Long-term left ventricular pacing: assessment and comparison with biventricular pacing in patients with severe congestive heart failure.

OBJECTIVE The purpose of this study is to report prospectively the results of six-month follow-up of permanent left ventricular (LV) based pacing in patients with severe congestive heart failure (CHF) and left bundle branch block (LBBB). BACKGROUND Left ventricular pacing alone has been demonstrated to result in identical improvement compared to biventricular pacing (BiV) during acute hemodynamic evaluation in patients with advanced CHF and LBBB. However, to our knowledge, the clinical outcome during permanent LV pacing alone versus BiV pacing mode has not been evaluated. METHODS Pacing configuration (LV or BiV) was selected according to the physician's preference. Patient evaluation was performed at baseline and at six months. RESULTS Thirty-three patients with advanced CHF and LBBB were included. Baseline characteristics of LV (18 patients) and BiV (15 patients) pacing groups were similar. During the six-month follow-up period, seven patients died three BiV and four LV). In the surviving patients at 6 months, 8 of 14 patients in the LV group and 9 of 12 in the BiV group were in New York Heart Association class I or II (p = 0.39). No significant difference was observed between the two groups in terms of objective parameters except for LV end-diastolic diameter decrease (-4.4 mm in BiV group vs. -0.7 mm in LV group; p = 0.04). CONCLUSION At six-month follow-up, a trend toward improvement was observed in objective parameters in patients with severe CHF and LBBB following LV-based pacing. The two pacing modes (LV and BiV) were associated with almost equivalent improvement of subjective and objective parameters.