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.