Positive impact of pulmonary vein isolation on biventricular pacing in nonresponders to cardiac resynchronization therapy

Background: Cardiac resynchronization therapy (CRT) is less effective in patients with atrial fibrillation (AF) because of impaired ventricular CRT capture.

Objective: We investigated the effects of catheter ablation in patients with AF and previous nonresponse to CRT.

Methods: Consecutive patients with AF and CRT nonresponse who underwent catheter ablation for AF were analyzed. CRT nonresponse was defined as one of the following: (1) reduced biventricular capture <95% due to rapidly conducted AF, (2) <1 point improvement in New York Heart Association (NYHA) class after CRT implantation, or (3) insufficient increase in left ventricular ejection fraction (LVEF; ≤5%) after CRT implantation.

Results: Thirty-eight patients (8 women [21%]; mean age 68 ± 10 years; LVEF 30% ± 7%, biventricular capture 88.0% [25th, 75th percentile 75.3%, 98.5%]) underwent catheter ablation. One major and 1 minor complication occurred (1 lethal atrioesophageal fistula and 1 hemodynamically nonrelevant pericardial effusion). The Kaplan-Meier estimates for arrhythmia-free survival after single and multiple ablation procedures were 29% (95% confidence interval 16%-51%) and 67% (95% confidence interval 53%-86%) after 24 months. After a median follow-up of 817 days (25th, 75th percentile 179, 1741 days), biventricular capture and LVEF were significantly higher (median [25th, 75th percentile] 99% [96%, 99%], difference 8% [0.2%, 3.75%], P < .0001; mean 32.1% ± 9.1%, difference 2.2% ± 7.1%, P = .0225) and patients had a significantly lower functional NYHA class (28 of 37 patients with improvement of at least 1 point; P < .0001).

Conclusion: Catheter ablation of AF significantly improves CRT response in patients with heart failure and concomitant AF in terms of increased biventricular capture and LVEF and improved functional NYHA class.