Abstract 12785: In Patients Supported by a Left Ventricular Assist Device, Bi-Ventricular Pacing does not Offer Hemodynamic Improvement over Right Ventricular Pacing

Abstract

Hypothesis: The benefit of biventricular (BiV) pacing in patients supported by a left ventricular assist device (LVAD) is unknown. This pilot study aimed to assess the acute hemodynamic effects of biventricular pacing compared to right ventricular (RV) pacing in patients supported by LVADs and to determine appropriate pacing rate. Methods: We studied 7 patients (age 65±7, 100% males) supported by Heartmate II (HM2) LVAD who underwent biventricular (BiV) pacemaker (PM) implant prior to LVAD. All patients underwent a ramp echo study for speed optimization prior to enrollment. Two patients were in sinus rhythm and 5 were in chronic atrial fibrillation (AF) and pacemaker dependent due to complete atrioventricular block (AVB). Results: A total of 42 complete sets of hemodynamics were obtained during BiV and RV pacing at various pacing rates ranging from 50 to 110 bpm. There were no significant differences in right atrial(RA) pressure, mean pulmonary artery(mPA) pressure, cardiac index(CI), PA saturation(PASat) and right ventricular stroke work index(RVSWI) between BiV and RV pacing (table). There was a trend for higher stroke volume index (SVI) and RVSWI at lower heart rates for each individual patient. Conclusion: BiV pacing does not appear to have any acute hemodynamic benefit compared to RV pacing in patients supported by HM2-LVAD. At lower heart rate, whether BiV or RV, may confer better RV efficiency.