Proarrhythmic effects of atrial fibrillation ablation techniques.

BACKGROUND: The incidence of proarrhythmia induced by ablation for atrial fibrillation (AF) is not entirely known. We describe the incidence and management of atrial arrhythmias occurring after various techniques for the ablative therapy of AF. METHODS: Ninety-four patients with paroxysmal AF underwent ostial pulmonary vein (PV) ablation (n=54) or circumferential ablation around the PV ostia (n=40). RESULTS: Atrial tachycardia or flutter was detected during the first 6 months after AF ablation in 10 patients. Atrial arrhythmia was more common among patients who underwent circumferential ablation or circumferential with lines (18.2% and 22.2%, respectively) than in those who were treated with other techniques (p = 0.037). The incidence of atrial tachycardia or flutter among patients who underwent ostial ablation or ostial with lines was 2.4% and 8.3%, respectively. No difference was observed in the risk of atrial arrhythmia between patients who underwent ablation with or without additional lines, either ostial (p = 0.398) or circumferential (p = 0.999). Re-ablation was performed in 7 patients with sustained atrial arrhythmia. At 6 months, no recurrence of atrial tachycardia or flutter was.seen in 6 of these patients, nor in 3 patients with non-sustained atrial tachycardia or flutter. CONCLUSIONS: The incidence of atrial tachycardia or flutter following AF ablation is lower for ostial than for circumferential ablation. The addition of lines along the mitral isthmus and between the superior PVs does not significantly affect the risk of ablation-induced arrhythmia. Non-sustained atrial tachycardia or flutter during or early after AF ablation procedures does not require additional ablation.