Impact of baseline left ventricular volume on left ventricular reverse remodeling after cardiac resynchronization therapy.

Abstract

Left ventricular (LV) dilatation may limit LV reverse remodeling after cardiac resynchronization therapy (CRT). The purpose of this study was to evaluate the impact of baseline LV volumes on LV reverse remodeling after CRT and whether this is associated with improved survival. Patients were stratified into quintiles according to baseline LV end-diastolic volume indexed for body surface area (LVEDVi). LV reverse remodeling was defined as ≥15% reduction in LV end-systolic volume at 6-month follow-up after CRT. Independent associates of LV remodeling were assessed and long-term mortality rates were compared between patients with and without LV reverse remodeling (across LVEDVi quintiles). A total of 864 patients were included (mean age 66 ± 10 years; 657 patients (76%) were male), of whom 101 (12%) were in quintile 1 (<65 mL/m2), 272 (32%) in quintile 2 (65-95 mL/m2), 247 (29%) in quintile 3 (95-125 mL/m2), 151 (18%) in quintile 4 (125-155 mL/m2), and 93 (11%) in quintile 5 (>155 mL/m2). Patients with larger baseline LVEDVi had worse survival after CRT (log-rank, P = .019). The cumulative 10-year survival was significantly better in patients with vs without LV reverse remodeling (48.7% vs 33.9%; P < .001). Significant LV reverse remodeling was observed in all LVEDVi quintiles. In addition, patients with LV reverse remodeling had superior survival than did patients without LV reverse remodeling, regardless of baseline LVEDVi quintile (log-rank, P < .05 for all). Many patients with larger baseline LV volumes still show significant LV reverse remodeling after CRT and had superior survival (regardless of baseline LV volumes) than did patients without LV reverse remodeling. Therefore, CRT should not be denied on the basis of severe LV dilatation.