of pacing has to be determined but the
series published up to now are very encouraging and
the trials results demonstrate that this procedure
does not increase mortality it might become the
leader of the non pharmacological procedure for a
selected number of patients.
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
77. Risk of Sudden Death:Risk of Sudden Death:
GISSI-2 TrialGISSI-2 Trial
Patients without
LV Dysfunction
(LVEF >35%)
Maggioni AP. Circulation. 1993;87:312-322.
Patients with
LV Dysfunction
(LVEF < 35%)
No PVBs
1-10 PVBs/h
> 10 PVBs/h
0.86
A
0.88
0.90
0.92
0.94
0.96
0.98
1.00
0 30 60 90 120 150 180
Days
Survival
p log-rank 0.002
0.88
0.90
0.92
0.94
0.96
0.98
1.00
0 30 60 90 120 150 180
Days
Survival B
p log-rank 0.0001
0.86
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
78. Challenges in electrical management of HF
Ventricular Arrhythmias/SCD: the
majority of deaths in Heart Failure are due to SD
NYHA II
Other
24%
CHF
12%
Sudden
death
64%
N=103
NYHA III
Sudden
death
59%
CHF
26%
Other
15%
N=232
NYHA IV
Sudden
death
33%
CHF
56%
Other
11%
N=27
N = number of deaths
MERIT-HF study
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
79. NYHA Class III/IV HF*,NYHA Class III/IV HF*,
EFEF ≤≤ 35%, QRS35%, QRS ≥≥ 130 ms,130 ms,
Stable HF Medical TherapyStable HF Medical Therapy
No indicationNo indication
for ICDfor ICD
IndicationIndication
for ICDfor ICD
MIRACLEMIRACLE
(InSync)(InSync)
MIRACLE ICDMIRACLE ICD
(InSync ICD)(InSync ICD)
* Separate protocol for MIRACLE ICD Class II* Separate protocol for MIRACLE ICD Class II
Inclusion
Criteria
MIRACLE and MIRACLE ICD Trials
W.T. Abraham for MIRACLE and MIRACLE ICD Investigators
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
80. BaselineBaseline
ImplantImplant
AttemptAttempt
SuccessfulSuccessful
ImplantImplant
ControlControl CRTCRT
Pre-dischargePre-discharge
RandomizationRandomization
1, 3, 61, 3, 6
MonthMonth
Follow-upFollow-up
1, 3, 61, 3, 6
MonthMonth
Follow-upFollow-up
CRTCRT
DoubleDouble
BlindedBlinded
StableStable
MedicalMedical
TherapyTherapy
≤≤ 11
weekweek
CRTCRT
Long term follow upLong term follow up
every 6 monthsevery 6 months
• 369 randomized patients369 randomized patients
• 182 CONTROL and 187 CRT182 CONTROL and 187 CRT
• Control: No pacingControl: No pacing
• Treatment (CRT): atrial synched pacingTreatment (CRT): atrial synched pacing
• OMT for HF stability maintainedOMT for HF stability maintained
• ICD active in all patients of MIRACLE ICDICD active in all patients of MIRACLE ICD
MIRACLE ICD study design
W.T. Abraham for MIRACLE and MIRACLE ICD Investigators
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
182182 187187
369369
81. Quality of Life
30
35
40
45
50
55
60
Baseline Six Months
Score
Control n=346
CRT n=375
Treatment Effect, P < 0.001Treatment Effect, P < 0.001
ImprovementImprovement
W.T. Abraham for MIRACLE and MIRACLE ICD Investigators
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
82. NYHA Functional Class
Baseline versus 6 Months
4% 2% 4% 3%
59%
30%
46%
32%
32%
52%
38%
48%
6%
16% 12% 16%
0%
20%
40%
60%
80%
100%
MIRACLE
Control
(n=196)
MIRACLE
CRT
(n=211)
MIRACLE
ICD Con
(n=158)
MIRACLE
ICD CRT
(n=165)
Improved 2 or more
Improved 1 class
No Change
Worsening class
Treatment Effect, P < 0.001Treatment Effect, P < 0.001
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
83. Peak VO2
12
13
14
15
16
Baseline* Six Months
ml/kg/min
Control n=263
CRT n=276
Treatment Effect, P = 0.009Treatment Effect, P = 0.009
**
MIRACLE, pre-implant; MIRACLE ICD, post-implantMIRACLE, pre-implant; MIRACLE ICD, post-implant
W.T. Abraham for MIRACLE and MIRACLE ICD Investigators
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
84. Cardiopulmonary Exercise Time
450
475
500
525
550
575
600
Baseline* Six Months
seconds
Control n=265
CRT n=277
**
MIRACLEMIRACLE, pre-implant;, pre-implant; MIRACLE ICDMIRACLE ICD, post-implant, post-implant
Study Effect, P < 0.001Study Effect, P < 0.001Treatment Effect, P < 0.001;Treatment Effect, P < 0.001;
W.T. Abraham for MIRACLE and MIRACLE ICD Investigators
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
85. 6 Minute Walk Distance
240
260
280
300
320
340
360
Baseline Six Months
DistanceWalked(m)
MIRACLE Control
N=196
MIRACLE CRT
N=211
MIRACLE ICD
Control N=158
MIRACLE ICD
CRT N=165
Treatment Effect, P = 0.09; Study Effect, P < 0.001Treatment Effect, P = 0.09; Study Effect, P < 0.001
W.T. Abraham for MIRACLE and MIRACLE ICD Investigators
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
86. MIRACLE ICD
6 MWT (6 Months vs. 1 Month)
300
310
320
330
340
350
360
One Month Six Months
DistanceWalked(m)
MIRACLE ICD
Control N=143
MIRACLE ICD
CRT N=151
Treatment Effect, P = 0.07Treatment Effect, P = 0.07
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
W.T. Abraham for MIRACLE and MIRACLE ICD Investigators
87. Survival
80%
85%
90%
95%
100%
0 1 2 3 4 5 6
Months Since Randomization
%ofPatientsSurviving
Control n=402 CRT n=415
P=0.42
W.T. Abraham for MIRACLE and MIRACLE ICD Investigators
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
88. CRT Effect on LV Structure at
6 Months in Moderate to Severe
HF
-40
-20
0
P<0.001
P=0.06
LVEDV
Avg. Change
(mL)
-6
-4
-2
0
2
MIRACLE MIRACLE ICD Contak CD
P<0.05 P=0.81 P=0.001
Data sources: MIRACLE: Circulation 2003
MIRACLE ICD:JAMA 2003
Contak CD: J Am Coll Cardiol 2003
Control CRT
LVEDD
Avg. Change
(mm)
NOT
REPORTED
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
89. CRT Improves Cardiac Function
at 6 Mo in Moderate to Severe HF
0
2
4
6
P<0.001
P=0.12
P=0.029
LVEF
Avg. Change
(Absolute %)
-3
-2
-1
0
MIRACLE MIRACLE ICD Contak CD
P<0.001
P=0.58
Data sources: MIRACLE: Circulation 2003
MIRACLE ICD:JAMA 2003
Contak CD: J Am Coll Cardiol 2003 Control CRT
MR Jet Area
Avg. Change
(cm2)
Not
Reported
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
90. CRT Improves QOL & Functional
Capacity in Moderate to Severe HF
-20
-15
-10
-5
0
P<0.001 P=0.02 P=0.017P<0.001
QoL Score
(MLWHF)
Avg. Change
0%
20%
40%
60%
80%
MIRACLE MUSTIC SR MIRACLE ICD Contak CD
P<0.001 P=0.006P=0.007
Data sources:
MIRACLE: Circulation 2003;107:1985-90 MUSTIC SR: NEJM 2001;344:873-80
MIRACLE ICD:JAMA 2003;289:2685-94 Contak CD: JACC 2003;2003;42:1454-59
Control CRT
NYHA Class
Proportion
Changing 1
or more
Classes
Improve. ↓
Not
Reported
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
91. CRT improves Exercise Capacity
in Moderate to
Severe HF
-20
0
20
40
60 P<0.001 P=0.36 P=0.029
P<0.001
6 Min Walk
Avg. Change
(m)
00
0
1
2
3
MIRACLE MUSTIC SR MIRACLE ICD Contak CD
P<0.001
P=0.029
P=0.04
P=0.003
Data sources:
MIRACLE: Circulation 2003;107:1985-90 MUSTIC SR: NEJM 2001;344:873-80
MIRACLE ICD:JAMA 2003;289:2685-94 Contak CD: JACC 2003;2003;42:1454-59
Control CRT
Peak VO2
Avg. Change
(mL/kg/min)
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
92. Benefits Sustained Through 2 yr:
MIRACLE Study Program
0
100
200
300
400
500
Mean
distance
walked in
6 minutes
(m)
1
2
3
4
0
20
40
60
80
100
6 (N=1124) 12 (N=693) 18 (N=320) 24 (N=68)
Months of Active CRT
Mean NYHA
Functional Class
Mean QoL Score
Improvement ↓
Baseline
Follow-up
Paired
Data
Displayed
P<0.001 P<0.001 P<0.001 P=0.01
P<0.001 P<0.001 P<0.001 P<0.001
P<0.001 P<0.001 P<0.001 P<0.001
Source: Abraham,
WT et al. AHA 2003
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
93. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
CRT Procedure and Device Related Risks
Com plicat ions ( 1)
4,8
3,7
1,5
1,0
1,8
0,3
10,6
10,0
2,3
2,4
1,7
0,3
0 5 10 15
Unsucess. Implant
LV Lead
Coronary Sinus
Infection
30 day mortality
Procedure death
Percent of Pat ient s
MIRACLE+CONTAK
CD+MIRACLE ICD
InSync III/Attain
4193
Reduced Procedure Time w it h
I ncreased Experience (2)
60
120
180
240
300
Up t o first
5
Next 6 t o
10
Next 11
more
Cent er-based experience
ImplantTime(minutes)
P < 0.001
Study Period Attempts
Primary
LV Lead
MIRACLE 11/98 – 12/00 591 Attain 2187
Contak CD 2/98 – 12/00 517 EasyTrak
MIRACLE ICD 10/99 – 8/01 636 Attain 4189
InSync III 11/00 – 6/02 334 Attain 4193
1. Greenberg, et al.
PACE 2003;26(4p2):
952 (Abstract 93)
2. Unpublished data.
Medtronic. Inc.
94. Improved Cardiac Function
without Oxidative Stress
0,14
0,16
0,18
0,20
0,22
0,24
500 600 700 800 900
dP/ dtmax (mm/ Hg/ s)
MVO2/HR(RelativeUnits)
Dobutamin
LV Pacing
P< 0.05
Nelson et al. Circulation 2000
Myocardial Oxidative
Metabolism
0
0,02
0,04
0,06
LV RV
kmono(min-1
)
p=
0.86
p=
0.62
n=8
Myocardial Efficiency
Work Metabolic Index
0
2
4
6
8
10
12
mmHG·L·m-2
Baseline CRT
p =0.024
Ukkonen et al. Circulation 2003
n=7
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
95. CRT Does Not Promote
Ventricular Arrhythmias
• Analyzed 1,044 patients
with ICDs from 2 trials:
– CONTAK CD
– MIRACLE ICD
• Odds ratio (CI):
0.92 (0.67 – 1.27)
Patients with VT or
VF during Follow-up
17,2%
18,4%
No CRT CRT
Proportion
Bradley DJ, et al. JAMA 2003
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
96. Study PopulationStudy Population
∀ ≥ 18 years of age
• NYHA Functional Class II
• QRS duration ≥ 130 msec
• LVEF ≤ 35%
• LVEDD ≥ 55 millimeters (echo measure)
• Stable optimal HF medical regimen for ≥ 1 mo.
• Indication for an ICD
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
MIRACLE ICD II
98. InclusionInclusion
CriteriaCriteria MIRACLE ICD II
MIRACLE ICD
JAMA 2003;289:2685
NYHA Functional Class II III/IV
Primary Endpoint Peak VO2 QoL, NYHA, 6 MW
QRS Duration ≥ 130 msec ≥ 130 msec
LVEF ≤ 35% ≤ 35%
LVEDD ≥ 55 mm ≥ 55 mm
Stable, optimal HF medical
regimen
Yes Yes
Indication for an ICD Yes Yes
Device studied InSync ICD (MDT) InSync ICD (MDT)
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
MIRACLE ICD II
99. Study DesignStudy Design
Baseline
ex CPX
Implant
Attempt
Successful
Implant
Control
ICD
CRT
CRT + ICD
Pre-discharge
Randomization
6 Month
Follow-up
6 Month
Follow-up
CRT
Double
Blinded
Stable
Medical
Therapy
≤ 1
week
• Intent to treat analyses
• Comparison between groups
• Core labs: metabolic exercise,
echocardiography, and
neurohormone data
CRT
Long term follow up
every 6 months
CPX
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
100. Enrollment and FUEnrollment and FU
210 Class II 429 Class III/IV
98 Completed 6M FU 82 Completed 6M FU
2 Death 2
1 Missed 6M FU 1
101 Control (ICD+OPT) 85 CRT (CRT+ICD+OPT)
639 Enrolled and Implant Attempted
19 Unsuccessful 191 (91%) Successful
186 Randomized
5 not randomized
- 1 death
- 4 LV lead dislodge.
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
101. VE/VCO2 Ratio
30
35
40
45
Base 6 Mo
P=0.01
Exercise Duration and VE/VCOExercise Duration and VE/VCO22
Cardiopulmonay Exercise
Duration
600
660
720
780
s
Base 6 Mo
P=0.56
• Control (n=79) ♦ CRT (n=66)
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
MIRACLE ICD II
102. Quality of Life Score
(MLWHF)
10
20
30
40
50
Base 6 Mo
P=0.49
6 Minute Walk,QoL, NYHA
Distance Walked in 6
Minutes
300
350
400
450
m
Base 6 Mo
P=0.59
• Control (n=96) ♦ CRT (n=81)
NYHA Class at 6 Months
0%
10%
20%
30%
40%
50%
60%
70%
I II III IV
ProportionofPatients
P=0.05
Control (n=98)
CRT (n=82)
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
MIRACLE ICD II
103. Left Ventricular End
Systolic Diameter
200
250
300
350
400
cm3
Base 6 Mo
P=0.01
CRT Promotes Reverse
Remodeling in Class II CHF
Left Ventricular End
Diastolic Diameter
200
250
300
350
400
cm3
Base 6 Mo
P=0.04
Left Ventricular
Ejection Fraction
20
22
24
26
28
30
%
Base 6 Mo
P=0.02
• Control (n=85) ♦ CRT (n=69)
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
MIRACLE ICD II
104. CRT on Composite Response
36% 34%
31%
58%
22% 20%
0%
20%
40%
60%
Improved No Change Worsened
Proportion
Control (n=101) CRT (n=85) Chi-square test
P = 0.01
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
MIRACLE ICD II
105. CRT Effect on
Ventricular
Arrhythmias
• 25/101 pts assigned to CTR
89 VT or VF events
• 18/85 pts assigned to CRT
61 VT/VF events
25%
21%
0%
5%
10%
15%
20%
25%
Control CRT
p = 0.61
During 6 Month
Randomization Period
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
MIRACLE ICD II
106. Conclusions
– Does not alter exercise performance or QOL
– Improves measures of CHF disease progression
• improves cardiac function and structure
• improves heart failure composite response
– Neither promotes nor inhibits ventricular arrhythmias
In patients with mild systolic HF (NYHA class II) a
wide QRS complex, and an indication for an ICD, CRT:
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
MIRACLE ICD II
108. Cumulative Enrollment in C.R.Cumulative Enrollment in C.R.
Randomized TrialsRandomized Trials
0
1000
2000
3000
4000
1999 2001 2003 2005
Results Presented
CumulativePatients
PATH CHF
MUSTIC SR
MUSTIC AF
MIRACLE
CONTAK CD
MIRACLE ICD
PATH CHF II
COMPANION
MIRACLE ICD II
CARE HF
•• Actual ProjectedActual ProjectedDOUG SMITHDOUG SMITH
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
109. • Difficult cannulation of coronary sinus
• Anatomical abnormalities of coronary venous tree
• High thresholds
• Phrenic stimulation
Biventricular PacingBiventricular Pacing
Success rate is conditioned by:
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
110. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
1. Improvemente of Clinical and haemodinamic index
(NYHA, LVEF, 6-MWT, V02, QOL).
