[Association between CHADS2 score and long-term atrial fibrillation recurrence rate after catheter ablation]

To investigate the association between CHADS2 score and long-term ( ≥ 3 years) outcomes post catheter ablation in patients with atrial fibrillation (AF).

AF patients who received single catheter ablation in our hospital from January 2004 to March 2009 in our department were included and patients received regular follow-up. AF recurrence was defined as the occurrence of atrial arrhythmias (AF, atrial flutter and atrial tachycardia) recorded by electrocardiogram monitor ( ≥ 30 seconds) after ablation during follow-up period (after 3 months blanking period). The relationship between baseline clinical and echocardiographic characteristics and the time to recurrence during follow-up was evaluated using Cox multivariate analysis.

A total of 280 patients who received single catheter ablation procedure were included in the study, 3 patients died and there were 50 patients lost to follow-up. A total of 227 patients with AF (163 paroxysmal and 64 non-paroxysmal ) were enrolled in the final analysis. During a median follow-up of 51 months (41-56 months), 109 patients experienced AF recurrences and the recurrence rate after catheter ablation ( ≥ 3 years) was 48.0% (109/227). Cox multivariate analysis showed that the high CHADS2 score (HR: 1.417, 95%CI 1.194-1.682, P < 0.001) and AF non-termination during ablation (HR: 2.077, 95%CI 1.380-3.126, P = 0.043) were risk factors of AF recurrence. AF recurrence rates in the termination and non-termination group were 41.0% (75/183) and 77.3% (34/44), respectively. In the AF termination group, the recurrence rates and the median recurrence free time in patients with CHADS2 score ≥ 3 were 80.0% (12/15) and 1 year, respectively. In the non-AF termination group, the recurrence rates in patients with CHADS2 score = 0, CHADS2 score = 1-2 and CHADS2 score ≥ 3 were 60.0% (6/10), 77.8% (21/27) and 100% (7/7), respectively; the median recurrence free time of patients with CHADS2 score = 0, CHADS2 score = 1-2 and CHADS2 score ≥ 3 were 30 months, 12 months and 6 months, respectively.

CHADS2 score is a predictor of AF recurrences after catheter ablation. Patients with high CHADS2 score is associated with higher risk of long-term ( ≥ 3 years) AF recurrences.