Effect of cardiac resynchronization therapy and implantable cardioverter defibrillator on quality of life in patients with heart failure: a meta-analysis.

To compare the improvement of quality of life (QoL) in cardiac resynchronization therapy plus implantable cardioverter defibrillator (CRT-D) therapy with that in implantable cardioverter defibrillator (ICD) therapy alone for patients with heart failure. Medline, Embase, The Cochrane Library, and US Food and Drug Administration website were searched for published studies up to 31 December 2011. Studies were considered for inclusion if they were randomized controlled trials (RCTs) that compared the efficacy of CRT-D therapy with ICD therapy in patients with heart failure. The primary outcome of this study was improvement in QoL. Four RCTs with 1655 patients were included in this meta-analysis. Overall, the QoL score of patients in CRT-D group significantly improved [weighted mean difference (WMD): -6.02; 95% confidence interval (CI): -10.56 to -1.48] compared with that in the ICD only group. However, the benefit with respect to QoL in CRT-D group was not maintained when subset meta-analysis was performed in patients with New York Heart Association (NYHA) class I-II (WMD: 0.19; 95% CI: -3.89 to 4.72), whereas the patients with NYHA class III-IV in CRT-D group still experienced a significant improvement of QoL score compared with ICD group (WMD: -8.49; 95% CI: -13.39 to -3.59). CRT-D therapy improves the QoL compared with ICD therapy alone, especially in patients with moderate to severe heart failure.