2. Approved by FDA (class II) for CHF, NYHA III-
IV, refrattari a OMT, intra-ventricular
contraction delay and IVCD
3. OMOGENEIZZAZIONE tempi di attivazione VSx
4. Reverse remodelling
5. Reduction of mortality (combined with ICD)
6. No effects on metabolic index (Dp/Dt)
Long term effects:Long term effects: RESULTSRESULTS
111. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
6. Effetti legati a modifiche del RCIV (TARGET),
poi IVCD ed infine OAVD (anche in pz FA)
7. Efficacia INDIPENDENTE dall’etiologia
8. Best response in pts isposta maggiore in classe
NYHA III ma anche in classe NYHA II (poco
studiata) e IV (casi più gravi)
9. ASSENZA di EFFETTI ARITMOGENI
(probabile riduzione effetti pro-aritmici)
10.Riduzione atività ADRENERGICA
11. Riduzione MORTALITA’
EFFETTI CRT A LUNGO TERMINE
112. Reduced Mortality
in Heart Failure
ACE-I & Beta Blockade
Reduce Mortality
11,5%
15,6%
12,4%
7,8%
0%
4%
8%
12%
16%
SOLVD-T MERIT-HF
+ CIBIS II
1YearMortality
Placebo Treatment
Further Reduction
with CRT + ICD
for Higher Risk Patients
HF
Mortality
Sudden
Cardiac
Death
CRT
ICD
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
113. Mortality/Morbidity From Published
Randomized, Controlled Trials
Risk reduction with CRT
Study
(n random.) FU
Mor-
tality &
Hosp.
Mortal.
& HF
Hosp.
Mor-
tality
HF
Mort.
HF
Hosp.
MIRACLE1
(n=453)
6 Mo NR 39%* 27% NR 50%*
MIRACLE ICD2
(n=369)
6 Mo 2% 0% 0% NR NR
Contak CD3
(n=490)
3-6 Mo NR NR 30% NR 18%
Meta-analysis4
(n=1634)
3-6 Mo NR NR 23% 51%* 29%*
* P < 0.051. Abraham WT, et al. N Engl J Med 2002
2. Young JB, et al. JAMA 2003
3. Higgins SL, et al. JACC 2003
4. Bradley DJ, et al. JAMA 2003
[Inc. MIRACLE, M.ICD, Contak CD, and MUSTIC]
NR = Not reported in publication
Individual trials were not powered
for mortality or hospitalization
114. Weight of Evidence: CRT
• More than 4000 patients evaluated in
randomized controlled trials
• Consistent improvement in QOL, functional
status, and exercise capacity
• Strong evidence for reverse remodeling
– ↓ LV volumes and dimensions
↑ LV ejection fraction
– ↓ Mitral regurgitation
Courtesy of Dr. Bill Abraham
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
115. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• CRT in NYHA class II ?
• Which implication in pts with
unstable Haemodinamic profile ?
• CRT in chronic Atrial Fibrillation ?
• CRT in Right Bundle Branch Block ?
• QRS<120ms or QTc dispersion ?
• CRT as “Up-grading” in RVA pacing ?
Actual Key QuestionsActual Key Questions
116. Creating Realistic
patients expectations
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• Approximately two-third of patients should experience
improvement (responders vs. non-responders)1
• Some patients may not experience immediate improvement
117. • Have patients set their own goals of what they
would like to do following CRT:
Grocery shopping, Decreasing Lasix dose
Walking to the mailbox without stopping,
Lying flat to sleep
• Encourage them to be part of the group that
responds to their therapy
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Creating Realistic expectations
118. Current treatment of CHF
Functional improvement
Mortality reduction
– pump failure
– sudden death
DrugsDrugs
LV/LV/BiVBiV PacingPacing ?
ICDICD
DrugsDrugs
LV/LV/BiVBiV
ICD ?ICD ?
≈ 15% of all conventional ICD could be eligible for BVP
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
119. Summary
• Large number of patients studied in CRT
• Concordant proof that CRT improves QOL,
Exercise Capacity, Functional Capacity
(Improvements persist through 1 year)
• CRT reduces the risk of mortality and HF due to
worsening HF
• CRT + ICD reduces risk of mortality
• CRT improves cardiac function and structure
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
120. Relative Cost of CRT
Cost per patient
$0$20$40$60
CRT+ I CD
CRT
Hip/ knee replace
PTCA
CABG
Dialysis
$ t housands
Total Annual Expenditures
$0 $5 $10 $15 $20
$ Billions
Doug Smith:
Doug Smith:
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
121. 0
5000
10000
15000
Baseline Post-implant
Intensive care
Cardiology
Others
Patient Cost Baseline: 12,784 Euro
Patient Cost (Implant included): 12,362 Euro
Patient Cost Post-implant: 1,680 Euro
Hospital costs per patient
Cost Effectiveness
Analysis of Biventricular
Pacing in HF
Curnis A 2001
Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
129. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• Percentage of potential RESPONDER
• Prognostic value of diagnostic index?
• Results of TRIAL
• UNIVARIATE/MULTIVARIATE
130. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• PERCENTUALE reale di “responder”
(25-30% di “non responder”)
• Grado di ACCURATEZZA degli indici predittivi
• MORBIDITA’ asociata
(BPCO, IRC, CHF, Ipert. Polmonare)
• Grado di ASSOCIAZIONE tra ASINERGIE e BBSx
• Popolazione “target” CRT?
• Severe CHF (NYHA IV) or haemodinamic instability
(mortalità 70% a 12M inotropi ev)
131. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• ASSOCIAZIONE QRS>120ms / dissinergie
• Pz CMD/HF con BBSx risposta emodinamica più
scadente
• 15% pop. CMD/HF con QRS>120ms
• 1/3 pop. CMD/HF con CHF sistolica presenta
QRS>120ms
• 30% pop. CMD/HF in classe NYHA III-IV
QRS>120ms
• 60% pz. CMD/HF alterazioni PQ
Witch is the prognostic value
of QRS width ?
132. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• Elevata correlazione tra QRS e IVCD
• Bassa correlazione tra QRS e RCIV (marker CRT)
• QRS parametro specifico ma poco sensibile
• Associazione CMD/HF, BBSx ed eventi avversi a
distanza (fattore prognostico negativo)
133. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• Fenomeni di ASINERGIA secondari ad attivazione
asincrona tra i segmenti miocardici (SIV/PP)
• Attivazione SIV quando il restante miocardio è in
“compliance” ed attivazione parete L e PL tardiva
e connessa a RM tele-diastolico
• Creazione di un GRADIENTE ANOMALO VSx/VDx,
con progressivo incremento LVEDD e riduzione
LVEF
regionale, SV/CO, PA media, Dp/Dt• I fenomeni meccanici VSx alterati per ritardati
movimenti apertura/chiusura AoV e chiusura di MV
• Mancata OMOGENEIZZAZIONE tempi di recupero
134. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• Spostamento del punto di equilibrio ad un livello
ancora più critico nei pz CMD/HF
• Se PQ lungo, AVD critico e responsabile di un
incompleto movimento di chiusura MV (mancanza
consecutio onda A/PEP)
• Il criterio ECHO (53%) è maggiormente
predittivo di ASINERGIA rispetto al criterio
ECG (30%) nei pz CHF classe NYHA III-IV
135. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
I risultati di uno studio retrospettivo (241 pz CHF)
considerano i parametri ECG (BBSx e QTc) nei CHF
i migliori indici predittivi negativi all’analisi
univariata, mentre i parametri ECHO ed emodinamici
i migliori indici predittivi di mortalità (RCIV, VO2
peak, VO2 al raggiungimento della soglia anaerobica,
LVEF) al’analisi multivariata (Shanim)
136. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
INSYNC (150 centri/5.517 pz)
Registro osservazionale (CHF, BBSx e QRS≥140ms)
associazione ad un incremento mortalità per ogni
causa e ad un incremento frequenza di mortalità per
SCD all’analisi univariata. Rischio relativo di
mortalità persisteva dopo aggiustamento dei dati
(età, patologia cardiaca, altri indicatori di severità
HF, prescrizione ACE-I/β-bl.) all’analisi multivariata
VEST (3654 ECG pz. CHF NYHA II-IV)
Tra i parametri predittivi indipendenti di mortalità
c’era la durata del QRS
(QRS≥200ms RR>5 volte rispetto a QRS≤90ms)
137. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
CONCLUSIONI INSYNC/VEST:
ECG basale potente MARKER prognostico nei CHF
INSYNC e VEST
relazione tra BBSx ed indici di sopravvivenza
PRESUPPOSTO di PARTENZA: maggiore QRS,
maggiore sarà il grado di asincronia VSx e quindi
maggiori saranno i benefici della CRT.
138. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Kass (Circulation '99) Blanc (Circulation '97)
Risultati in “ACUTO““ACUTO“ lavori iniziali evidenza di
correlazione significativa tra QRS e CRT
(valutazione EMODINAMICAEMODINAMICA)
Risultati CRT in 22 pz CHF con micromanometro a
doppio sensore (LVSP e AoSP) che se
l’ASINERGIA rappresenta la chiave predittiva di
efficacia, la combinazione QRS≥155ms e Dp/Dt
basale≤700mmHg/s eccellente combinazione
Nelson
139. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
NONNON è un dispositivo di assistenza meccanica
NONNON non rappresenta il trapianto cardiaco
NONNON non agisce sul Dp/Dt
Recupero funzionale di aree asinergiche con CRT
Se contrattilità particolarmente depressa
risultati meno brillanti fino a diventare nulli
140. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
ANALISIANALISI
TERMODINAMICATERMODINAMICA
le zone con ATTIVAZIONE PRECOCEATTIVAZIONE PRECOCE si
contraggono contro un carico di lavoro MINIMOMINIMO
(restante miocardio in fase di “compliance”)
e quindi l’accorciamento rapido iniziale non può
tradursi in un aumento della PRESSIONEPRESSIONE Ao
Creazione di un LAVORO NEGATIVOLAVORO NEGATIVO
(E pot. che non si trasforma in E. cinetica).
141. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Le zone che si attivano TARDIVAMENTETARDIVAMENTE
vengono sottoposte ad un carico lavoro ECCESSIVOECCESSIVO
e quindi ad uno elevato STRESS PARIETALE.STRESS PARIETALE.
La loro fase di contrazione trova le regioni già
attivate in ”COMPLIANCE””COMPLIANCE” esercitando un effetto
di stiramento.
ANALISIANALISI
TERMODINAMICATERMODINAMICA
142. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Lavoro miocardico speso per TRASFERIRETRASFERIRE una
certa quantità di E. CINETICAE. CINETICA da una porzione
all’altra della camera cardiaca piuttosto che in Ao
La contrazione delle porzioni attivate
TARDIVAMENTETARDIVAMENTE può avvenire a valvole semilunari
chiuse e/o a valvole AV aperte
ANALISIANALISI
TERMODINAMICATERMODINAMICA
143. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
1.1.AUMENTOAUMENTO del rapporto LVESV/LVEDV
2.2.SPOSTAMENTOSPOSTAMENTO a DESTRA della curva P/V
3.3.ALLUNGAMENTOALLUNGAMENTO PEP>140ms (Q/inizio VTI
Ao)
4.4.ACCORCIAMENTOACCORCIAMENTO del rapporto tra
Ejection Time/Relaxation Time
5.5.RIDUZIONERIDUZIONE LVEF
LAVORO NEGATIVOLAVORO NEGATIVO
ANALISIANALISI
EMODINAMICAEMODINAMICA
144. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
1.1.ALLUNGAMENTOALLUNGAMENTO IVRT e IVRT
2.2.PROLUNGAMENTOPROLUNGAMENTO temporale del MR
3.3.PEGGIORAMENTOPEGGIORAMENTO del grado di MR
4.4.DELAYDELAY temporale tra eventi P/S
(Q-VTI polmonare e Q-VTI aortico >40ms)
5.CONTRAZIONI SEGMENTARIE5.CONTRAZIONI SEGMENTARIE
post-sistoliche VSx (M-mode e DTI).
C’è meno tempo per riempire e svuotare il VSx.
LAVORO NEGATIVOLAVORO NEGATIVO
ANALISIANALISI
EMODINAMICAEMODINAMICA
145. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
(Xiao)
CORRELAZIONE durata QRS e ASINERGIA
meccanica mediante analisi del Dp/Dt Doppler dal MR
Correlazione POSITIVA durata QRS e
(1) durata M.R. (2) IVCT e (3) IVRT.
Correlazione NEGATIVA tra durata QRS e
(1) (+Dp/Dt), (2) intervalli Q-pressione di picco, (3)
intervalli Q-Dp/Dt di picco, (4) Tempo di
riempimento ventricolare (critico se ≤200ms).
ANALISIANALISI
ECOCARDIOGRAFICAECOCARDIOGRAFICA
146. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
ASINERGIAASINERGIA meccanica VSx/VDx
(QRS-VTI AoV (–) QRS-VTI PV)
I PARAMETRO di ASINERGIAI PARAMETRO di ASINERGIA
IVCDIVCD
Elevata CORRELAZIONECORRELAZIONE IVCD / QRS
PREVALENZAPREVALENZA ECG dal 25 al 55%
ASINERGIAASINERGIA presente nel BBSx e nel PM/RVA
INVERSIONEINVERSIONE eventi meccanici VSx/VDx ≈ 10-30ms
CONTRAZIONE RITARDATACONTRAZIONE RITARDATA VSx (≈ 85ms)
PREVALENZAPREVALENZA ECHO fino al 71%
147. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
FASE SISTOLICAFASE SISTOLICA
Prolungamento degli intervalli ELETTROMECCANICI
(Q/VTI AoV, Q/fine VTI AoV, Q/onda E)
FASE DIASTOLICAFASE DIASTOLICA
Prolungamento IVRT e IVCT
Riduzione del riempimento VSx (VTI MV)
Aumento del rapporto VTI-TV/VTI-MV
I PARAMETRO di ASINERGIAI PARAMETRO di ASINERGIA
IVCDIVCD
148. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
IVCD REGIONALEIVCD REGIONALE
(1) Q wave/S-wave DTI
(lateral wall MV anulus and tricuspidalic)
(2) Prolonged MR (non ritardato)
(prolungamento IVRT e IVCT)
(3) Riduzione del tempo di riempimento VSx
(VTI mitralico)
IVCD GLOBALEIVCD GLOBALE
(1) Q wave/inizio flusso aortico
(2) Q wave/inizio flusso polmonare;
I PARAMETRO di ASINERGIAI PARAMETRO di ASINERGIA
IVCDIVCD
149. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Definizione ECHO: contrazione prolungata PP VSx
protratta dopo l’apertura di MV.
