Long-term outcomes of catheter ablation of atrial fibrillation in dilated cardiomyopathy.

OBJECTIVE

The long-term outcomes, efficacy and safety of catheter ablation in atrial fibrillation (AF) patients with dilated cardiomyopathy (DCM) have not been reported previously.

METHODS AND RESULTS

Forty nine patients with AF (59% longstanding persistent AF, LSP-AF) and DCM were enrolled. Circumferential pulmonary vein ablation (CPVA, paroxysmal AF), bidirectional block of lines and disappearance of complex fractionated atrial electrograms (CFAEs, persistent and LSP-AF) were the endpoints of the index and repeat procedures. Cumulative success rate reached 49% (mean, 1.4 procedures) during the first year, and dropped to 38% at median follow-up of 45 months (range, 36-64 months) for multiple procedures (mean, 1.9 ± 0.8 [1-4]). Incidence of procedural complications was similar to that of conventional procedures. In multivariate analysis, LSP-AF (OR, 7.40 [95% CI, 1.42-38.34]; P = 0.017) and larger left ventricular end-diastolic diameter (OR, 1.24 [95% CI, 1.01-1.52]; P = 0.034) were significant independent predictors of recurrent atrial tachyarrhythmia (ATa). Compared with patients with ATa recurrence, those free from ATa had better New York Heart Association functional class, 6-minute walk distance and left ventricular ejection fraction during long-term follow-up compared with pre-ablation, but this improvement was not sustained beyond 3 years.

CONCLUSION

In patients with DCM, current commonly used ablation strategies including CPVA, linear ablation and CFAE ablation are not associated with long-term AF treatment success up to five years. Freedom from ATa is associated with improved heart failure during but not beyond 3 years post ablation.