Short-term effects of right ventricular pacing on cardiorespiratory function in patients with a biventricular pacemaker

The intention of this study was to evaluate the short-term effect of right ventricular (RV) pacing on cardiorespiratory function in patients with a biventricular pacemaker. A group of 26 patients with a biventricular pacemaker was enrolled in this cross-over, single-blind study. All patients underwent spiroergometry and electrocardiography in RV and biventricular pacing mode. Peak work capacity (102+/-32 W and 107+/-34 W for RV and biventricular pacing mode, respectively; P>.01) and peak oxygen consumption (21.4+/-6.7 mL/min/kg and 22.6+/-7.0 mL/min/kg for RV and biventricular pacing mode, respectively; P>.01) were significantly lower in the RV pacing mode. Heart rate at rest was significantly higher with active RV pacing. Short-term RV pacing in patients with a biventricular pacemaker resulted in a higher heart rate at rest, a lower peak work capacity, and a lower peak oxygen consumption compared with that in the biventricular pacing mode.