CHF QRS>120ms (36%-73%)
CHF QRS<120ms (26%-51%).
DTI (analisi velocità regionali) e sistemi basati su
registrazione digitale di “loop” DTI, (“Tissue
Tracking”, dato quantitativo dell’ampiezza del
movimento longitudinale di ogni segmento miocardico
analizzato durante la sistole) e lo “Strain Rate”
(discriminazione tra movimenti attivi e passivi)
II PARAMETRO di ASINERGIAII PARAMETRO di ASINERGIA
RCIVRCIV
150. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Altissimo VALORE PREDITTIVO per CRT.
Breithard (JACC ’02), Sogaad (JACC '02) e Pitzalis
(JACC '02) con metodica ECHO e valutazioni DTI,
“Strain”, “Strain Rate”, “Color Kinesis” ed “Acoustic
Quantification”.
Marker di ASINERGIA
EFFICACE anche in assenza di altri parametri
(nessun risultato se manca RCIV anche se QRS>120ms)
II PARAMETRO di ASINERGIAII PARAMETRO di ASINERGIA
RCIVRCIV
151. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Elevata CORRELAZIONE con:
(1) LVEF
(2) LVESV
(3) LVEDV.
(4) Dp/Dt massimo
(5) IM moderato-severo
(6) RIDUZIONE durata eventi sistolici e diastolici
effettivi
(7) RITARDATI eventi sistolici e diastolici.
Valutazione DTI PP VSx. (regione “target”)
II PARAMETRO di ASINERGIAII PARAMETRO di ASINERGIA
RCIVRCIV
152. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
AVD nei pazienti con PR lungo
(1) Prolungamento dell’IVCT
(2) Riduzione del riempimento diastolico effettivo
(3) Incremento R.M. tele-diastolico
(già presente nel RCIV) e ulteriore riduzione SV/COOAVD nei pazienti CMD/HF
(1) CORREZIONE FC inappropriatamente basse
(2) CORREZIONE AVD patologici (incremento SV/CO)
(3) Prima del BVP, CRT era AVD breve e RVSTIM
doppio sito (RVA ed RVOT).
III PARAMETRO di ASINERGIAIII PARAMETRO di ASINERGIA
AVDAVD
153. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• MIGLIORAMENTO indici emodinamici (LVEF/NYHA)
in piccola “COORTE” di 16 pazienti CMD/HF con PM-
DDD/AVD breve (report ’90)
• Dato risultato non riproducibile in studi successivi.
• POCHI studi “in acuto” su RVA/RVOT
• SINGOLO studio con “TREND” a favore di RVOT
(non variazioni SV/CO)
• MANCANZA di seguito per dati NON UNIVOCI a
favore
III PARAMETRO di ASINERGIAIII PARAMETRO di ASINERGIA
AVDAVD
154. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
AVD espressione della FASE DIASTOLICA
(nel BAV inadeguato CRONOTROPISMO)
AVD evento finale di una serie di fenomeni legati ad
PERFORMANCE legata ad una normale sequenza di
attivazione AV (onda A deve precedere PEP)
Accoppiamento CRITICO dei due fenomeni
(“TIMING” VTI onda A e PEP)
SVILUPPO di adeguato aumento del gradiente di
pressione AV in fase di PEP, evento temporale che
deve precedere la giustapposizione dei lembi mitralici
e quindi la fase di contrazione ventricolare effettiva.
III PARAMETRO di ASINERGIAIII PARAMETRO di ASINERGIA
AVDAVD
155. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
CONTRAZIONE ATRIALE PREMATURA
(perdita contributo atriale al riempimento)
2. MANCANZA “consecutio” onda A/PEP
3. INCOMPLETA CHIUSURA MV
4. IM TELE-DIASTOLICA
(PTDVS > PAS)
5. “TIMING” onda E successiva RITARDATO
(progressiva fusione onde E/A per AVD prolungati)
6. RIDUZIONE tempo di riempimento VSx GLOBALE
(inizio onda E/fine onda A o VTI mitralico).
III PARAMETRO di ASINERGIAIII PARAMETRO di ASINERGIA
AVDAVD
156. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Analisi ECHO guidata
OAVD specifico per ogni paziente (Karloff, Auricchio)
EFFETTI POSITIVI presenti in un ampio SPETTRO.
EFFETTI DETRIMENTALI con AVD fuori RANGE
(PR<80ms contrazione simultanea ASx/VSx a valvole AV
chiuse, con aumento della pressione in ASx e
reflusso di sangue nelle VP (riduzione SV/CO).
IDENTIFICAZIONE AVD “TARGET” 150ms
nel BAV CONGENITO (Karloff)
III PARAMETRO di ASINERGIAIII PARAMETRO di ASINERGIA
AVDAVD
157. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• TEMPO elettro-meccanico in grado di procurare il
MAGGIORE riempimento DIASTOLICO senza
interferenze con la fase SISTOLICA
• REALE interferenza AVD su SV/CO nel 60%
(AMPIA finestra terapeutica di programmazione)
• OAVD quel ritardo AV in grado di generare il
massimo VTI (Sawhney)
OAVD
III PARAMETRO di ASINERGIAIII PARAMETRO di ASINERGIA
AVDAVD
158. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Numerose PUBBLICAZIONI esprimono il concetto
che una OPTIMAL-CRT necessita di un OAVD.
(Brecker e Gibson) report (’96)
Nesso CAUSALE OAVD/BVP nei pz. CRT/HF, PR
lungo, QRS largo e M.R. (A-BVP con AVD breve nei
pazienti con PR lungo e MR associata)
III PARAMETRO di ASINERGIAIII PARAMETRO di ASINERGIA
AVDAVD
159. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Miglioramento INDICI EMODINAMICI
(riduzione ASINERGIE REGIONALI e GLOBALI)
Miglioramento SINTOMI
Miglioramento QOL (Minnesota HF test score)
Miglioramento TOLLERANZA allo SFORZO (6-MWT)
Miglioramento classe FUNZIONALE (NYHA)
EFFETTI A-BVP
160. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Azione OAVD
(1) TCIV
(2) IVCD
(3) tempo di conduzione AV
(4) tempo di conduzione intra-atriale ed inter-
atriale
(5) FC
(6) stato adrenergico del paziente.
161. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
1. In ogni paziente una OTTIMIZAZIONEOTTIMIZAZIONE della
FUNZIONE SISTOLICA VSx inizia con la
programmazione di un OAVD (Auricchio).
2. Concetto di OAVD connesso a quello di RIAG
(P>100ms), nel quale si verificano differenti tempi
di attivazione AV per il ciclo cardiaco destro e
per quello sinistro.
3. RIAG sottraendo al RIAS (“timing” onda P/inizio
onda A PW-Doppler MV) il RIAD (“timing” onda
P/inizio onda A PW Doppler TV).
162. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
(Padeletti) studio condotto sugli
Effetti OAVD e concetto di RIAG mediante pacing
ADx basso (SIA e triangolo di KOCK) con effetti di
RIDUZIONE del RIAG mediante sincronizzazione
dell’attività delle due camere atriali, senza interferire
con la fase di riempimento diastolico delle due camere
ventricolari (Starling, senza modificare SV/CO).
163. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
PRESUPPOSTO della CRT:
Alterato SINCRONISMO A-BIV ( IVCD/RCIV/AVD)
responsabile di un PEGGIORAMENTO emodinamico
(Dp/Dt).
RAZIONALE della CRT:
Possibilità di INVERSIONE delle conseguenze delle
asinergie, con risultante miglioramento emodinamico
I TRE MECCANISMI di ASINERGIA sono operativi
nella maggior parte dei pazienti con BBSx
164. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Studi iniziali con “coil” epicardico
Studi successivi con “coil” trans-venosi standard per
RVA.
Studi successivi con specifici “coil” per il CS
165. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• Segnalazioni di efficacia ANEDOTTICHEANEDOTTICHE
• Valutazioni SUCCESSIVE di tipo EMODINAMICAEMODINAMICA
• BASSOBASSO valore PREDITTIVOPREDITTIVO studi iniziali
• Supposto miglioramento in ACUTOACUTO non confermato
in CRONICOCRONICO
• DUBBIADUBBIA la natura investigativa e la validità
scientifica degli studi
(“non controllati” e “non randomizzati”)
CONSIDERAZIONICONSIDERAZIONI
effetti a breveeffetti a breve
terminetermine
166. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• Valutazione in ACUTOACUTO dei parametri
EMODINAMICIEMODINAMICI (PA, PP, PCWP, PVC).
• Identificazione INIZIALEINIZIALE dei potenziali
RESPONDERRESPONDER mediante NYHA, QOL e 6-MWT.
• Valutazioni SUCCESSIVESUCCESSIVE della progressione di
malattia (MORBIDITA’ e MORTALITA’).
CONSIDERAZIONICONSIDERAZIONI
effetti a breveeffetti a breve
terminetermine
167. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Cazeau (PACE ’94)
8 pz., NYHA IV, LVEF<30% (22±8%).
“RANDOM” evaluation of 4 different configuration
(RVA, RVOT, RVA/LV,RVOT/LV)
BVP improved SV/CO (20-25%), PCWP (19-23%), IVCT/IVRT
(13±9%).
Bakker (PACE ‘94)
A-BVP in 5 pz. CMD/HF, NYHA III-IV, BAV I, epicardial
“lead”. 4/5 (80%) improved NYHA, LVEF (m.v.8±2%),
SV (12±3 ml), VTI MV, M.R. and OAVD (?)
EARLY APPROACH
168. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Leclercq (JACC ’98)
18 pts CHF, NYHA III-IV, QRS>120ms (170±37ms), OMT.
Evaluation 4 different PACING configuration
AAI, DDD (RVA/RVOT) e BIV (LV/RVA e LV/RVOT)
RVA/RVOT
META-ANALYSIS: BVP improved in 12/18 pts (66%) CI and
PCWP
Parametri EMODINIAMICI ed ECG non predittivi della
risposta alla CRT (elemento discriminante LVEF basale più
bassa nei “responder”)
169. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
(Auricchio, Circulation ’99)
Studio 27 pz CMD/HF (PATCH-CHF), NYHA III-IV,
LVEF ≈20%, RS, QRS>120ms e PR>150ms
(“lead” epicardico).
Tre diverse configurazioni di pacing (VDx, VSx e BV)
Differenti AVD.
22/27 (81%) miglioramento Dp/Dt, PA sistolica e PP.
“RESPONDER” identificabili per QRS basale più stretto
(128±12 versus 180±22ms).
Effetto EMODINAMICO dipendente da OAVD
OAVD specifico per ogni paziente
Effetti EMODINAMICI ampio “RANGE” (80-200ms)
170. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
(Kass, Circulation ’99)
18 pazienti, NYHA III-IV, LVEF 19%, QRS>150ms.
Analisi Dp/Dt, PA sistolica e PP
Differenti configurazioni di pacing
(RVA, RVOT, LV, BV).
Correlazione positiva QRS basale e +Dp/Dt
Miglioramenti VTI mitralico e Dp/Dt con OAVD
(“range” 90-130ms per migliore pre-carico)
Effetti DETRIMENTALI AVD<90ms
PV “loop” migliore nella configurazione LVP
(Yu, AHJ ’03)
Configurazione CRT azione sui parametri di fuzione
SISTOLICA REGIONALE (DTI) e su MR anche
rispetto alla configurazione LVP.
171. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• Risposta individuale VARIABILE
• Efficacia su funzione SISTOLICA globale
• LVP ≥ BVP su PV “LOOP”
• MIGLIORAMENTO funzione SISTOLICA regionale
• Effetto combinato con OAVD (fase DIASTOLICA)
• OAVD specifico per ogni individuo con effetti
positivi in un determinato “RANGE”, al di fuori del
quale vengono perduti i benefici emodinamici.
• “RESPONDER” QRS basale largo e LVEF più
depressa.
• EMODINAMICA non sempre correlata all’ECG.
EFFETTI CRT A BREVE TERMINE
172. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• Attivazione ventricolare ASINCRONAASINCRONA
• REDISTRIBUZIONEREDISTRIBUZIONE carico di lavoro
(tensione parietale) regionale (WMSI) con
modifica della PERFUSIONE e ripartizione
MBF/VO2.
• RIDUZIONE MBF/VO2RIDUZIONE MBF/VO2 zone con precoce
attivazione
• AUMENTO MBFVO2AUMENTO MBFVO2 zone con tardiva
attivazione
Effetti STIMOLAZIONEEffetti STIMOLAZIONE
RVA/RVOTRVA/RVOT
173. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• VARIAZIONIVARIAZIONI IL-GF dei cardiomiociti
Effetti STIMOLAZIONEEffetti STIMOLAZIONE
RVA/RVOTRVA/RVOT
• Progressiva DILATAZIONEDILATAZIONE VSx
(LVEDV e LVESV)
• Sviluppo di ipertrofia ASIMMETRICAASIMMETRICA
(collagene)
174. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• Applicazione “STANDARD”“STANDARD” nella
INCOMPETENZAINCOMPETENZA cronotropa (normalizz. FC)
• Fenomeni ADATTATIVIADATTATIVI nel BAV completo
• Alterata funzione MECCANICA e progressivo
sviluppo di IPERTROFIA BVIPERTROFIA BV
• Progressiva RIDUZIONERIDUZIONE SV/CO
Effetti STIMOLAZIONEEffetti STIMOLAZIONE
RVA/RVOTRVA/RVOT
175. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• Relazione NEGATIVANEGATIVA nel
rapporto FORZA/FREQUENZAFORZA/FREQUENZA
• Modificazioni OMEOSTASIOMEOSTASI Ca++ con
prolungamento fase di ripolarizzazione
cellulare (QTc lungo) e aumentato rischio di
aritmie ventricolari.
