OPTIMIZING CARDIACRESYNCHRONIZATION THERAPY FORCONGESTIVE HEART FAILUREOnly for systolic heart failure

Dr Ramachandra

ECG — Still the Best for Selecting Patients for CRTClyde W. Yancy, M.D., and John J.V. McMurray, M.D.

CRT APPEARS DEADLY IN SHORT-QRS PATIENTS

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.

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.

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

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

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

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

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.

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?

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.

SIMPLIFIED AV DELAY SCREENING USING MITRAL INFLOW DOPPLER VELOCITIES

OPTIMIZING AV DELAY USING VTI

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

INTERVENTRICULAR OPTIMIZATION USING AORTIC VELOCITY TIME INTEGRAL (VTI).

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

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

A RARE MOST BEAUTY AND FRAGRANCE ON THIS EARTH “BRAMAKAMAL