Meta-analysis of randomized controlled trials evaluating left ventricular vs. biventricular pacing in heart failure: effect on all-cause mortality and hospitalizations.

Aim Randomized controlled trials (RCTs) showed that biventricular (BiV) pacing reduces heart failure (HF) hospitalizations and mortality in patients with New York Heart Association (NYHA) class III-IV HF, left ventricular (LV) dysfunction, and wide QRS. We performed a systematic review and meta-analysis of the RCTs comparing LV-only vs. biventricular (BiV) pacing in candidates for cardiac resynchronization therapy (CRT). METHODS AND RESULTS: The systematic review selected five RCTs (out of 1888 analysed reports) with a cumulative number of 372 patients randomized to BiV pacing and 258 to LV-only pacing. The meta-analysis shows that BiV pacing is not superior to LV-only pacing and that these two pacing modalities do not differ with regard to death or heart transplantation [LV-only vs. BiV pacing odds ratio (OR) 1.24, 95% confidence interval (CI) 0.57-2.70 with the fixed effect model, OR 1.25, 95% CI 0.48-3.24 with the random effect model]. Specific data on hospitalizations were available only in two RCTs with a cumulative number of 127 patients randomized to BiV and 123 to LV-only pacing. The meta-analysis shows that BiV pacing is not superior to LV-only pacing and that these two pacing modalities do not differ with regard to this outcome (LV-only vs. BiV pacing OR 0.86, 95% CI 0.49-1.50 with the fixed effect model, OR 0.86, 95% CI 0.49-1.50 with the random effect model). CONCLUSIONS: Biventricular pacing is not superior to LV-only pacing, and these two pacing modalities appear to achieve similar efficacy in candidates for CRT for moderate to severe HF, in terms of all-cause mortality and hospitalizations during follow-up.