3. First External Stimulation
Catharina Serafin
Increase in heart rate (140 bpm)
Hugo von Ziemssen (1882)
Stimulation: ON OFF
Right Ventricle
Left Ventricle
4. 1827/46 Bradycardia as cause of syncope
(Adams, Stokes)
1882 First external stimulation (von Ziemssen)
1932 First external pacemaker (Hyman)
1952 External stimulation via surface electrodes
(Zoll)
1958 External stimulator with transvenous lead
(Furman, Robinson)
1958 First implantable PM with transvenous lead
(Elmquist, Senning)
Historical Milestones
5. First External Pacemaker
Hyman (1932)
- Clockwork generator with manual power
- Transthoracic stimulation needle
- Handle turn to provide induction stimulus
Cardiac standstill
Stimulation 120 ppm
8. First Implantable Pacemaker
Senning and Elmquist (1958)
Rune Elmquist
Engineer at Siemens-Elema
Ake Senning, Cardiac Surgeon
Karolinska Hospital Stockholm
13. Founded in 1949 as a
medical equipment
service company
History and Background History
• First external wearable
pacemaker
14. Success With Implantable Pacemakers
In the United States, the first successful attempts at designing a totally implantable
pacemaker were reported by Drs. William Chardack and Andrew Gage at the Veterans
Administration Hospital in Buffalo, New York, and Wilson Greatbatch, an electrical
engineer. The three men carried out more than two years of experimental work and
testing, then published a paper about their work in 1960.
Medtronic's founders read the article with interest and soon contacted the New York
researchers. Palmer Hermundslie flew his own plane to Buffalo to meet Dr. Chardack and
Greatbatch, and signed a contract giving Medtronic exclusive rights to produce and
market the Chardack-Greatbatch implantable pulse generator. Within two months of
beginning production in late 1960, Medtronic had received orders for 50 of the $375
implantable units.
Co-founder Palmer Hermundslie often piloted his own plane to make emergency
deliveries of pacemakers.
At the same time, Medtronic appointed Picker International Corporation of White
Plains, New York, as its sole distributor outside the United States, exclusive of Canada.
Picker's 72 foreign sales offices greatly expanded the marketing efforts of Medtronic,
which had 14 sales representatives covering the United States and Canada.
In addition to the implantable pacemaker, the representatives sold seven other
Medtronic products, including the Telecor, which visibly and audibly monitored heart
activity; the Cardiac Sentinel, an automatic alarm that summoned aid when the patient's
heart activity became critical and stimulated the heart with an electronically regulated
pulse; and a Coagulation Generator, used to control bleeding during surgery without
damaging nearby tissue.
Dr. C. Walton Lillehei with a child who received
one of the early Medtronic external pacemakers
16. Implantable Electronic Cardiac Devices
Historical Aspects
1932 1958 1964 1970 1980’s 1994
Hyman
Senning and
Elmquist
1st implant of
an electronic
PM
Mirowski
Development
of the 1st ICD –
implant in dogs
1st report of
CRT
RECENTLY
Furman
1st endocardiac
PM
Heart Failure
control
Home
Monitoring
17. Basic Concept of Pacemaker
Over view
- Pacemaker System
- Pacemaker Function
- NBG Code
- Lead Impedance
- The magnet Mode & Electromagnetic Interference
- Information for patient ‘s pacemaker
18. What is a pacemaker ?
A device for increaseing a slow HR
A device used primarily to correct some types of
bradycardia, or slow heart rhythms.
19. Who need it ?
Indications for Pacing
Sick Sinus Syndrome
Heart Block
Post RF Ablation
20. How does it work ?
Attach the pacemaker system
Pulse generator
Sensing and Pacing leads
Make it into a circuit
Put the system into the body / under the skin and join to the
heart by pacing wire
Program it’s function by the programmer
26. Lead System
A lead is the insulated wire used to connect the pulse
generator to the cardiac tissue
The lead transmits the energy to the myocardium and
relays intrinsic cardiac signals back to the sensing
circuit
27. Components of a Pacing Lead
Connector
Proximal Ring
Electrode
Lead
Body
Active Fixation
Mechanism
Suture
Sleeve
Distal Tip
Electrode
40. Atrial Lead Placement
The atrial lead should be implanted on the septal wall
of the atrial appendage
Once the lead is in the proper position it will have a
“wagging” appearance
46. How to stimulate?
Ohm´s Law: V = R x I
R =
V
I
Voltage
Current
= =
[V]
[A]
The higher the voltage and the lower the resulting current
the higher is the resistance.
V = Voltage, I = Current , R = Resistance
58. How to stimulate?
E = R x I x t
E = x t (Joule)
V2
R
Energy
V = R x I
V
R
I =
E = V x x tV
R
59. How to stimulate?
E = x t (J)
V2
R
Energy
How to save energy?
