Cardiac resynchronization and quality of life in patients with minimally symptomatic heart failure.

Abstract

This study compared the quality of life (QOL) of patients with cardiac resynchronization therapy (CRT) and an implantable cardioverter-defibrillator (ICD) to patients with an ICD only. CRT with ICD is associated with a reduction in heart failure risk among minimally symptomatic patients. It is unknown whether this improves QOL. This study uses the MADIT-CRT (Multicenter Automatic Defibrillator Implantation Trial With Cardiac Resynchronization Therapy) data. The MADIT-CRT enrolled 1,820 patients at 110 centers across 14 countries. Patients had ischemic cardiomyopathy (New York Heart Association [NYHA] functional class I or II) or nonischemic cardiomyopathy (NYHA functional class II only), sinus rhythm, an ejection fraction of 30% or less, and prolonged intraventricular conduction with a QRS duration of 130 ms or more. QOL was evaluated on the 1,699 patients with baseline and follow-up measures using the Kansas City Cardiomyopathy Questionnaire (KCCQ). Six dimensions (Physical Limitation, Symptom Stability, Symptom Frequency, Symptom Burden, Quality of Life, and Social Limitations) and 3 summary scores (Total Symptom, Clinical Summary, and Overall Summary) were analyzed. During an average follow-up of 2.4 years, the CRT-ICD group had greater improvement than the ICD-only group on all KCCQ measures (p < 0.05 on each scale). These differences were significant among patients with left bundle branch block conduction disturbance (n = 1,204, p < 0.01 on each scale), but not among patients without left bundle branch block (n = 494). Compared with patients with ICD only, CRT-ICD is associated with greater improvement in QOL among relatively asymptomatic patients, specifically among those with left bundle branch conduction disturbance.