Effetti STIMOLAZIONEEffetti STIMOLAZIONE
RVA/RVOTRVA/RVOT
176. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Induzione BAV completo (13 cani)
Valutazioni ECHO per 8 settimane
Randomizzazione in doppio cieco a RVP o BVP
(VDD e AVD 100ms)
Analisi funzionale/morfologica ECHO dopo 8 settimane
post BAV completo
Durata QRSc e QTc
Rapporto indici di MASSA VSx tra SIV e PP
Misurazioni PAMc/FC VSx/VDx e P. VSx , mediante
elettrodo quadripolare endocardio e misurazione
P.VSx (calcolo del Dp/Dt)
Effetti STIMOLAZIONEEffetti STIMOLAZIONE
RVA/RVOTRVA/RVOT
177. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• Dopo il BAV e prima della RANDOMIZZAZIONE
sviluppo ipertrofia ASIMMETRICA VSx (>25%) e
incremento LVEDV/LVESV (>45%)
• Al termine della RANDOMIZZAZIONE progressiva
regressione degli indici di massa (2 settimane/BVP
6 settimane/RVP)
• BVP REGRESSIONE dell’ipertrofia più uniforme
(rapporto SIV/PP ≈1)
• Riduzione LVEDV/LVESV in entrambi i gruppi.
• Rimodellamento MECCANICO con normalizzazione
del carico di lavoro e miglioramento del sincronismo
178. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Effetti del RVP e BVP nel’incompetenza cronotropa
legati ad un RIMODELLAMENTO INVERSO
Effetti di tipo CONTRATTILI e STRUTTURALI.
Non è possibile il RIMODELLAMENTO ELETTRICO
(QTc e QRSc non si normalizzano come la MASSA)
Il rimodellamento si associa a variazioni di +Dp/Dt,
LVEDV e LVESV VSx.
Regressione dell’ipertrofia più rapida ed uniforme
con il BVP
• Effetti EMODINAMICI del pacing dipendenti dalla
configurazione utilizzata (RVP/BVP)
• Il grado di IPERTROFIA ASIMMETRICA raggiunto
dipende dal SITO di STIMOLAZIONE utilizzato
179. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Risultati CLINICI eterogenei del CRT
Percentuale variabile “NON RESPONDER” (25-30%)
Criteri di selezione NON UNIFORMI
Linee guida AHA/ACC/NASPE continuamente messe in
discussione dai risultati di nuovi trial
Maggiori effetti della CRT nei pazienti in classe
NYHA III ed in fase di stabilità clinica
Risultati minori se classe NYHA troppo avanzata (IV),
comorbidità associata e/o necessità di inotropi ev
180. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
CRITERI condivisi (MIRACLE)
CMD/HF primitiva o ischemica
Classe NYHA III-IV nonostante OMT
Criterio ECG di QRS>120ms
Criterio ECHO di LVEDD>55mm ed FE<35%.
Recenti META-ANALISI riferite ai principali trial
condotti considerano non più necessario il criterio ECG
ma sufficiente la diagnosi ECHO di RCIV (IVCD/OAV)
181. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Ridotta efficacia clinica nei pazienti particolarmente
compromessi (NYHA IV) ed emodinamicamente
instabili (inotropi ev)
Eventuale allargamento ai pazienti NYHA II se
candidabili all’impianto di un dispositivo DDD/VVI (R)
convenzionale e presentano alcuni marker
ECHO (LVEDD>55mm, PW restrittivo/pseudo-N, MR)
ECG-grafici (VTS/VTNS CRT+ICD)
TERAPEUTICI (titolazione non adeguata per AVD)
182. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
CRITERIO ECG
Relazioni ASINCRONIE/durata QRS
HP di partenza:
(1) ASINCRONIE scontate se QRS>120ms
(2) Correlazione diretta CMD/HF, BBSx e mortalità
(3) Criterio ECG specifico ma non sensibile
(4) Mancanza di “cut-off” point
(5) Ampia variabilità range 120-170ms
183. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• Correlazione INVERSA tra durata QRS e
riduzione
LVEF
• Buona correlazione se QRS>170ms (molto
specifico)
• Bassa correlazione se QRS<100ms (poco sensibile)
• Nessuna correlazione se QRS>100ms e <170ms
• Concetto della DISPERSIONE del QRS
CORRELAZIONE QRS/LVEF (CMD/HF)
Buona correlazione QRS/IVCD
Scarsa correlazione QRS/RCIV (marker della CRT)
184. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
In alcuni Lavori le percentuali di mortalità sono
sovrapponibili se si utilizza il solo parametro QRS ed il
“cut-off” point di 120ms)
Diversi lavori hanno dimostrato una DISTRIBUZIONE
di tipo UNIMODALE della durata QRS nei pazienti
CMD/HF, ossia senza “CUT-OFF” point per valori
compresi tra 70 a 180ms (Xiao (BHJ ’92):
185. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• Software applicativi (DTI) dimostrano
l’ ASSENZAASSENZA di correlazione assoluta
QRS/RCIV
Metodica ECHOMetodica ECHO
• META-ANALISIMETA-ANALISI del PATH-CHFPATH-CHF dimostra
come la popolazione arruolata nel trial
(QRS>120ms) presentava diversi quadri di
RCIV che andavano dalla competa assenza alla
presenza di un IVCD.
186. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
IMPATTO METODICA ECHO
• JACC del ’03 pazienti CMD/HF idiopatica con
PREVALENZA del parametro RCIV 92% nel
BBSx+EAS, 46% nel BBSx, 78% nel BBSx
incompleto, 48% nell’EAS e 41% nel QRS normale.
• Efficacia della CRT nei pazienti BBDx
(analisi DTI di coesistenti RCIV VSx)
187. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Effetti EMODINAMICI della CRT presenti sia nei
pazienti con IVCD che in quelli con QRS<120ms.
Estrema variabilità dei valori di “cut off”, alcuni dei
quali troppo alti (>150ms).
Variabilità dei parametri “TARGET”
nel trial PATCH CHF II gli effetti EMODINAMICI
(V02 di picco ed alla soglia anaerobica e 6MWT) in ACUTO
ed a 3 mesi di FU erano presenti solo nella QRS>150ms
Dopo 1 anno di FU effetti presenti in ambedue i gruppi.
Un QRS stretto non esclude le ASINERGIE
Un QRS largo non garantisce le ASINERGIE
188. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
INDICAZIONI AMPIAMENTE CONDIVISE
(criteri MIRACLE)
CMD/HF di qualsiasi etiologia
LVEF<35%
(non esistono studi clinici randomizzati con valutato
degli effetti della CRT nei pazienti con LVEF>35%).
classe NYHA III o IV nonostante OMT.
Criteri in parte rivisti e corretti, nel senso che è
oramai ampiamente condiviso che il criterio di selezione
PRINCIPALE dei pazienti CRT ritiene necessaria e
sufficiente la diagnosi ecocardiografica di RCIV e
IVCD.
189. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Analisi degli effetti CRT a partenza dai
“NON RESPONDER”
• Inaccurata SELEZIONE del campione
• Presenza di CO-MORBIDITA’
(BPCO, insufficienza renale, ipertensione
polmonare con HF Vdx)
• Classe NYHA troppo avanzata (IV)
• Grave instabilità emodinamica
Più utile valutare la presenza di IVCD con metodica
ECHO che desumerle sulla base dell’ampiezza del QRS.
190. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Wide variability of QRS duration in a board
spectrum (no “cut-of” point)
Non Responder
Witch is the “target” site for CRT ?
Witch is the implication in class NYHA II ?
And in class NYHA IV with “unstable”
haemodinamic profile ?
Is possible CRT in Atrial Fibrillation’s pts ?
Is it possible CRT in Right Bundle Branch
Block’s patients ?
INDICAZIONI DISCUSSE:
191. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• Nei pazienti CMD/HF, il criterio DURATA del QRS
presentava una relazione INVERSA con la LVEF.
• Un QRS>170ms identifica una condizione di
riduzione riduzione della LVEF (Murkofsky)
• Il QRS è un criterio molto specifico per ridotta
LVEF e IVCD, ma poco sensibile per RCIV
192. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Mancanza di un “cut-off point” standardizzato
(1) COMPANION, il CONTAK CD, PATH CHF I e II
QRS>120ms
(2)BELIVE, INSYNC ICD e MIRACLE (+M-ICD)
QRS>130ms
(3)INSYNC, MUSTIC e PACMAN
QRS>150ms
(4)CARE HF
QRS>150ms (QRS>120ms se RCIV all’ECHO)
193. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Il limite di alcuni lavori (e mi riferisco non solo a
quelli iniziali condotti da Murkofsky)
Il criterio QRS largo presenta una notevole
correlazione con LVEF per valori >170ms, ma la
maggior parte dei lavori pubblicati in letteratura
utilizza “cut-off”point anche molto più bassi.
Altri lavori includono nella popolazione in esame
pazienti con QRS di ampiezza variabile da 80 a 124
ms, valori molto lontani da quelli proposti come
indicazione alla CRT.
194. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Un QRS<100ms non esclude una anormale LVEF ed
(QRS prolungato nel 43,8% con ridotta LVEF e nel
16% con LVEF normale.
La durata del QRS può differire notevolmente nelle
diverse derivazioni.
Il QRS è più lungo negli uomini che nelle donne.
La durata del QRS si correla con le dimensioni del
cuore.
195. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Estrema VARIABILITA’ del criterio durata del QRS
nei pazienti con CMD/HF anche in ECG seriati.
Kervin: analisi dele relazioni esistente tra IVCD e
durata del QRS>120ms. Il miglioramento di tale
asincronia durante CRT correla un aumento di LVEF in
acuto.
I pazienti CMD/HF con QRS<120ms presentavano
gradi minori di IVCD.
AMPIEZZA del QRS non è PREDITTIVA del
miglioramento di LVEF dopo CRT.
196. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
MECCANISMI di AZIONE della CRT (ECHO)
• Contrazione ventricolare più omogenea.
• Prolungamento del riempimento DIASTOLICO
effettivo
• Riduzione delle pressioni di riempimento (PTDVSx).
• Riduzione del grado di MR
• RIDUZIONE del PEP.
197. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Analisi degli EFFETTI EMODINAMICI della CRT
mediante impiego di dispositivi in grado di
effettuare un Monitoraggio Emodinamico Continuo
(MEC), mediante un sensore di PRESSIONE che
sfrutta il principio della CAPACITANZA variabile
(inverso della resistenza) per misurare la pressione
assoluta.
Analisi di PTDVDx, PTSVDx , PAD polmonare
(derivata dalla PVDx all’acme del Dp/Dt, ossia al
momento dell’apertura della polmonare), il (Dp/Dt),
FC, attività adrenergica (HRV) e temperatura.
198. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Le LINEE GUIDA non considerano adeguato
proporre ai pazienti NYHA II la CRT.
Di contro alcuni lavori documentano risultati positivi
di efficacia (classe NYHA e 6-MWT).
A tutt’oggi, comunque, appare plausibile proporre la
CRT ai pazienti NYHA II se LVEF<35% ed indicazione
a PM tradizionale (possibile ulteriore
desincronizzazione VSx), oppure se presenti altri
marker di rischio (LVEDD>55mm, MR severo, E/A
restrittivo o pseudo-N).
Risultati di uno studio condotto “in acuto” su 16
pazienti con disturbi della conduzione AV e normale
LVEF, nei quali il RVP deprima Dp/Dt rispetto al BVP.
199. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
E’ in corso uno studio controllato (PREVENT HF), con
lo scopo di valutare l’efficacia della CRT nei pazienti
con LVEF ridotta ed indicazione ad impianto di PM
tradizionale.
Effetti della CRT nei pazienti CMD/HF sotto il
profilo funzionale, e quindi come miglioramento del
quadro clinico inteso come classe funzionale (NYHA),
e della QOL (Minnesota)
200. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
PATH CHFPATH CHF
significativo miglioramento di QOL (34%) e classe
NYHA (26%) nel 63% dei pazienti, con persistenza
degli effetti a distanza di 12 mesi di FU.
QOL E CLASSE FUNZIONALE:
MIRACLEMIRACLE
453 pz, significativo miglioramento di classe NYHA e
QOL, dei CRT rispetto ai CTR
201. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
MIRACLE-ICD
a 6 mesi FU miglioramento classe NYHA del 63% nei pz CRT
e del 47% nei pz CRT-off Miglioramento QOL di 19 punti nel
gruppo CRT e di 10 punti nel braccio non CRT.
CONTAK CD
miglioramento di classe NYHA e QOL a 6 mesi di FU nel
gruppo pz HF e NYHA III/IV). Il 73% dei pz che ricevevano
CRT mostrava un miglioramento di almeno una classe NYHA
confrontata con il gruppo non-CRT. La QOL a 6 mesi
migliorava di circa 10,1 punti confrontata con i CTR.
202. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Anche se questi studi differiscono nel design
(presenza di “crossover” o studio in parallelo)
la CRT sembra avere un effetto favorevole su
STATO FUNZIONALESTATO FUNZIONALE e QOLQOL.
Gli effetti PIU’ MARCATIPIU’ MARCATI nei pazienti
CMD/HF con sintomi più importanti (classe
NYHA III/IV).
203. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
VO2 e CAPACITA’ ALL’ESERCIZIO (6-MWT)
Considerati gli iniziali INDICI di efficacia CRT
(MIRACLE,MIRACLE ICD e CONTAK CD)
1. 6-MWT (20m40m), parametro influenzabile da
effetto placebo, allenamento o risposta familiare.
2. tolleranza all’esercizio (NYHA)
3. Consumo di Ossigeno (VO2) (1-2ml/Kg/min).
MIRACLE riduzione pendenza del rapporto VE/VCO2
• Criterio più obiettivo (non è motivazione dip.)
• Espressione di una risposta metabolica favorevole
• Non differenze significative sulla VO2 alla alla
soglia anaerobica.
• Associata a miglioramento della capacità esercizio
204. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
VALUTAZIONE della
PROGRESSIONE di MALATTIA
Analisi deL RIMODELLAMENTO INVERSO
MORFOLOGICA: dimensioni, forma, volume, massa
VSx e dimensioni ASx
FUNZIONALE: LVEF, MPI, MR, DT, Qp/Qs, E/A
NEURO-ORMONALE
DIRETTA: misurazione concentrazioni NE, E,
BNF, Dopamina, Grande Endotelina
(VIGOR HF primo trial US con valutazione effetti
CRT su livelli NE)
INDIRETTA: parametri HRV (surrogato)
205. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
VIGOR-HF:
primo trial negli USA con “lead” epicardico, con 3
mesi di BVP continua, con riduzione dimensioni (1)
ASx (70% dei pazienti) e (2) LVEDD e LVESD, LVEDV
e LVESV (80% dei pazienti)
CONTAK CD:
CRT non effetti su variabilità neuro-ormonale ed HRV
(>50% pts trattati con β-bloccanti).
La sospensione della CRT dopo un mese provocava una
inversione degli effetti positivi precedentemente
osservati sulle strutture cardiache.
206. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
CRT ed indici di sopravvivenza
CRT non provoca un incremento della mortalità.
End-point primario del CONTAK CD rappresentato
dalla progressione dell’HF (insieme di mortalità,
ospedalizzazioni ed eventi VT/VF).
Studio COMPANION ideato per valutazione
effetti su tutte le cause di mortalità.
