2.3 | Follow-up and redo procedure
Patients were followed up after 3, 6 and 12 months. During follow-up, a 7-day Holter ECG was recorded. Arrhythmia recurrence was defined as atrial fibrillation, atrial tachycardia or atrial flutter on a 12-lead ECG or on a rhythm strip with ≥ 30 seconds duration, after a blanking period of 3 months. Patients were offered a redo procedure as deemed clinically appropriate. At the beginning of all redo procedures, an electroanatomical 3D voltage map of the left atrium was generated and mitral isthmus block reassessed.