- lower pulse amplitude (V²)
- lower pulse duration
- high impedance
60. Strength Duration Curve
pulse width (msec)
Voltagethreshold(V)
Chronaxie
Rheobase
2 x Rheobase
Most efficient pulse width
• The rheobase is the least voltage needed to
depolarise the heart at an infinite pulse duration.
• The chronaxie is the shortest pulse duration
required to depolarise the heart at a voltage twice
the rheobase.
61. Pacing Thresholds
Suggested Intraoperative Values
Atrium
Less than 1.5 Volts
Ventricular
Less than 1.0 Volts
Pacing Impedance
300-1500 Ω Depending on lead type
62. Acute To Chronic Threshold Change
Historically reported to occur between
2-8 weeks post implant
Thresholds may increase 2-5 times
Virtual Electrode - Myocardial Interface
67. Sensing
Sensing Threshold: indicates the minimum
intracardiac signal that will be sensed by the
pacemaker to initiate the pacemaker response
(inhibited or triggered)
Sensing
73. The NASPE/BPEG Generic (NBG) Code
Position
Category
Letters
Used
Manufac-
turer’s
Designation
Only
I II III
Chamber(s)
Paced
Chamber(s)
Sensed
Response
to Sensing
Rate modulation Multisite
pacing
O-None
P-Simple
Programmable
M-Multi-
Programmable
C-Communicating
R-Rate
modulation
O-None
A-Atrium
V-Ventricle
D-Dual
(A+V)
S- Single
(A or V)
S- Single
(A or V)
O-None
A-Atrium
V-Ventricle
D-Dual
(A+V)
O-None
T-Triggered
I-Inhibited
D-Dual
(T+I)
O-None
A-Atrium
V-Ventricle
D-Dual
(A+V)
IV V
Version 2001
74. Insulation Break
Current is escaping
Decreased Resistance
Increased Current Drain
Pacing and sensing problems
75. Lead Fracture
Current cannot reach heart
Increased Resistance
Decreased Current Drain
Pacing and sensing problems
82. Lead Resistance/Impedance
Changes
High Resistance
> 2500 ohms
Also called an “Open Circuit”
Chronic lead system
Fractured lead conductor coil
Acute lead system
Loss of contact between the terminal pin of the lead and the
pacemaker header set screw
83. Low Resistance
< 250 ohms
Also called “Shorted Circuit”
Insulation Break-Down
Insulation cut by suture
Degradation of the insulation
Subclavian Crush Syndrome
Lead Resistance/Impedance
Changes
86. 1st documented termination of VF with elevated current
Their work went largely unnoticed for 30 years
ICD Evolution: 1899
87. • Reproduced electric current
termination of VF
• Done at the request of Bell
telephone to address
electrocution of line workers
(occurring at the rate of 1000/yr)
ICD Evolution: 1930
William Kouwenhoven (1886-1975)
88. What is ICD Therapy?
• ICD therapy consists of
pacing, cardioversion, and
defibrillation therapies to
treat tachyarrhythmias. ICDs
also have programmable
diagnostic functions.
• An ICD system includes the
device, and the pacing,
sensing and defibrillation
lead(s).
91. 1970
• Patent granted for
first totally
implantable
defibrillator
• System used an
intracardiac catheter
and SQ patch with
detection via RV
pressure transducer
ICD Evolution
Michael Mirowski (1924-1990)