CRT e MORBIDITA’ / MORTALITA’
207. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
MODALITA' DI STIMOLAZIONE:
BVP vs LVP
• I risultati degli studi iniziali (in acuto e non
controllati) mostravano una sostanziale
equivalenza tra le due tecniche sui parametri
EMODINAMICI (Leclercq e Blanc) o effetti
superiori del LVP (Cass, Auricchio).
• Questi risultati sono stati confermati anche
in “FU” a breve termine (Cazeau).
208. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
MODALITA' DI STIMOLAZIONE:
BVP vs LVP
• Altri lavori (Touiza - JACC '01), “non
randomizzati” e condotti su piccole “coorti” (33
pts) confermavano una sostanziale equivalenza
sui classici “end-point”
(NYHA, LVEF, M.R., 6-MWT e VO2 peak),
mentre la riduzione del LVESD era più
marcata con il BVP.
• Anche Garrigue e coll (Heart '02), in uno
studio prospettico tra pazienti HF in FA,
permetteva di osservare nel confronto una
superiorità del BVP.
209. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• La CRT esplica una azione elettro-meccanica
a diversi livelli (A-A delay, AV, RCIV, IVCD,
V-V delay).
• Effetti emodinamici maggiori con CRT del
RCIV (LVP e BVP), mentre CRT dell’IVCD
possibile solo con BVP.
• Yu ed Auricchio (PACE '00) evidenziano come
la massima CRT dell’IVCD non si correla con
il maggior beneficio emodinamico, mentre
CRT del RCIV si correla con l’emodinamica.
210. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• “EBM” supporta uso routinario della CRT
quale trattamento aggiuntivo nei pazienti
CMD/HF e classe NYHA III-IV nonostante
una OMT.
• Studi sulla CRT con BVP in pts in R.S. ed FA
suggeriscono che la CRT, migliorando entrambi i
gruppi, ha un effetto prevalente su RCIV e IVCD
rispetto all’OAVD.
• Concetto di riserva di CRT.
211. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
CRT ed ASSOCIAIZONE con ICD
ARITMOGENICITA’ nei PAZIENTI CMD/HF
• Potenziale di azione cellulare particolarmente
lungo (QTc dispersion), che predispone a post-
potenziali (precoci/tardivi) e quindi VT.
• Alterazione dei meccanismi di accoppiamento
elettrico a livello inter-cellulare, come risultato
del rimodellamento delle gap-junction.
• Attivazione dei mediatori dell’infiammazione
con alterazione dell’interstizio cellulare e
comparsa di ritardi nella conduzione dell’impulso
elettrico fino alla comparsa di aree di blocco
funzionale/anatomico.
212. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• Fenomeni che predispongono a A-A delay, IVCD,
RCIV, AVD, V-V delay.
• Prolungamento della durata del potenziale di
azione e della fase di ripolarizzazione cellulare.
• Prolungamento della durata del potenziale di
azione con (1) “down-regulation” corrente
ripolarizzante di K+, (2) “up-regulation” della
corrente depolarizzante del canale ionico legato allo
scambiatore Na+/Ca++ e (3) modifiche
nell’attivazione dei canali del Na+ voltaggio-dip.
CRT ed ASSOCIAIZONE con ICD
ARITMOGENICITA’ nei PAZIENTI CMD/HF
213. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• Dispersione della durata del potenziale di
azione (differenza tra il potenziale di azione più
lungo e quello più corto), fenomeno frequenza-
dipendente (a FC basse il QRS dispersion è
maggiore).
• Modifiche dell’omeostasi del Ca++
• Innesco di depolarizzazione mediata da
automaticità triggerata da rientri funzionali.
• Modifiche a carico delle proprietà attive della
m.p. con fenomeni di rientro, RCIV e IVCD
legati a modifiche della cinetica di canali ionici.
CRT ed ASSOCIAIZONE con ICD
ARITMOGENICITA’ nei PAZIENTI CMD/HF
214. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
INDICAZIONI NON UNIVOCHE CRT+ICD
DUPLICE PUNTO DI VISTA
• Valutazione benefici ICD nei candidati a CRT.
Se indicazione di classe I per ICD il problema
non sussiste, ma i trial INSYNC ICD e
COMPANION suggeriscono l'utilità anche nei
pazienti non in classe I ed inoltre i risultati del
MADIT II consigliano l'uso di un ICD come
“back-up” qualora sia necessaria al CRT nei
pazienti CMD post-ischemica.
CRT ed ASSOCIAIZONE con ICD
ARITMOGENICITA’ nei PAZIENTI CMD/HF
215. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Indicazioni ad eventuale CRT nei candidati
ad ICD e senza CHF conclamato.
DISCUSSIONE: se si allargano i criteri ai pazienti
di classe II e se e, prevedibile un peggioramento
clinico a quei pazienti con LVEF depressa ed a
quelli con RVP
Infatti il MADIT II, nel braccio nel quale i pazienti
CAD ed FE,30%, impiantati con ICD, nel follow up
presentavano una maggiore
incidenza/peggioramento HF. Mortalità HF per
(1) deterioramento della funzione di pompa (2)
SCD per aritmie letali (causa prevalente di SCD
nei pazienti in classe NYHA II/III). ICD quale
strumento per ridurre le SCD dovute VT/VF.
216. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• HP a favore dell’ICD per prolungare la
sopravvivenza nei pazienti HF e LVEF marcatamente
depressa.
• HP contro l’ICD per persistenza delle SCD
nonostante l’ICD, per dissociazione
elettromeccanica.
MADIT I, i pts con CAD, LVEF≤35%, VTNS
asintomatiche e VTS/VF allo SEE, presentano indici
di sopravvivenza migliori con OMT+ICD rispetto ad
OMT.
MUSTT negli stessi pts (LVEF≤40%) benefici simili
con ICD.
Nel CABG Patch Trial, studio di prevenzione primaria
217. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
MADIT II
(pazienti con IMA pregresso, LVEF≤30% ed OMT)
ICD riduce la mortalità globale durante un periodo
medio di follow-up di 6 mesi (31%).
Indicazione ad ICD in una popolazione molto ampia di
pazienti con pregresso IMA, non con “screening”
elettrofisiologici ma sulla semplice dimostrazione di
una LVEF≤30% (espressione di una eventuale
instabilità del quadro elettrico).
Le implicazioni del MADIT II spingono ad allargare
le indicazioni all’ICD. Attualmente non vi sono
evidenze sufficienti e conclusive che l’ICD da solo
migliori la sopravvivenza a lungo termine dei pazienti
218. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
AUMENTO DELLA MORTALITA’:
Prolungamento QRS associato ad aumentato rischio
di mortalità nei pazienti CMD/HF (INSYNC e VEST)
Evidenze sperimentali suggeriscono una aumentata
mortalità nei pazienti HF con QRS largo legata ad
una aumentata tendenza allo sviluppo di VT, dato
supportato da uno studio condotto su pazienti
sottoposti a SEE nel quale una durata >120ms del
QRS è risultato essere una variabile predittiva
indipendente del rischio di induzione di VT
sostenute e monomorfe
(associazione VT/durata del QRS).
QTc dispersion.
219. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Utilizzo LIMITATOLIMITATO a pz. CHF, NYHA III/IV.
Potenziale ALLARGAMENTOALLARGAMENTO delle indicazioni ad
una fase ancora iniziale della patologia HF.
Potenziale effetto di RALLENTAMENTORALLENTAMENTO della
progressione di malattia).
NYHA II CLASSNYHA II CLASS
220. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• Recente HP del CRT nei pazienti CHF/RBBB
(indice predittivo indipendente come LBBB?)
• HP di IVCD e RCIV a livello del VSx non
evidenziabili all’ECG (RCIV ed IVCD occulti), ma
valutabili con altre metodiche (DTI).
RBBBRBBB
221. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
CRT nei pz. RBBB se associato IVCD.
12 pz. CHF/RBBB e RCIV (DTI)
“FU” 1 year
75% (9/12) miglioramento clinico (treadmill test)
e riduzione RCIV (DTI).
Nei 3/12 (25%) i RCIV (DTI) erano minori.
SUBSETS pz dei trial MIRACLE e CONTAK-CD.
Pz. RBBB profilo di risposta IDENTICO pz LBBB
Garrigue (AHJ ’00)
222. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
• Effetti EMODINAMICIEMODINAMICI CRT legati alla
ottimizzazione sequenza di attivazione elettrica
VSx (DTI) piuttosto che a RIDUZIONE QRS
durante BVP
Prinzer
223. Cardiac Resynchronization TherapyCardiac Resynchronization Therapy
Recupero funzionale di aree ASINERGICHE,
fenomeno non necessariamente correlato a
modifiche della DURATA del QRS ma a modifiche
dell’ ATTIVAZIONE ventricolare
Risultati in alcuni studi hanno osservato come nei
“responder” le variazioni nella RISPOSTA CLINICA
si associavano ad un accorciamento
SIGNIFICATIVO della durata del QRS dopo CRT.
Altri lavori hanno invece supportato l’ipotesi che i
pazienti potrebbero presentare un miglioramento
emodinamico anche senza sostanziali modifiche della
durata del QRS
Editor's Notes
Selection of the appropriate pacing mode to fit the patient’s electrical and haemodynamic status is usually not difficult. Striving to provide both AV synchrony and rate modulation, whenever possible, assists in the decision-making process. Mode selection dicisions related to electrical considerations take into account three principle issues. These are atrial rhythm status, status of AV conduction, and the presence of chronotropic competence. A mode selection flow chart is shown above.
Clinical motivations by the device industry to develop unique algorithms (Search AV, AV Hysteresis, etc.) and/or pacing modes (AAISafeR etc.) to actively manage ventricular pacing were brought about by the well-understood relationship between the electrical-mechanical synchrony required by the heart to maintain optimal hemodynamic performance. Specifically, the atrial chamber contractions provide an important filling contribution to ventricular output. And, coordinated pumping between the left and right ventricles is necessary to achieve adequate ejection fractions. When this AV synchrony and ventricular synchronization is lost, patients may suffer from poor systolic function and low cardiac output.
An avalanche of clinical data is taking shape to support the clinical need of reducing unnecessary RV-pacing and maintaining AV synchrony with physiologic-based pacing modes. Specifically, each of the trials listed on this slide have documented the following:
DANISH II Trial – the objective was to compare single chamber atrial and dual chamber pacing in patients with sick sinus syndrome and normal AV conduction. Patients were randomized to one of three rate-adaptive modes (AAIR, DDDR with a short AV or DDDR with a long AV delay). Primary endpoints were left atrial size and left ventricular size and function as measured my M-mode echocardiography. Results showed that in both DDDR groups, LA diameter increased significantly (p&lt;0.01) and in the DDDR-s group, LVFS decreased significantly (p&lt;0.01). Atrial fibrillation was significantly less common in the AAIR group (p=0.03). The study indicates that long-term DDDR pacing induces LA dilation and, in the case of a high proportion of RV pacing, also reduces LV function. Pacing with 90% RV pacing induced changes identical to the changes observed in the VVI group from the DANISH I Trial. [JACC 2003;42:614-23.]1
CTOPP Trial – the objective was to study the effect of physiologic pacing on the development of chronial AF. Patients undergoing first implant were randomized to AAI or DDD. Results showed that physiologic pacing reduced the development of chronic AF by 27.1% (p=0.016) but did not translate into a reduction in the composite primary endpoint of stroke or cardiovascular death. [JACC 2001;38:167-72.]4
DAVID Trial – the objective was to determine the efficacy of dual chamber pacing (DDDR 70 bpm) compared with backup pacing (VVI 40 bpm) in ICD indicated patients who did not require bradycardia pacing. The main outcome to measure was the composite endpoint of time to death or first hospitalization for CHF. Results showed that the VVI group had fewer occurrences of the composite end point (p0.03). However, the component endpoints of death and CHF hospitalization did not individually reach statistical significance. The relationship for %V-pacing in the DDDR group was also studied. Results – patients who survived to the 3-month follow-up had worse 12-month event-free rates when the percentage of right ventricular pacing was 41% to 100% (p=0.09). [JAMA. 2002;288:3115-3123.]5
MOST Trial – this study tested the hypothesis that ventricular desynchronization imposed by right ventricular apical pacing, even when AV synchrony is preserved, increases the risk of heart failure hospitalizations and atrial fibrillation in patients with SND and normal baseline QRS. The trial randomized 2010 patients for 6-year follow-up to DDDR versus VVIR. Results showed that cumalitve time spent in V-pacing was a strong predictor of HF hospitalization in both groups and the riks of AF increased linearly with cumaltive %VP from 0-85%. Additional details on the MOST Trial results follow in subsequent slides. [Circulation. 2003;107:2932-2937.]6
Sweeney, et al. retrospectively studied the cumulative percent of ventricular pacing and the associated relative risk for developing new onset AF. The best models demonstrated a linearly increasing risk of AF with Cum%VP in DDDR and VVIR modes up to approximately 80-85%. The magnitude of increased risk was approximately 1% for each 1% increase in Cum%VP, and was similar between pacing modes.
Key take-away: The rates of AF increased in both the DDDR and VVIR pacing modes. The overall rate of AF was slightly higher in the VVIR group, and the risk of AF increased by 1% for each 1% increase in cumulative %V-pacing (up to 85%) in the DDDR mode.
The shape of the relationship between Cum%VP and risk of HFH was different between DDDR and VVIR pacing modes. The risk was level above a certain Cum%VP (40%) in the DDDR mode and level below a certain percentage (80%) in the VVIR mode.
These results imply that the risk of HFH in the DDDR mode does not increase with further increases in Cum%VP above 40%, but this risk might be reduced to about 2% if ventricular pacing is minimized.
The focus on this slide is on relative risk for heart failure hospitalization in the DDDR group. Note that relative risk for heart failure hospitalization (HFH) cannot be decreased until the cumulative percent of ventricular pacing falls below the 40% mark. That is, even if a physician is able to reduce %VP from 85% down to 45%, the patients relative risk for heart failure hospitalization would still remain the same.
A patient’s risk for HFH is not affected until %VP falls below the 40% mark. Below 40% VP, for each 10% decrease cumulative percent pacing, there is an associated 54% relative decrease in risk in HFH.
Bottom line: Novel algorithms or pacing modes that attempt to reduce cumulative %VP, should strive to reduce the percent VP below the 40% mark. If they are unable to show this type of reduction, the relative risk for HFH is unaffected.
This slide focuses on the VVIR pacing mode. In contrast to the DDDR curve for relative risk of HFH, in the VVIR mode, relative risk cannot be reduced regardless of minimization of ventricular pacing, and this risk is increased by as much as 2.5-fold when Cum%VP exceeds 80%.
HF is a progressive disease with no therapeutic option to cure the illness. This graph shows the correlation between the severity of HF expressed by the 4 NYHA functional classes and survival as well as hospitalization. You can see a very clear decrease of survival (or in other words: an tremendous increase of mortality) and an increase in the frequency of hospital admissions with increasing NYHA function class.
Stroke volume is affected by preload, afterload, and contractility.
