Abstract 16778: Are Optimal Biventricular Pacemaker Settings Always Optimal for the Right Ventricle in Non Responders to Cardiac Resynchronization Treatment?
Background: 30-35% of patients who undergo cardiac resynchronization treatment (CRT) remain non responders. Optimization of atrioventricular delay (AVD) and interventricular delay (VVD) improves both left ventricular (LV) hemodynamics and CRT non responder rates. We examined whether optimization of AVD and VVD improves right ventriclar (RV) hemodynamics.
Methods: 25 non responder patients to CRT underwent comprehensive echocardiography guided optimization focusing on LV. We also collected concomitant PW Doppler and tissue Doppler data at various AVD and VVD for RV inflow (filling time), RV outflow velocity time integral (VTI) and RV ejection time. We compared simultaneous LV and RV data at various AVD and VVD.
Results: Only 10-28% of patients had comparable optimal AVD and VVD for both LV and RV as evaluated by above parameters (Figure 1). Table 1 shows the effect of optimization of AVD and VVD on LV and RV echo Doppler. Despite significant improvement in LV parameters, none of the Doppler parameters for RV changed significantly. Eight patients had worsening of tricuspid filling time (403±91 vs 339±107 ms, p<0.03) after optimization. There was a trend towards increased RV size in these patients with worsening of RV filling (4.76 ± 0.79 vs. 4.11 ± 0.97 cm, p=0.16) with optimization.
Conclusion: Our results show that improvement in LV hemodynamics is not associated with comparable improvement in RV hemodynamics during CRT optimization. In a third of patients, there is worsening of RV filling at optimal AVD and VVD for LV. These data suggest that RV Doppler should be examined during CRT optimization to ensure lack of deterioration in RV filling at optimal pacemaker settings for LV.
- © 2012 by American Heart Association, Inc.