During the past decade, catheter ablation of atrial fibrillation (AF) has evolved rapidly from an investigational procedure to its current status as a commonly performed ablation procedure in many major hospitals throughout the world. Surgical ablation of AF, using either standard or minimally invasive techniques, is also performed in many major hospitals throughout the world.

Background —The pulmonary veins (PVs) and surrounding ostial areas frequently house focal triggers or reentrant circuits critical to the genesis of atrial fibrillation (AF). We developed an anatomic approach aimed at isolating each PV from the left atrium (LA) by circumferential radiofrequency (RF) lesions around their ostia. Methods and Results —We selected 26 patients with resistant AF, either paroxysmal (n=14) or permanent (n=12). A nonfluoroscopic mapping system was used to generate 3D electroanatomic LA maps and deliver RF energy. Two maps were acquired during coronary sinus and right atrial pacing to validate the lateral and septal PV lesions, respectively. Patients were followed up closely for ≥6 months. Procedures lasted 290±58 minutes, including 80±22 minutes for acquisition of all maps, and 118±16 RF pulses were deployed. Among 14 patients in AF at the beginning of the procedure, 64% had sinus rhythm restoration during ablation. PV isolation was demonstrated in 76% of 104 PVs treated by low peak-to-peak electrogram amplitude (0.08±0.02 mV) inside the circular line and by disparity in activation times (58±11 ms) across the lesion. After 9±3 months, 22 patients (85%) were AF-free, including 62% not taking and 23% taking antiarrhythmic drugs, with no difference ( P =NS) between paroxysmal and permanent AF. No thromboembolic events or PV stenoses were observed by transesophageal echocardiography. Conclusions —Radiofrequency PV isolation with electroanatomic guidance is safe and effective in either paroxysmal or permanent AF.

Research from JAMA — Comparison of Antiarrhythmic Drug Therapy and Radiofrequency Catheter Ablation in Patients With Paroxysmal Atrial Fibrillation — A Randomized Controlled Trial

Background— There are no data to evaluate the relationship between autonomic nerve function modification and recurrent atrial fibrillation (AF) after circumferential pulmonary vein ablation (CPVA). This study assesses the incremental benefit of vagal denervation by radiofrequency in preventing recurrent AF in a large series of patients undergoing CPVA for paroxysmal AF. Methods and Results— Data were collected on 297 patients undergoing CPVA for paroxysmal AF. Abolition of all evoked vagal reflexes around all pulmonary vein ostia was defined as complete vagal denervation (CVD) and was obtained in 34.3% of patients. Follow-up ended at 12 months. Heart rate variability attenuation, consistent with vagal withdrawal, was detectable for up to 3 months after CPVA, particularly in patients with reflexes and CVD, who were less likely to have recurrent AF than those without reflexes ( P =0.0002, log-rank test). Only the percentage area of left atrial isolation and CVD were predictors of AF recurrence after CPVA ( P <0.001 and P =0.025, respectively). Conclusions— This study suggests that adjunctive CVD during CPVA significantly reduces recurrence of AF at 12 months.