Preload is the amount myocardial stretch at the end of diastole.
Afterload is the resistance that needs to be overcome for the heart to eject the blood. There is an inverse relationship between afterload and ventricular function. As the resistance to contraction increases, the force of contraction decreases which results in a decreased stroke volume. Also, as an increase in resistance occurs, there is an increase in myocardial oxygen demand.
Remember, afterload affects cardiac performance throughout ventricular ejection, but preload only affects cardiac performance based on filling at the end of diastole.
Contractility is the inotropic state of the heart independent of the preload and the afterload. It refers to the intrinsic ability of the right or left ventricles to perform pressure-volume work as a pump.
Synergistic LV contraction (ventricular dysynchrony), wall integrity(compliance of the ventricle, infarcted muscle, aneurysm, etc.), and the competence of the valves also affect cardiac output.
LV dysfunction is defined as an ejection fraction of less than 40%. The number one cause of LV systolic dysfunction is loss of myocardium due to a myocardial infarction ( MI, or heart attack).
Pressure overload due to uncontrolled hypertension is another major cause of systolic dysfunction. It is estimated that only 25% of all patients with hypertension are adequately treated.
Impaired contractility also contributes to LV dysfunction and is usually the result of drugs such as alcohol or toxins such as chemotherapy. Volume overload from valvular diseases contribute to LV dysfunction.
LV dysfunction causes decreased cardiac output , which in turn causes hypoperfusion of the body’s organs. In addition, LV dysfunction causes an increase in the amount of blood left in the ventricle when the heart squeezes and therefore both End Systolic and End Diastolic Volumes are subsequently increased. This increase in volume leads to pulmonary congestion and the patient being short of breath.
Key message:
A wide QRS is associated with a poor prognosis.
Additional information:
Baldasseroni: Study to determine whether LBBB associated w/ AF had independent, cumulative effect on mortality for CHF. Analysed 1-yr follow-up data for 5517 pts (63+12 yrs) from Italian Network on CHF (IN-CHF; 150 cardiology centers). Of these, 3328 (60.3%) had neither LBBB nor AF (group A), 1206 (2.9%) had isolated complete LBBB (group B), 798 (14.5%) had isolated chronic AF (group C), and 185 (3.3%) had complete LBBB associated w/ chronic AF (group D). Group D presented greater reduction in functional capacity (NYHA) and more significant clinical impairment (higher rate of pts w/ third heart sound, previous hospitalization for CHF, hypotension and cardiac enlargement). In Group D, cause of CHF was dilated cardiomyopathy (38.4%), ischaemic heart disease (35.1%), hypertensive heart disease (17.3%), and other aetiologies (9.2%). LBBB w/ AF (Group D) was associated w/ increased 1-yr mortality from any cause and sudden death and 1-yr hospitalization rate. Synergistic effect remained significant after adjusting for advanced HF clinical variables. LBBB w/ AF identifies CHF specific population w/ high risk of mortality.
Iuliano: 669 HF pts (ischemic or nonischemic cardiomyopathy, NYHA II-IV heart failure. Median followup of 45 mo. Prolonged QRS was associated w/ increase in mortality (49.3% vs 34.0%) and sudden death (24.8% vs 17.4%). LBBB was associated w/ worse survival but not sudden death.
Masoudi and colleagues used retrospective medical chart data of 19,710 pts Medicare beneficiaries hospitalized w/ HF and for whom LV systolic function was confirmed. LBBB present in 8% of those with preserved LV systolic function (diastolic HF) and in 24% of those with EF &lt; 50% (p&lt;0.001).
Aaronson developed and validated a multivariable survival model for ambulatory advanced heart failure patients wait listed for a heart transplant. IVCD (QRS &gt; 120 ms) present in 27% of the 268 pts in derivation sample, and in 53% of the 199 pts in validation sample. IVCD identified as contributing risk factor.
Other studies have shown that fro the entire HF population about 15% have a wide QRS.
Diastolic BP is the lowest ventricular pressure reached during any given ventricular cycle.
LA LINEA AB RAPPRESENTA L’INCREMENTO DI PRESSIONE E VOLUME IN CORRISPONDENZA DEL RIEMPIMENTO DIASTOLICO, SEGUENDO L’APERTURA DELLA VALVOLA MITRALE (PUNTO a). QUANDO LA PRESSIONE VS SUPERA LAPRESSIONE ATRIALE SINISTRA, SI VERIFICA LA CHIUSURA DI MV (PUNTO B). IL TRATTO BC RAPPRESENTALA FASE DI CONTRAZIONE ISOVOLUMETRICA (IVCT) E QUANDO LA PRESSIONE NEL VENTRICOLO SINISTRO SUPERA LA PRESSIONE AORTICA SI VERIFICA APERTURA AoV (PUNTO C) E L’INIZIO DELLA FASE DI EIEZIONE.
LA LINEA CD DEFINISCE LA PROGRESSIVA RIDUZIONE DI P/V NEL VENTRICOLO SINISTRO. QUANDO LA PRESSIONE VSX CADE AL DI SOTTO DI QUELLA AORTICA, SI VERIFICA LA CHIUSURA DELLA VALVOLA AORTA (PUNTO D) ED INIZIA LA FASE DI RILASCIAMENTO ISOVOLUMETRICO (IVRT). QUANDO LA PRESSIONE VSX SI RIDUCE AL DI SOTTO DELLA PRESSIONE ATRIALE SX, SI VERIFICA LA RIAPERTURA DELLA MITRALE (PUNTO A). IL PUNTO B DEFINISCE EDV/EDP. IL PUNTO D DEFINISCE ESV/ESP
The Frank-Starling mechanism plays an important compensatory role in the early stages of HF, which is demonstrated above.
On the graph, there are three points, A, B, and C. Point A is a healthy patient where cardiac performance increases as preload increases (the amount of stretch on the ventricle before contraction due to an increase in volume).
Point B represents the same individual after developing LV systolic dysfunction. Since the heart is no longer able to contract as effectively as it did, stroke volume falls. As a result, there is a decrease in LV emptying which leads to an elevation of the end-diastolic volume (preload). Since point B is on the ascending portion of the curve, the increased end-diastolic volume initially serves a compensatory role because it leads to a subsequent increase in stroke volume (i.e., more diastolic stretch, the greater the contractility, and the greater the stroke volume...the Frank-Starling mechanism). This however is less than the increase a normal patient would experience.
As the patient’s heart failure progresses (represented by point C), which is on the relatively flat portion of the curve, stroke volume only increases slightly relative to further increases in end-diastolic volume (preload). Here the ability of the Frank-Starling mechanism to compensate for worsening LV function is nearly exhausted. In such circumstances, marked elevation of the end-diastolic volume and end-diastolic pressure results in pulmonary congestion, while decreasing cardiac output leads to increasing fatigue and exercise intolerance. The “flat” part of the curve implies that increases in filling no longer lead to an increase in cardiac output. Eventually, the curve starts downward due to decompensation of the heart muscle.
When cardiac resynchronization (discussed later) is implemented, the hope is to put the HF patient back on top of the curve rather than on the downward slope.
The Frank-Starling law results from the length - tension relation. It results in a volume-pressure relationship.
Note the relationship when afterload and contractility are held constant.
Here, as more volume is added in diastole, the SV increases. The ESV does NOT.
There is an almost linear relationship between afterload and end-systolic volume, called end-systolic pressure-volume relationship (ESPRV). There is an inverse relationship between afterload and ventricular function.
Here, contractility and preload are held constant.
If afterload is increased, LV pressure has to increase. More ventricular work is needed to overcome the resistance to ejection. Less fiber shortening takes place. The stroke volume is decreased.
A positive inotropic agent shifts the ESPVR upward and to the left. This increase in contractility causes an increase in stroke volume and a smaller end-systolic volume.
Main purpose: Remind all of the poor quality of life that burdens heart failure patients
Key messages:
Patients with heart failure have statistically significant impairment of all aspects of their quality of life when compared with other chronic disorders.
Additional information:
From a community screening study involving over 4,000 people in Birmingham, UK.
The SF 36 is a standard quality of life instrument that should be familiar to most clinicians. The lower the score, the more significant is the perceived impairment.
Bakker P, Meijburg H, de Jonge N, van Mechelen R, Wittkampf F, Mower M, Thomas A. Beneficial effects of biventricular pacing in congestive heart failure. PACE 1994;17:820 (abstract 318). CPI study of 5 NYHA Class III/IV pts with DCM, complete LBBB and prolonged PR interval. DDD pacemaker implanted with endocardial RV lead and epicardial LV lead. LV capture lost in 1 pt at 3 months, who had improved initially. 4 pts improved at least 1 NYHA Class at 3 months.
Cazeau S, Ritter Ph, Lazarus A, Gras D, Backdach H, Mundler O, Mugica J. Multisite pacing for end-stage heart failure: early experience. PACE 1996;19[II]:1748-1757. Initial experience on 8 pts with wide QRS (mean 200 35 ms) and end-stage HF (NYHA Class IV) with biventricular pacing including 5 pts with transvenous LV system.
Daubert JC, Ritter Ph, Gras D, Pavin D, Cazeau S, Mabo Ph. Use of specifically designed coronary sinus leads for permanent left ventricular pacing: preliminary experience. PACE 1997; 20[II]:? (NASPE abstract 17). 15 pts, mean follow-up 6 months (2-10) with either model 2188 or custom 2879 (2188 with different bend) implanted in the LV. Successful implant in 11 pts (73%). 1.3±0.7 V pacing threshold acutely vs. 1.9±1.0 V threshold chronically. No lead dislodgment or other lead-related complication was observed. “In conclusion, this preliminary experience is encouraging in terms of feasibility, safety and long term results. Further improvement in lead configuration is needed to increase implantation success rate.”
Gras D, Mabo Ph, Tscheliessnigg KH, Pedersen AK, Tang T. Early results regarding implant procedures of a new biventricular atrial synchronized pacing system. PACE 1998; 21[II]:824 (NASPE Abstract). 18 DCM pts. 16 successful implants (89%), 14 in lateral vein, 2 in GCV. Total procedure duration: 101 35 min. Fluoroscopic time: 24 12 min.
Lurie K, , Benditt D, Samiah N, Blanc JJ. A transvenous “Long Guiding Sheath” technique for permanent left ventricular pacing lead implantation in patients with heart failure. Circulation 1998; 98[17]: I-841 (abstract 4414). Report on use of a 45 cm radiopaque peel away introducer sheath by Daig for LV lead placement. The steps: 1) sheath is placed in SVC as introducer; 2) EP catheter (Daig CSL) is put through the sheath and introduced into the CS; 3) A venogram is obtained using the EP catheter; 4) sheath is advanced over the EP catheter into the CS; 5) EP catheter is removed; 6) LV lead (std RV leads used) is placed through the sheath into the CS. 80% success rate with no complications in 20 pts.
Till now The Registry has enrolled 190 pts, mostly males and aged between 60 and 75. All of them had a history of dilated cardiomiopathy with an average LVDD of 71 mm an an EF of 25%. The average QRS duration 170 msec.
The functional capacity was significantly compromised both in terms of NYHA class and of 6min W. Test
17% of the patients were in CAF
All of the ethiologies of dilated cardiomyopathy were represented in our population
Key Point:
MIRACLE was designed to assess the treatment effect of cardiac resynchronization by minimizing the bias associated with a device-based therapy trial.
Other Information:
Following a period of stable medical therapy and a baseline assessment to determine eligibility, patients underwent an implant attempt.
Implant included an InSync cardiac resynchronization device
Three pacing leads. Standard right atrial and right ventricular; special left ventricular lead implanted transvenously via the coronary sinus
Randomization at pre-discharge to Control group (no pacing) and depicted in white, or CRT (atrial-synchronized biventricular pacing mode) depicted in yellow.
Randomization occurred in permuted blocks to help ensure balance between groups by center.
Patient and heart failure specialist were blinded.
HF specialist made decisions about heart failure management.
Performed efficacy study evaluations.
Electrophysiologist served as an unblinded third party.
Evaluations at 1, 3 and 6 months.
Crossover to CRT prohibited, except for patients who developed a bradyarrhythmia.
Maintenance of background HF medication.
Control group patients crossed over to cardiac resynchronization therapy after 6 months.
Requirement to follow patients ended with device approval in August 2001.
Intention to treat analysis; patients who crossed over were analyzed according to their original treatment assignment.
All are inter-group comparisons (Control vs. CRT).
To minimize bias, core laboratories assessed neurohormonal (Mayo Clinic), echocardiographic (U of Penn), and cardiopulmonary exercise (U of Cincinnati) test results.
Key Points:
Overall, the attrition rate for this study was very low.
Of the 453 patients who participated in the 6 month study protocol, 225 were randomized to control, and 228 to cardiac resynchronization (CRT).
Of those, 201 Control group patients and 215 CRT group patients completed their 6 month follow-up visit.
Additional information:
7 patients did not maintain their assignment to cardiac resynchronization: 4 due to brady indication, 3 due to worsening HF. Data included based on intention to treat principle, therefore these patients are considered in the Control group for the analysis.
Key Points:
Patients averaged 300 meters at baseline, consistent with NYHA Class III/IV heart failure.
There is a favorable treatment effect on this measure of sub-maximal exercise performance as early as one month that is sustained through the 6 month randomization period.
Additional Information:
Values displayed are paired median changes from baseline with the 95% upper and lower confidence intervals at the specified follow-up periods. Control is represented by the solid white circle, CRT by the solid yellow diamond. All data are paired; data for the same patients are shown for each time point.
P-values are based on the comparison of between group changes.
All 6 minute walk tests were supervised by a trained clinician who was blinded as to the patient’s randomization group.
Key Points:
Patients averaged 300 meters at baseline, consistent with NYHA Class III/IV heart failure.
There is a favorable treatment effect on this measure of sub-maximal exercise performance as early as one month that is sustained through the 6 month randomization period.
Additional Information:
Values displayed are paired median changes from baseline with the 95% upper and lower confidence intervals at the specified follow-up periods. Control is represented by the solid white circle, CRT by the solid yellow diamond. All data are paired; data for the same patients are shown for each time point.
P-values are based on the comparison of between group changes.
All 6 minute walk tests were supervised by a trained clinician who was blinded as to the patient’s randomization group.
Key Points:
68% of CRT patients improved by one or more functional class compared with 38% of Control patients. The difference is highly statistically significant.
An improvement in the Control group patients was expected. Drug trials, including the study of carvedilol in moderate to severe heart failure patients, show modest improvement in NYHA functional class for placebo group patients.1
Additional information:
The NYHA functional classification was determined by a physician who was blinded to how the patient was randomized.
Reference:
1. Packer M, et al for the PRECISE Study Group. Double-Blind, Placebo-Controlled Study of the Effects of Carvedilol in Patients With Moderate to Severe Heart Failure Circulation. 1996;94:2793-2799.
Key Points:
Pre-specified objective met as all primary efficacy endpoints had a P0.05.
The magnitude of the effect on the primary efficacy endpoints was not affected by the use of a beta-blocker, by whether the heart failure was of ischemic or non-ischemic origin, whether the intraventricular conduction delay was a left or right bundle branch pattern, or by the duration of the QRS.