97. Ventricular Dysynchrony and Cardiac
Resynchronization
• Ventricular Dysynchrony1
– Electrical: Inter- or
Intraventricular conduction delays typically manifested as left bundle
branch block
– Structural: disruption of myocardial collagen matrix impairing electrical
conduction and mechanical efficiency
– Mechanical: Regional wall motion abnormalities with increased workload
and stress—compromising ventricular mechanics
• Cardiac Resynchronization
– Therapeutic intent of atrial synchronized biventricular pacing
• Modification of interventricular, intraventricular, and atrial-ventricular
activation sequences in patients with ventricular dysynchrony
• Complement to optimal medical therapy
1 Tavazzi L. Eur Heart J 2000;21:1211-1214
98. Prevalence of Inter- or Intraventricular
Conduction Delay
1 Havranek E, Masoudi F, Westfall K, et al. Am Heart J 2002;143:412-417
2 Shenkman H, McKinnon J, Khandelwal A, et al. Circulation 2000;102(18 Suppl II): abstract 2293
3 Schoeller R, Andersen D, Buttner P, et al. Am J Cardiol. 1993;71:720-726
4 Aaronson K, Schwartz J, Chen T, et al. Circulation 1997;95:2660-2667
5 Farwell D, Patel N, Hall A, et al. Eur Heart J 2000;21:1246-1250
IVCD 15%
IVCD >30%
General HF Population1,2
Moderate to Severe
HF Population3,4,5
99. 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
Wide QRS – Proportional Mortality Increase
• NYHA Class II-IV patients
• 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
1 Gottipaty V, Krelis S, Lu F, et al. JACC 1999;33(2) :145 [Abstr847-4].
Vesnarinone Study1
(VEST study analysis)
100. Clinical Consequences of
Ventricular Dysynchrony
• Abnormal
interventricular
septal wall motion1
• Reduced dP/dt3,4
• Reduced pulse
pressure4
• Reduced EF and
CO4
• Reduced diastolic
filling time1,2,4
• Prolonged MR
duration1,2,4
1 Grines CL, Bashore TM, Boudoulas H, et al. Circulation 1989;79:845-853.
2 Xiao, HB, Lee CH, Gibson DG. Br Heart J 1991;66:443-447.
3 Xiao HB, Brecker SJD, Gibson DG. Br Heart J 1992;68:403-407.
4 Yu C-M, Chau E, Sanderson JE, et al. Circulation. 2002;105:438-445.
Click to Start/Stop
101. Longer
Shorter
Relaxed
Courtesy of Dr Kass, MD, Johns Hopkins University, Maryland.
SEPTUM
BASE
APEX
SEPTUM
BASE
Normal Dilated Cardiomyopathy
APEX
Left Ventricular Dysfunction
Electromechanical Dyssynchrony
102. Summary of Proposed Mechanisms
Yu C-M, Chau E, Sanderson J, et al. Circulation 2002;105:438-445
Intraventricular
Synchrony
Atrioventricular
Synchrony
Interventricular
Synchrony
LA
Pressure
LV Diastolic
Filling
RV Stroke
Volume
LVESV LVEDV
Reverse Remodeling
Cardiac Resynchronization
MR dP/dt, EF, CO
( Pulse Pressure)
103. Proposed Mechanisms: Improved
Intraventricular Synchrony
Kass D Chen-Huan C, Curry C, et al. Circulation 1999;99:1567-73
PV loop tracings at right illustrate BiV/LV
pacing produces: greater stroke work
(area) and increased stroke volume
(width), and a reduced systolic volume
0
40
80
120
0 100 200 300
0
40
80
120
0 100 200 300
0
40
80
120
0 100 200 300
0
40
80
120
0 100 200 300
LVPressure(mmHg)LVPressure(mmHg)
LV Volume (mL) LV Volume (mL)
RV Apex RV Septum
LV Free Wall Biventricular
----- NSR Control - - - VDD Pacing
Adapted from Kass et al.
104. Proposed Mechanisms: Improved
Intraventricular Synchrony
Click to Start/Stop
dP/dt 1,3,4 EF1,5
Pulse Pressure 3,4 SV&CO1, 2
Improved Intraventricular
Synchrony1,2
MR1
LVESV1 LA
Pressure1
1 Yu C-M, Chau E, Sanderson J, et al. Circulation 2002;105:438-445
2 Søgaard P, Kim W, Jensen H, et al. Cardiology 2001;95:173-182
3 Kass D Chen-Huan C, Curry C, et al. Circulation 1999;99:1567-73
4 Auricchio A, Ding J, Spinelli J, et al. J Am Coll Cardiol 2002;39:1163-1169
5 Stellbrink C, Breithardt O, Franke A, et al. J Am Coll Cardiol 2001;38:1957- 65
105. Proposed Mechanisms: Improved
Atrioventricular Synchrony
Click to Start/Stop
1 Yu C-M, Chau E, Sanderson J, et al. Circulation 2002;105:438-445
2 Kindermann M, Frohlig G, Doerr T, et al. Pacing Clin Electrophysiol 1997; 20(I):2453-2462
3 Breithardt O, Stellbrink C, Franke A, et al. Am Heart J 2002;143:34-44
4 Søgaard P, Kim W, Jensen H, et al. Cardiology 2001;95:173-182
Improved Atrioventricular
Synchrony
LA1
Pressure
LV Diastolic
Filling1,3
LVEDV1,4
Optimized AV Delay:
Isovolumic Contraction Time1,2
MR1,4
106. 1 Yu C-M, Chau E, Sanderson J, et al. Circulation 2002;105:438-445
2 Kerwin W, Botvinick E, O’Connel W, et al. JACC 2000;35:1221-7
Improved Interventricular
Synchrony1,2
LV Diastolic
Filling1
RV Stroke
Volume1
Courtesy of Ottawa Heart Institute
LV Wall
Endocardium
RV
Septum
LV
Proposed Mechanisms: Improved
Interventricular Synchrony
107. Achieving Cardiac Resynchronization
Mechanical Goal: Atrial-synchronized bi-ventricular pacing
• Transvenous Approach
– Standard pacing lead in RA
– Standard pacing or defibrillation lead in RV
– Specially designed left heart lead placed in a left ventricular
cardiac vein via the coronary sinus
Right Atrial
Lead
Right Ventricular
Lead
Left Ventricular
Lead
