Background: During catheter ablation, atrial fibrillation (AF) can be terminated in various modes, directly in sinus rhythm or evolved into a regular atrial tachycardia (AT) and, subsequently, in sinus rhythm or after direct current (DC) cardioversion. The aim of the present study was to evaluate the influence of termination mode on clinical outcomes in patients who underwent an ablation approach aiming at AF termination.
Methods and Results: This prospective study included 399 consecutive patients (62.7 ±7.2) who underwent catheter ablation for drug-refractory persistent AF (4.6±2.4 months), using a stepwise ablation approach. A 12-month follow-up with repeated Holter monitoring was carried out. In 136 patients, the AF was terminated by radiofrequency application during catheter ablation directly in sinus rhythm. In 194 patients, sinus rhythm was restored via AT and, in the remaining 69 patients, sinus rhythm was restored by DC cardioversion after catheter ablation. During the follow-up, the patients in whom AF terminated after AT had a lower recurrence rate of atrial tachyarrhythmias than the patients in whom AF had terminated directly in sinus rhythm or after dc-cardioversion (19.6% vs. 27.9% and 71% respectively; p <0.001). The patients with recurrence of atrial arrhythmia who converted directly to sinus rhythm had a higher recurrence rate of AF (94.7% ) as compared to patients who converted via AT (13.2%; p<0.001). Multivariable logistic regression analysis demonstrated that termination of AF via AT during ablation (HR 0.44; 95% CI: 0.25-0.77, P = 0.004), DC cardioversion (HR 3.26; 95% CI: 1.57-6.77) and baseline atrial fibrillation cycle length, (HR 0.95; 95% CI: 0.92-0.98; p = 0.005) were significant independent factors predicting the recurrence of atrial arrhythmia.
Conclusions: The termination of AF after AT during catheter ablation is associated with a better clinical outcome in patients with AF.