Key Points: (Note – a subset of the 453 patients provide the paired data)
Peak VO2 had virtually no change in the Control group of patients compared with a 1.1 ml/kg/min improvement for CRT group patients. The treatment effect was statistically significant.
Total exercise time during the cardiopulmonary exercise test showed similar results. A modest average improvement by Control group patients was overshadowed by an increase of over 1 minute by the patients receiving CRT.
Other Information:
Cardiopulmonary exercise results were assessed by a core laboratory (University of Cincinnati).
All data are paired; data for the same patients are shown for each time point.
Key Points: (Note – a subset of the 453 patients provide the paired data)
Measures of both cardiac function and cardiac structure showed improvement with cardiac resynchronization.
A 4.6 percentage point improvement in LVEF within the CRT group of patients contrasted significantly with a reduction of 0.2 percentage points in the Control group.
Likewise, patients receiving CRT showed a reduction in mitral regurgitation (-2.7 cm2)that was statistically significantly greater than the modest improvement (-0.5 cm2) observed within the Control group of patients.
The reduction in left ventricular end diastolic diameter of 3.5 mm for CRT patients was significant compared with no change on average for Control group patients.
Other Information:
Echocardiographic results are from a single observer at a core laboratory (University of Pennsylvania).
All data are paired; data for the same patients are shown for each time point.
While ventricular pacing spikes were often observed on the simultaneously recorded ECG, each echo study was blinded with regard to identity and analyzed individually and without reference to echocardiographic images or knowledge of measurements from other studies of the same patient.
Key Point:
67% of the CRT patients showed improvement in their composite response at 6-months compared to 39% of the Control patients. The difference is statistically significant.
Additional Information:
Unlike previous endpoints reported that analyze only those patients completing the 6 month randomization period, this measure accounts for the status of all patients randomized.
The Composite Response has emerged as an important secondary endpoint of this study. It is the only endpoint, other than mortality, that takes into account all 453 patients.
A patient is defined as improved if they improved 1 or more functional classes (by blinded physician), or if the patient indicated a moderate or marked improvement in the patient global assessment score.
With the global assessment, the patient answers how they felt since the InSync system was implanted. There are seven possible responses:
Markedly Improved, Moderately Improved, Mild Improvement, No Change, Slightly Worse, Moderately Worse, Markedly Worse.
A patient is said to have worsened if they died, were hospitalized for worsening heart failure since implant, if they crossover from their assigned group because of worsening heart failure, if they withdraw consent, if they had a worsening of NYHA Functional Class, or if they indicated a moderate/markedly worse ranking on the global assessment.
A patient is said to have not changed if the improved or worsened conditions are not met.
Reference:
Packer M. Proposal for a new clinical endpoint to evaluate the efficacy of drugs and devices in the treatment of chronic heart failure. J Card Fail 2001;7:176-182.
The MIRACLE study was not powered to study mortality. However, you can conclude from the results here that cardiac resynchronization does not worsen survival.
Main purpose: Demonstrate evidence of left ventricular reverse remodeling.
Key messages:
Following 3 months of chronic cardiac resynchronization, LV volumes return slowly to baseline, pre-implant levels after the device is turned off indicating reverse remodeling.
On the other hand, mitral regurgitation increases acutely, a finding corroborated by Breithardt and colleagues (J Am Coll Cardiol 2003;41:765–70).
This slide shows the inclusion criteria of both studies. If the patient had an indication for an ICD, they were enrolled into the MIRACLE ICD trial. In both trials it is important to note that the patients could NOT have a standard indication for pacing.
NYHA Class II patients were enrolled into the MIRACLE ICD trial. The data, however, has not yet been reviewed and analyzed.
An InSync ICD implant was attempted in patients who met inclusion and exclusion criteria within 7 working days of their Baseline evaluation.
Randomization was accomplished in blocked groups for each center in order to ensure a 1:1 balance of therapy and control assignments at each participating institution. Randomization/CPX occurred within 7 days of a successful implant.
All patients were required to be on stable HF medication that included an ACE inhibitor and a beta blocker if tolerated.
Implant success for MIRACLE was 92%, MIRACLE ICD was 89% (MIRACLE trial included the Attain LV Model 2187 and Attain CS Model 2188; MIRACLE ICD trial data included Attain LV Model 2187, Attain CS Model 2188, and Attain SD Model 4189. This percentage of success in the MIRACLE ICD trial did NOT include the Attain OTW Model 4193 lead.)
It is thought that the decrease in success rate for the MIRACLE ICD trial is due to the fact that the physicians may not have put forth an equivalent effort to achieve LV lead position because the patient required an ICD implant regardless. (Remember in the MIRACLE trial, if the implant was unsuccessful, the patient did not receive a device.)
Note that the Attain SD Model 4189 lead has not been FDA released.
Patients were randomized for a period of 6 months to:
InSync ICD - control arm with cardiac resynchronization OFF (DDI35), treatment arm with cardiac resynchronization ON (DDD35)
InSync – control arm with cardiac resynchronization OFF (VDI30) ,treatment arm with cardiac resynchronization ON (VDD30)
The heart failure staff was blinded to the randomization schedule and each patient’s randomization assignment throughout the 6-month follow-up visit. The EP staff were unblinded.
Early crossover to ON/CRT was strongly discouraged (8 patients crossed over to ON arm: 4 due to bradycardia and 4 due to worsening HF).
The patients were blinded as to their assignment
All patients were programmed to ON after completion of the 6-month follow-up visit and testing in their randomized mode.
All patients in the MIRACLE ICD trial received an InSync ICD and the ICD was always active.
Combined Results: When a patient has an improvement in QoL score, the number goes down. Note, here, that the CRT group improved significantly over the control group. Therefore, there was a highly significant treatment affect. The graph here reflects the median at baseline and at 6 months.
We expected Control patients to improve as a group. This is true in heart failure drug trials, and one may anticipate that the placebo effect would be magnified with a treatment like cardiac resynchronization that involves a surgical procedure.
The MIRACLE study was designed and implemented to assess whether there was in fact a treatment effect associated with cardiac resynchronization. All patients were implanted. Both control and cardiac resynchronization groups followed the same follow-up protocol.
There is a treatment effect! The magnitude of that effect on the same endpoints was equal to or greater than that seen with ACE Inhibitors, Carvedilol or digitalis. The improvements with cardiac resynchronization in echocardiographic measures and in cardiopulmonary test results, as well as the reported decrease in hospitalization for worsening heart failure, are consistent with the primary endpoint results.
For NYHA functional class, we separate the results from the two trials. The patients in both the MIRACLE and MIRACLE ICD improved their NYHA class significantly compared to the control group. In the MIRACLE trial, 68% of patients improved by one functional class or more vs. 38% of control. In the MIRACLE ICD trial, 64% improved by one functional class or more vs. 50% of control. There was a highly significant treatment effect in both studies.
Combined Results: There was a highly significant treatment effect between the control and the CRT group for patients improving their peak VO2 during exercise. The graph here reflects the median at baseline and at 6 months.
For cardiopulmonary exercise time, the CRT group improved significantly over the control group. The graph here reflects the median at baseline and at 6 months.
The 6-min hall walk data presented here reflects the median at baseline and 6 months.
Focus first on the solid lines indicating the results of the MIRACLE trial. The patients who received cardiac resynchronization(CR) therapy improved significantly over the control patients.
The dashed lines indicate the results of the MIRACLE ICD trial. The patients who received CR therapy did not improve significantly over the control group possibly because these patient’s baseline status was performed prior to having an InSync ICD and the patients knew they were not protected against SCD and this may have limited their exertion. There was a statistical study effect (P &lt;0.001) meaning there was a significant difference in the trials in this measure. Therefore, the data is presented separately.
Baseline for 6-minute hall walk for the patients in the MIRACLE ICD trial was established at the one month status after the InSync ICD was implanted. At 6 months the two lines are starting to diverge as the CRT patients begin experiencing improvements, and the data is approaching statistical significance. The graph here reflects the median at baseline and 6 months.
Results of 1M vs. 6M analysis:
Control median paired difference: 5 meters
CRT median paired difference: 20 meters
Combined Results: These studies were NOT powered for survival, therefore we will not make mortality claims for the InSync and InSync ICD devices. Medtronic is conducting a European study in Europe with the primary end points of Mortality and Morbidity, called CARE-HF. It will enroll 800 patients and is randomized 1:1 to optimal drug therapy only, or optimal drug therapy + biventricular pacing.
The conclusion one can deduce from this graph is that CRT does not appear to worsen survival.
Main purpose: Show concordance of proof from randomized controlled trials that CRT improves quality of life and functional status.
Key messages:
Results from blinded studies that randomized 1,000 NYHA Class III/IV heart failure patients with a wide QRS show that CRT dramatically improves patients’ perceived quality of life and the clinicians’ assessment of functional status.
The so-called placebo effect was expected. These studies were designed to assess whether there was a treatment effect, and all consistently demonstrated a positive effect.
Main purpose: Show concordance of proof from randomized controlled trials that CRT improves exercise capacity.
Key messages:
From the graph on top, 3 of the 4 randomized trials showed that CRT improves this measure of sub-maximal exercise capacity.
All studies showed that CRT improves peak VO2, regarded as a more objective measure of exercise and functional capacity, compared to control.
Additional information:
The authors of the MIRACLE ICD paper make the following comment on the discrepancy in the 6 minute walk test:
“However, the absence of a positive treatment effect on the 6-MW contrasts with these earlier trials, and with the improvements observed in this study with the more objective measurements of peak oxygen consumption and treadmill exercise duration. Whether these discrepancies are due to differences between patient populations, or to the different timing of the 6-MW test (performed before instead of after CRT system implantation) remains uncertain.”
Main purpose: Show that the improvements observed in quality of life and exercise capacity are sustained through 2 years of CRT.
Key messages:
The improvements in exercise capacity and quality of life with CRT compared with pre-implant baseline are sustained for at least a year
Additional information:
This is from a presentation made at AHA 2003. The MIRACLE study program includes the MIRACLE, MIRACLE ICD (Intensive and General phases) and InSync III trials. All of these studies were ended with FDA approval of the specific device under evaluation. The primary reason for the decline in patients is due to the fact that the respective trial ended before the indexed follow-up.
Main purpose: Explain the risks of a CRT system implant to referral clinicians. Based on Medtronic’s MIRACLE study program and on Guidant’s Contak CD trial. Source of complications is abstract presented at NASPE 2003.
Key messages:
Each clinical trial utilized a clinical events review committee to evaluate complications, including defined procedure-related mortality.
Chiefly due to challenging venous anatomy, implants have been unsuccessful in approximately 10% of patients attempted.
Complication rates by category appeared to be reduced with the Medtronic Attain 4193, with an over-the-wire delivery system, used in the InSync III trial.
Coronary sinus dissection or perforation generally were resolved without further complication.
For comparison, the 30-day mortality in the CABG-PATCH and the AVID trials were 5.4% and 2.4% respectively.
Left ventricular lead complications, primarily dislodgements, occurred in 9% of all cases (4% in the InSync II study).
There is a learning curve. Implant times came down with increased center-based experience.
Main purpose: Respond to safety concern that CRT may be an “electronic positive inotrope.”
Key messages:
CRT improves cardiac function and efficiency without increased myocardial oxygen consumption.
Additional information: Graph at left: Comparison of mechanoenergetic responses to LV free wall electrical stimulation vs intravenous dobutamine. Absolute values are shown for dP/dtmax (abscissa) and for heart rate (HR)-adjusted MVO2 index (ordinate). Both sets of studies had similar dP/dtmax baseline and increase because of intervention. However, dobutamine significantly raised MOV2, whereas pacing/stimulation reduced it (P&lt;0.05). Conclusion: unlike inotropes, CRT does not increase myocardial oxygen consumption with improved systolic performance. EF is improved by a more efficient, rather than stronger, contraction.
Graph at right: Acute positron emission tomography study in 8 HF pts with wide QRS. Compared atrial pacing to atrial synchronized biventricular pacing (CRT). Stroke volume index increased without increasing LV oxidative metabolism with CRT.
Main purpose: Address safety concern that CRT is pro-arrhythmic
Key messages:
No difference between CRT and no CRT in the number of patients with VT/VF events
Additional information:
These data come from a meta-analysis of CRT. The two studies combined assessed CRT in patients with a pre-existing indication fro an ICD. VT/VF events are collected in the devices’ (InSync ICD, Contak CD) diagnostics.
Adult, moderate to severe systolic heart failure patients with evidence of ventricular dysynchrony. Stable heart failure medical regimen was required. If on a Beta Blocker, a therapeutic dose for 3-months prior to enrollment was necessary.
Patients with an existing indication for a pacemaker or an ICD are excluded. Other exclusion criteria include:
Baseline 6 minute walk distance 450 meters
Unstable angina, acute MI, coronary artery revascularization/coronary angioplasty within last 3 months
Chronic atrial arrhythmias, cardioversion from arrhythmia within previous month, paroxysmal atrial arrhythmia within previous month
Supine systolic blood pressure &lt; 80 mm Hg or &gt; 170 mm Hg
Supine resting rate &gt; 140 bpm
Cerebral vascular event with previous 3 months
Cardiac alloograph (patients on heart transplant list not excluded)
Serum creatine &gt; 3.0 mg/dL
Serum hepatic function 3 times upper limit of normal
Primary severe uncorrected valvular disease
Enrollment in concurrent study that may confound results
When the trial started, FDA wanted Peak V02 as primary endpoint. The investigators felt that echo parameters and composite response would be the best parameters of disease progression.
Backup Only:
7 pts did not maintain treatment assignment 4 due to brady indication, 3 due to worsening HF, data included based on intention to treat principle
There were 9 pts who did not have their 6 mo follow up data in the database as of the the database closure date :
5 of 9 Medtronic received follow up form after PMA update data cutoff
1 of 9 died but from had not yet been received
3 of 9 status unknown at time of PMA Update
Overall study visit compliance is 98% (2247 due, 2203 completed)
27 of 579 enrolled met inclusion/exclusion criteria (97%)
VE/VC02 is the metabolic stress test evaluation. It is a better predictor of improvement. It is the respiratory rate divided by the CO2. The higher the number, the worst the situation.
Class II at baseline had a mean 6 MHW of 370 meters whereas the Class III and IV patients had a mean baseline 6 MHW of approx. 200 meters.
63% of the CRT showed improvement at 6-months compared to 38% of the Control patients. The difference is statistically significant using a Chi-square test.
Main purpose: Show that a large number of patients have been studied in completed and ongoing randomized controlled studies of CRT. Use in conjunction with previous slide.
Key messages:
Over 3000 patients have been enrolled in randomized controlled clinical trials presented to date.
When CARE-HF, another landmark trial assessing mortality and hospitalization, is reported, close to 4,000 patients will have been studied.
Main purpose: Set up discussion for next slide.
Key messages:
Despite the significant contributions of ACE inhibitors and beta blockers to help heart failure patients live longer, the annual mortality of heart failure patients remains high.
