Electrical Connections Between Pulmonary Veins Implication for Ostial Ablation of Pulmonary Veins in Patients With Paroxysmal Atrial Fibrillation

Background—Electrical disconnection of the myocardial extensions into arrhythmogenic pulmonary veins (PVs) isrecognized as a curative technique for paroxysmal atrial fibrillation (AF). However, the presence of electricalconnections between the PVs, which may make achievement of PV disconnection difficult, has not been systematicallyevaluated.Methods and Results—Forty-nine consecutive patients with drug-resistant AF underwent ostial radiofrequency (RF)catheter ablation of arrhythmogenic PVs with foci triggering AF. Pacing from inside the targeted PV was performedafter each RF delivery to identify the left atrial exit site of the residual venoatrial conduction. Successful PVdisconnection was defined as achieving elimination of the PV potentials during sinus rhythm or left atrial pacing, andthe loss of left atrial conduction during intra-PV pacing. A total of 112 arrhythmogenic PVs were identified. PVdisconnection was achieved with 10 6.1 minutes of RF delivery to the ostia of 101 targeted PVs. In 7 left superior (LS)PVs from 7 patients (14%), the earliest atrial activity was recorded from the left inferior (LI) PV ostium duringintra-LSPV pacing after 11 4.7 minutes of RF delivery to the LSPV ostium. Disconnection of these LSPVs wasachieved by LIPV disconnection. In the remaining 4 PVs from 4 patients, PV disconnection could not be achieved.Conclusions—Fourteen percent of the patients had electrical connections between contiguous PVs. In these patients, ostialablation of an untargeted PV was required for successful targeted PV disconnection. (Circulation. 2002;105:2998-3003.)Key Words: fibrillation catheter ablation veins atrium