Abstract 13444: Complete Left-Sided Reverse Remodeling in Cardiac Resynchronization Therapy and Clinical Implications: a MADIT-CRT Long-term Follow-up Sub-study
Background: Left ventricular and left atrial remodeling (defined as a reduction in left ventricular end-systolic volume [LVESV] and left atrial volume [LAV] respectively) have both been shown to be associated with better clinical outcome in patients with cardiac resynchronization therapy (CRT). However, a portion of CRT patients exhibit discordant remodeling (e.g. improvement in LVESV but not in LAV or vice versa). Whether combined assessment of LA and LV remodeling predicts clinical outcome is unknown. Objectives: We aimed to evaluate the predictive value of a combined assessment of LAV and LVESV change in CRT patients with left bundle branch block (LBBB) enrolled in MADIT-CRT. We hypothesized that combined assessment better predicts outcome than LAV or LVESV reduction alone. Methods: The study population comprised 533 CRT-D LBBB patients assigned to lesser remodeling (below median LAV and LVESV change), discordant remodeling (above median change in only LAV or LVESV), or complete left-sided remodeling (above median change in both LAV and LVESV). The end point was heart failure (HF) during follow-up. Results: At 1-year follow-up, 206 patients had lesser remodeling, 115 had discordant remodeling and 212 had complete left-sided remodeling. Patients with complete left-sided remodeling had less HF than those with discordant remodeling or lesser remodeling (Figure, p=0.002). Multivariate analysis confirmed that complete left-sided remodeling is associated with lower risk of HF than discordant remodeling and discordant remodeling is better than lesser remodeling (HR=0.62 per each group, 95% CI: 0.44-0.86, p = 0.004). Conclusions: A combined assessment of LAV and LVESV reduction predicts HF in CRT patients with LBBB. Patients with complete left-sided remodeling had a significantly lower risk of HF during long-term follow-up.