Association of rate-controlled persistent atrial fibrillation with clinical outcome and ventricular remodelling in recipients of cardiac resynchronization therapy

Abstract

Background: Whether patients with persistent atrial fibrillation (AF) obtain the same degree of benefit with cardiac resynchronization therapy (CRT) as those in sinus rhythm remains unclear.

Methods: We enrolled 93 patients undergoing CRT implantation, 20 (22%) of whom had rate-controlled persistent AF. The primary endpoint was CRT response defined as 1 class improvement in Specific Activity Scale and 15% reduction in left ventricular end-systolic volume (LVESV) during 12 months. Other endpoints included changes in 6-minute walk distance, quality of life, B-type natriuretic peptide, and survival.

Results: Baseline characteristics were similar in those with and without AF. Response to CRT was observed in 42% vs 54% of those with and without AF, respectively (P=0.3). Both groups had significant improvements in 6-minute walk distance, quality of life, and LVESV, but the improvement in LVESV was smaller in those with AF (13.7%±14.9% vs 27.7%±23.7%; P=0.02). During 2.8±1.4 years of follow-up, AF was associated with a 2.2-fold increased risk of death or transplantation (95% confidence interval, 1.2-3.9; P=0.01).

Conclusions: Compared with patients without rate-controlled persistent AF, those with rate-controlled persistent AF had similar rates of clinical improvement but less left ventricular reverse remodelling in the first year after CRT. AF was associated with a markedly higher risk of death or transplantation in long-term follow-up. Given these findings, randomized studies assessing CRT efficacy in those with AF are warranted.