Follow up
Patients in the VOLCANO trial were followed for 12 months. After this protocol period, follow up was continued for 1 years or more (≥ 2 years after the index ablation procedure), usually every 3 months. Routine electrocardiograms (ECGs) were conducted at each outpatient visit. When patients experienced symptoms suggestive of an arrhythmia, surface ECG, ambulatory ECG, and/or cardiac event recording were also conducted at the discretion of the attending physician. AF or atrial tachycardia (AT) recurrence was defined as the occurrence of one of the following events: (1) AF/AT indicated on a routine or symptom-triggered ECG during an outpatient visit; or (2) AF/AT of at least 30-s duration on ambulatory ECG monitoring. AF/AT episodes during the 3 months after the initial or repeat ablation were not included in the recurrence events (blanking period). No AADs were prescribed after the ablation procedure unless AF/AT recurrence was observed.