As previously shown, moderate to severe heart failure patients with a wide QRS are at higher risk.
Cardiac resynchronization and ICD therapies can help this higher risk group live longer
Additional information:
SOLVD-T was a landmark trial reported in 1991 that showed ACE inhibitors reduced mortality in symptomatic heart failure patients. The MERIT-HF (metroprolol study in Europe and North America) and the CIBIS II (bucindilol in Europe) studies reported in 1999, demonstrated that the addition of beta blockade to conventional treatment, including ACE-inhibitors, further improved survival. The results from these trials are consistent with those reported from the US cardvedilol trial.
As reported in the same review paper, if one extracts NYHA III/IV patients from the combined CIBIS II, MERIT-HF and US carvedilol trials, 1- year mortality in the control and treatment groups are 15.15 and 9.5% respectively.
Main purpose: Illustrate improvements in mortality and hospitalization with CRT and CRT + ICD on top of optimal medical therapy
Key messages:
Neither MIRACLE, nor MIRACLE ICD, nor Contak CD were powered to detect differences in mortality or hospitalizations.
Additional information:
Reprints of MIRACLE: UC200200338EN
Reprints of JAMA meta-analysis: UC200303498 EN
It is very important that a patient set his/her own goals to therapy that are realistic.
It is very important that a patient set his/her own goals to therapy that are realistic.
Main purpose: Respond to concern that CRT/CRT + ICD is too expensive.
Key messages:
Like cardiac resynchronization therapy, a variety of medical procedures exist to help improve patients’ quality of life, clinical status, and survival. Many of these procedures –and their associated costs – are accepted as standard of care.
Total annual expenditures for CRT and CRT+ICD remain relatively minor when compared with other standards of care.
CRT and CRT+ICD devices last 4 to 6 years
Additional information:
US data only. Data sources:
All except dialysis: Weighted DRG payment for 2003 using the number of discharges in 2000: HCUPnet, Healthcare Cost and Utilization Project. Agency for Healthcare Research and Quality, Rockville, MD. http://www.ahrq.gov/data/hcup/hcupnet.htm.
Dialysis: Medicare 2000 payment per patient: The United States Renal Data System (USRDS), 2002. www.usrds.org
+This cost comparison is meant for illustrative purposes only; it is not intended as a therapeutic comparison.
References:
Hunnicutt D, Smith A, Leon AR, Langberg JL. Experience with CRT in patients requiring inotropic support. Accepted for presentation at: North American Society of Pacing and Electrophysiology 24th Annual Scientific Sessions; May 14-17, 2003; Washington, DC.
DeLurgio DB, Chinchoy E, Ransom SA, et al. Stability of the optimal right ventricular to left ventricular timing sequence during biventricular pacing for congestive heart failure as determined by Doppler-derived stroke volume. Presented at: North American Society of Pacing and Electrophysiology 23rd Annual Scientific Sessions; May 8-11, 2002; San Diego, CA.
Moss AJ, Zareba W, Hall J, et al for the Multicenter Automatic Defibrillator Implantation Trial II Investigators. Prophylactic implantation of a defibrillator in patients with myocardial infarction and reduced ejection fraction.N Engl J Med 2002;346:877-883.
So we naturally headed towards an endocardial approach. Nowdays Using coronary venous system we try to reach the best pacing site on the base of Auricchio’s work in 1998.
Bakker P, Meijburg H, de Jonge N, van Mechelen R, Wittkampf F, Mower M, Thomas A. Beneficial effects of biventricular pacing in congestive heart failure. PACE 1994;17:820 (abstract 318). CPI study of 5 NYHA Class III/IV pts with DCM, complete LBBB and prolonged PR interval. DDD pacemaker implanted with endocardial RV lead and epicardial LV lead. LV capture lost in 1 pt at 3 months, who had improved initially. 4 pts improved at least 1 NYHA Class at 3 months.
Cazeau S, Ritter Ph, Lazarus A, Gras D, Backdach H, Mundler O, Mugica J. Multisite pacing for end-stage heart failure: early experience. PACE 1996;19[II]:1748-1757. Initial experience on 8 pts with wide QRS (mean 200 35 ms) and end-stage HF (NYHA Class IV) with biventricular pacing including 5 pts with transvenous LV system.
Daubert JC, Ritter Ph, Gras D, Pavin D, Cazeau S, Mabo Ph. Use of specifically designed coronary sinus leads for permanent left ventricular pacing: preliminary experience. PACE 1997; 20[II]:? (NASPE abstract 17). 15 pts, mean follow-up 6 months (2-10) with either model 2188 or custom 2879 (2188 with different bend) implanted in the LV. Successful implant in 11 pts (73%). 1.3±0.7 V pacing threshold acutely vs. 1.9±1.0 V threshold chronically. No lead dislodgment or other lead-related complication was observed. “In conclusion, this preliminary experience is encouraging in terms of feasibility, safety and long term results. Further improvement in lead configuration is needed to increase implantation success rate.”
Gras D, Mabo Ph, Tscheliessnigg KH, Pedersen AK, Tang T. Early results regarding implant procedures of a new biventricular atrial synchronized pacing system. PACE 1998; 21[II]:824 (NASPE Abstract). 18 DCM pts. 16 successful implants (89%), 14 in lateral vein, 2 in GCV. Total procedure duration: 101 35 min. Fluoroscopic time: 24 12 min.
Lurie K, , Benditt D, Samiah N, Blanc JJ. A transvenous “Long Guiding Sheath” technique for permanent left ventricular pacing lead implantation in patients with heart failure. Circulation 1998; 98[17]: I-841 (abstract 4414). Report on use of a 45 cm radiopaque peel away introducer sheath by Daig for LV lead placement. The steps: 1) sheath is placed in SVC as introducer; 2) EP catheter (Daig CSL) is put through the sheath and introduced into the CS; 3) A venogram is obtained using the EP catheter; 4) sheath is advanced over the EP catheter into the CS; 5) EP catheter is removed; 6) LV lead (std RV leads used) is placed through the sheath into the CS. 80% success rate with no complications in 20 pts.
Main purpose: Demonstrate evidence of left ventricular reverse remodeling.
Key messages:
Following 3 months of chronic cardiac resynchronization, LV volumes return slowly to baseline, pre-implant levels after the device is turned off indicating reverse remodeling.
On the other hand, mitral regurgitation increases acutely, a finding corroborated by Breithardt and colleagues (J Am Coll Cardiol 2003;41:765–70).
Key Points: (Note – a subset of the 453 patients provide the paired data)
Measures of both cardiac function and cardiac structure showed improvement with cardiac resynchronization.
A 4.6 percentage point improvement in LVEF within the CRT group of patients contrasted significantly with a reduction of 0.2 percentage points in the Control group.
Likewise, patients receiving CRT showed a reduction in mitral regurgitation (-2.7 cm2)that was statistically significantly greater than the modest improvement (-0.5 cm2) observed within the Control group of patients.
The reduction in left ventricular end diastolic diameter of 3.5 mm for CRT patients was significant compared with no change on average for Control group patients.
Other Information:
Echocardiographic results are from a single observer at a core laboratory (University of Pennsylvania).
All data are paired; data for the same patients are shown for each time point.
While ventricular pacing spikes were often observed on the simultaneously recorded ECG, each echo study was blinded with regard to identity and analyzed individually and without reference to echocardiographic images or knowledge of measurements from other studies of the same patient.
Key Points: (Note – a subset of the 453 patients provide the paired data)
Peak VO2 had virtually no change in the Control group of patients compared with a 1.1 ml/kg/min improvement for CRT group patients. The treatment effect was statistically significant.
Total exercise time during the cardiopulmonary exercise test showed similar results. A modest average improvement by Control group patients was overshadowed by an increase of over 1 minute by the patients receiving CRT.
Other Information:
Cardiopulmonary exercise results were assessed by a core laboratory (University of Cincinnati).
All data are paired; data for the same patients are shown for each time point.
The MIRACLE study was not powered to study mortality. However, you can conclude from the results here that cardiac resynchronization does not worsen survival.
Combined Results: These studies were NOT powered for survival, therefore we will not make mortality claims for the InSync and InSync ICD devices. Medtronic is conducting a European study in Europe with the primary end points of Mortality and Morbidity, called CARE-HF. It will enroll 800 patients and is randomized 1:1 to optimal drug therapy only, or optimal drug therapy + biventricular pacing.
The conclusion one can deduce from this graph is that CRT does not appear to worsen survival.
Main purpose: Show concordance of proof from randomized controlled trials that CRT improves quality of life and functional status.
Key messages:
Results from blinded studies that randomized 1,000 NYHA Class III/IV heart failure patients with a wide QRS show that CRT dramatically improves patients’ perceived quality of life and the clinicians’ assessment of functional status.
The so-called placebo effect was expected. These studies were designed to assess whether there was a treatment effect, and all consistently demonstrated a positive effect.
Main purpose: Show concordance of proof from randomized controlled trials that CRT improves exercise capacity.
Key messages:
From the graph on top, 3 of the 4 randomized trials showed that CRT improves this measure of sub-maximal exercise capacity.
All studies showed that CRT improves peak VO2, regarded as a more objective measure of exercise and functional capacity, compared to control.
Additional information:
The authors of the MIRACLE ICD paper make the following comment on the discrepancy in the 6 minute walk test:
“However, the absence of a positive treatment effect on the 6-MW contrasts with these earlier trials, and with the improvements observed in this study with the more objective measurements of peak oxygen consumption and treadmill exercise duration. Whether these discrepancies are due to differences between patient populations, or to the different timing of the 6-MW test (performed before instead of after CRT system implantation) remains uncertain.”
Main purpose: Illustrate improvements in mortality and hospitalization with CRT and CRT + ICD on top of optimal medical therapy
Key messages:
Neither MIRACLE, nor MIRACLE ICD, nor Contak CD were powered to detect differences in mortality or hospitalizations.
Additional information:
Reprints of MIRACLE: UC200200338EN
Reprints of JAMA meta-analysis: UC200303498 EN
Main purpose: Respond to safety concern that CRT may be an “electronic positive inotrope.”
Key messages:
CRT improves cardiac function and efficiency without increased myocardial oxygen consumption.
Additional information: Graph at left: Comparison of mechanoenergetic responses to LV free wall electrical stimulation vs intravenous dobutamine. Absolute values are shown for dP/dtmax (abscissa) and for heart rate (HR)-adjusted MVO2 index (ordinate). Both sets of studies had similar dP/dtmax baseline and increase because of intervention. However, dobutamine significantly raised MOV2, whereas pacing/stimulation reduced it (P&lt;0.05). Conclusion: unlike inotropes, CRT does not increase myocardial oxygen consumption with improved systolic performance. EF is improved by a more efficient, rather than stronger, contraction.
Graph at right: Acute positron emission tomography study in 8 HF pts with wide QRS. Compared atrial pacing to atrial synchronized biventricular pacing (CRT). Stroke volume index increased without increasing LV oxidative metabolism with CRT.
Main purpose: Address safety concern that CRT is pro-arrhythmic
Key messages:
No difference between CRT and no CRT in the number of patients with VT/VF events
Additional information:
These data come from a meta-analysis of CRT. The two studies combined assessed CRT in patients with a pre-existing indication fro an ICD. VT/VF events are collected in the devices’ (InSync ICD, Contak CD) diagnostics.
Backup Only:
7 pts did not maintain treatment assignment 4 due to brady indication, 3 due to worsening HF, data included based on intention to treat principle
There were 9 pts who did not have their 6 mo follow up data in the database as of the the database closure date :
5 of 9 Medtronic received follow up form after PMA update data cutoff
1 of 9 died but from had not yet been received
3 of 9 status unknown at time of PMA Update
Overall study visit compliance is 98% (2247 due, 2203 completed)
27 of 579 enrolled met inclusion/exclusion criteria (97%)
Main purpose: Explain the risks of a CRT system implant to referral clinicians. Based on Medtronic’s MIRACLE study program and on Guidant’s Contak CD trial. Source of complications is abstract presented at NASPE 2003.
Key messages:
Each clinical trial utilized a clinical events review committee to evaluate complications, including defined procedure-related mortality.
Chiefly due to challenging venous anatomy, implants have been unsuccessful in approximately 10% of patients attempted.
Complication rates by category appeared to be reduced with the Medtronic Attain 4193, with an over-the-wire delivery system, used in the InSync III trial.
Coronary sinus dissection or perforation generally were resolved without further complication.
For comparison, the 30-day mortality in the CABG-PATCH and the AVID trials were 5.4% and 2.4% respectively.
Left ventricular lead complications, primarily dislodgements, occurred in 9% of all cases (4% in the InSync II study).
There is a learning curve. Implant times came down with increased center-based experience.
Main purpose: Show that a large number of patients have been studied in completed and ongoing randomized controlled studies of CRT. Use in conjunction with previous slide.
Key messages:
Over 3000 patients have been enrolled in randomized controlled clinical trials presented to date.
When CARE-HF, another landmark trial assessing mortality and hospitalization, is reported, close to 4,000 patients will have been studied.
Main purpose: Respond to concern that CRT/CRT + ICD is too expensive.
Key messages:
Like cardiac resynchronization therapy, a variety of medical procedures exist to help improve patients’ quality of life, clinical status, and survival. Many of these procedures –and their associated costs – are accepted as standard of care.
Total annual expenditures for CRT and CRT+ICD remain relatively minor when compared with other standards of care.
CRT and CRT+ICD devices last 4 to 6 years
Additional information:
US data only. Data sources:
All except dialysis: Weighted DRG payment for 2003 using the number of discharges in 2000: HCUPnet, Healthcare Cost and Utilization Project. Agency for Healthcare Research and Quality, Rockville, MD. http://www.ahrq.gov/data/hcup/hcupnet.htm.
Dialysis: Medicare 2000 payment per patient: The United States Renal Data System (USRDS), 2002. www.usrds.org
+This cost comparison is meant for illustrative purposes only; it is not intended as a therapeutic comparison.
Main purpose: Set up discussion for next slide.
Key messages:
Despite the significant contributions of ACE inhibitors and beta blockers to help heart failure patients live longer, the annual mortality of heart failure patients remains high.
As previously shown, moderate to severe heart failure patients with a wide QRS are at higher risk.
Cardiac resynchronization and ICD therapies can help this higher risk group live longer
Additional information:
SOLVD-T was a landmark trial reported in 1991 that showed ACE inhibitors reduced mortality in symptomatic heart failure patients. The MERIT-HF (metroprolol study in Europe and North America) and the CIBIS II (bucindilol in Europe) studies reported in 1999, demonstrated that the addition of beta blockade to conventional treatment, including ACE-inhibitors, further improved survival. The results from these trials are consistent with those reported from the US cardvedilol trial.
As reported in the same review paper, if one extracts NYHA III/IV patients from the combined CIBIS II, MERIT-HF and US carvedilol trials, 1- year mortality in the control and treatment groups are 15.15 and 9.5% respectively.
It is very important that a patient set his/her own goals to therapy that are realistic.