Today, in addition to measurement of left ventricular ejection fraction, the simple 12-lead surface ECG remains the only evidence-based means of identifying patients who may obtain the substantial benefits of CRT

1. OPTIMIZING CARDIAC
RESYNCHRONIZATION
THERAPY FOR
CONGESTIVE HEART FAILURE
Only for systolic heart failure
Dr Ramachandra
ECG — Still the Best for Selecting Patients for CRT
Clyde W. Yancy, M.D., and John J.V. McMurray, M.D.

2. CRT APPEARS DEADLY IN SHORT-QRS
PATIENTS

3. CRT FOR NARROW QRS WITH LV
SYSTOLIC DYSFUNCTION
 "This is the final nail in the coffin for CRT in
patients with only slightly-prolonged QRS,"
commented Dr. Douglas P. Zipes, a professor
and electrophysiologist at Indiana University
in Indianapolis.

4. PERSPECTIVE
 Advanced systolic heart failure
 Mechanical dyssynchrony positive
 CRT-P/D effective
 improving symptoms and reducing mortality.
 several recognized approaches to optimize
 Imaging modalities can assist with identifying the
myocardium with the latest mechanical activation
for
targeted left ventricular lead implantation.
 Device programming can be tailored to maximize
biventricular
pacing, and thereby is its benefit.
 Cardiac imaging has shown that atrioventricular
and interventricular intervals can be adjusted to
further reduce dyssynchrony.

5. ELECTRO/MECHANICAL
DYSCHRONY IN ADVANCE
SYSTOLIC HEART FAILURE.
Electrical dyschrony(12-ECG) Mechanical
dyschrony(Echocardiogragh)
1D-AV block=AV delay E ,A not keep harmony ,also with
R of ECG
LBBB=VV conduction delay only
in 25% of patients with systolic
dysfunction have QRS duration
that exceeds 120 ms
Paradoxical IVS

6. MONITORING IMPROVEMENT
 ECG-electrical dyssynchrony improvement
 ECHO-mechanical dyssynchrony improvement
 NYHA CLASS
 6-Minute walk
 Quality-of-life score
 Duration of survival
70-80% response to
CRT

7. LEAD LOCATION FOR CRT
OPTIMIZATION
 Positioning the LV lead outside the site of latest
mechanical activation may be associated with
suboptimal response to CRT and worse long-term
outcome
 left side of the chest is preferred for 2 reasons
1. LSCV-continuous route to access the CS, Rt-
challenging/ angulated
2.Defibrillation threshold is less on left
 Leads placed in the RA/RV/lateral wall of the LV
through the coronary sinus

8. LEAD LOCATION....CONTD
 RV lead first, as baseline LBBB at risk
 LV lead next, is challenging one
 RA lead is last(even in Afib)
 RV lead-no preferential location
 LV lead-lateral/posterior-lateral wall of the LV
via CS/epicardial= goal of pacing from the most
mechanically delayed portion on the LV

9. ECHO ASSESSMENT OF
DYSSYNCHRONY AND CRT
RESPONSE
 Echocardiography parameters can predict/decide
which patient need CRT but helps in monitoring
the patients with CRT
 SPWMD >130msec is a very good
forecaster(Pitzalis MV)
 CONTACT-CD denies role of SPWMD
 PROSPECTUS-Tissue Doppler is usuful.

10. DEVICE PROGRAMMING TO
OPTIMIZE TIMING
 Most studies point to a benefit in adjusting the
AV and VV timing.
 Variability on the best approach to make these
adjustments
 how often it should be done?

11. AV OPTIMIZATION
 AV optimization is must after CRT device implant,
particularly
if the post-CRT implant Doppler echo of the mitral inflow
suggests
suboptimal diastolic filling patterns
 Long A-V interval, Doppler echo will display fused E and A
waves with evidence of mitral regurgitation during diastole.
Additionally, a prolonged AV delay allows the ventricle to
initiate its own beat before receiving a pacing impulse
 Short AV interval have a truncated A wave resulting in a loss
of the atrial kick, resulting in reduced contribution from the
atria and reduced ventricular filling time
 Optimal AV timing can be identified with aortic systole that
begins at the end of A
 Aortic velocity time integral (VTI), which is a surrogate for
cardiac output, can be used for AV optimization. The optimal
AV delay is determined by adjusting the AV delay until the
largest aortic VTI is achieved.

12. SIMPLIFIED AV DELAY SCREENING
USING MITRAL INFLOW DOPPLER
VELOCITIES

13. OPTIMIZING AV DELAY USING VTI

14. VV OPTIMIZATION
 2D ECHO:A delayed interval of 40-50 ms has
been accepted as being indicative of VV
dyssynchrony. MIRACLE
trial, the measurement of VV mechanical delay
was reduced by approximately 19% after CRT.Yu
et al reported normalization in dyssynchrony in
patients who previously had significant
mechanical delay in the lateral wall of the LV
and RV
 3D ECHO
 Dp/dt(echo)
 Exercise benefit

15. INTERVENTRICULAR
OPTIMIZATION USING AORTIC
VELOCITY TIME INTEGRAL (VTI).

16. HOW OFTEN TO OPTIMIZE CRT
DEVICES?
 Optimal follow-up/long-term programming for
CRT devices is uncertain
 Frequent monitoring/adjustment to maintain
optimal AV and VV timings
 FREEDOM -will determine whether frequent
optimization of CRT ,using a new device-based
algorithm, is associated with better clinical
outcomes than current standard of care

17. TAKE HOME
 CRT address systolic heart failure
 Rectify mechanical dyssynchrony
 improving symptoms and reducing mortality.
 There are now several recognized approaches to
optimize CRT.
 Imaging modalities can assist with identifying the
myocardium with latest mechanical activation for
targeted LV lead implantation.
 Device programming can be tailored to maximize
biventricular pacing and thereby its benefit.
 Cardiac imaging has shown that AV and VV
intervals can be adjusted to further reduce
dyssynchrony. Optimization of CRT devices continues
to be an area of active research

18. A RARE MOST BEAUTY AND
FRAGRANCE ON THIS EARTH
“BRAMAKAMAL