Atrial Electroanatomic Remodeling After Circumferential Radiofrequency Pulmonary Vein Ablation: Efficacy of an Anatomic Approach in a Large Cohort of Patients With Atrial Fibrillation

Abstract

Background Circumferential radiofrequency ablation around pulmonary vein (PV) ostia has recently been described as a new anatomic approach for atrial fibrillation (AF). Methods and Results We treated 251 consecutive patients with paroxysmal (n=179) or permanent (n=72) AF. Circular PV lesions were deployed transseptally during sinus rhythm (n=124) or AF (n=127) using 3D electroanatomic guidance. Procedures lasted 148±26 minutes. Among 980 lesions surrounding individual PVs (n=956) or 2 ipsilateral veins with close openings or common ostium (n=24), 75% were defined as complete by a bipolar electrogram amplitude <0.1 mV inside the lesion and a delay >30 ms across the line. The amount of low-voltage encircled area was 3594±449 mm 2 , which accounted for 23±9% of the total left atrial (LA) map surface. Major complications (cardiac tamponade) occurred in 2 patients (0.8%). No PV stenoses were detected by transesophageal echocardiography. After 10.4±4.5 months, 152 patients with paroxysmal AF (85%) and 49 with permanent AF (68%) were AF-free. Patients with and without AF recurrence did not differ in age, AF duration, prevalence of heart disease, or ejection fraction, but the LA diameter was significantly higher ( P <0.001) in permanent AF patients with recurrence. The proportion of PVs with complete lesions was similar between patients with and without recurrence, but the latter had larger low-voltage encircled areas after radiofrequency (expressed as percent of LA surface area; P <0.001). Conclusions Circumferential PV ablation is a safe and effective treatment for AF. Its success is likely due to both PV trigger isolation and electroanatomic remodeling of the area encompassing the PV ostia.