Long-term follow-up
All patients were followed up for at least 12 months. We saw all patients at every 0.5, 1, 2, 3, 4, and 6 months, and every 6 months thereafter. Anticoagulation drugs were also used for at least 3 months and were continued based on the patients’ risk for thrombus embolisms determined using the CHADS2 or CHA2DS2-VASc score.12Each doctor decided whether or not to use AADs. The 12-lead electrocardiogram (ECG) and clinical assessments were performed at each visit. Further, 24h-Holter monitoring was performed at 0.5, 1, 2, 3, and 6 months after the initial ablation and every 6 months thereafter. The study patients were asked to record all episodes of any symptoms suggestive of arrhythmias such as palpitations, dizziness, or shortness of breath and report that to us as soon as possible. In such cases, an immediate ECG and 24 h Holter monitoring at the nearest clinic during the symptomatic period were suggested. Recurrence was defined as atrial arrhythmia episodes including AF, atrial flutter, and other atrial tachycardias lasting more than 30s after the first 3-month blanking period.