Abstract 13412: Cardiac Resynchronization Therapy with Multisite Left Ventricular Pacing Improves Acute Hemodynamic Response in Patients
Cardiac resynchronization therapy (CRT) with single site left ventricular (LV) pacing improves acute hemodynamics. We hypothesized that CRT with multisite LV pacing in a single coronary sinus (CS) branch can offer further acute hemodynamic benefits to patients (pts). Thirteen pts receiving a CRT implant (Unify Quadra MP™ and Quartet™ LV lead, St. Jude Medical) underwent LV hemodynamic assessment using a pressure-volume (PV) loop system (Inca, CD Leycom). PV loops were recorded during biventricular pacing with each of two single LV sites and with 4-8 multisite LV pacing settings. Each pacing intervention was performed twice in a randomized order with right ventricular pacing (BASELINE) repeated after every test configuration. Valid PV loops were obtained in 12 pts. Compared to BASELINE, a multisite LV pacing configuration resulted in the greatest improvement in maximum pressure change (dP/dtMax) in 12/12 pts. The best multisite LV pacing configuration increased dP/dtMax by 16.7±12.7% (range: 0.4 - 44.4%) over BASELINE, significantly more than the best single site LV pacing configuration (12.4±8.5%, range: 0.3 - 29.8%, p = 0.018, Fig. A). Representative PV loops (Fig. B) illustrate the expansion of the loop that occurs during the best multisite LV pacing configuration. In this patient, dP/dtMax (relative to BASELINE), stroke work (SW), and stroke volume (SV) increased from 11.0%, 5.3 mmHg*L, and 74 mL during the best single site LV pacing configuration to 12.7%, 5.9 mmHg*L, and 79 mL during the best multisite LV pacing configuration, respectively. Multisite LV pacing in a single CS branch can significantly improve LV hemodynamic properties relative to single site LV pacing.
- © 2012 by American Heart Association, Inc.