EP News

Abstract

Hocini et al (Circulation 2005;112:3688) prospectively randomized 90 patients with drug-refractory paroxysmal atrial fibrillation (AF) undergoing radiofrequency (RF) ablation into two ablation strategies: (1) pulmonary vein (PV) isolation (n = 45) or (2) PV isolation in combination with linear ablation joining the two superior PVs (roofline; n = 45). Roofline ablation was performed at the most cranial part of the left atrium (LA) with complete conduction block demonstrated during LA appendage pacing. PV isolation was achieved in all patients. Roofline ablation required 12 ± 6 minutes (median 11, range 3–25) of RF energy delivery. Complete block was confirmed in 43 patients (96%) and resulted in a significant increase in the fibrillatory cycle length, termination of arrhythmia in 47% (8/17), and subsequent noninducibility of AF in 59% (10/17) of patients inducible after PV isolation. However, LA flutter, predominantly perimitral, could be induced in 10 patients (22%) after roofline ablation. At 15 ± 4 months, 87% of the roofline group and 69% with PV isolation alone are arrhythmia-free without antiarrhythmics (P = .04). The authors concluded that complete linear block at the LA roof resulted in prolongation of the fibrillatory cycle, termination of AF, and subsequent noninducibility and is associated with an improved clinical outcome compared with PV isolation alone.