Voltage mapping and pacing to assess the level of pulmonary venous isolation achieved with a novel circular multielectrode ablation catheter

AIMS: The aim of the study was to determine the level of pulmonary vein (PV) isolation achieved with the use of a novel radiofrequency circular multielectrode ablation catheter [pulmonary vein ablation catheter (PVAC)] in patients with paroxysmal atrial fibrillation. Although some efficacy data have been presented, the level of PV isolation, which is crucial both for efficacy and safety of the ablation, has not been defined with this new ablation catheter. METHODS AND RESULTS: Detailed sinus rhythm voltage maps using an electroanatomic mapping system and projected on 3D computed tomography-derived reconstructions of the left atrium (LA) were obtained before and after PV isolation with the PVAC. Left atrium-PV entry and exit block was assessed for each vein. The population consisted of 12 patients, mean age 57+/-6 years, seven male. After ablation, an extensive zone of potential reduction that included the ostium of each PV was observed in all patients. Bipolar voltages were significantly reduced in all PVs and in the LA close to the vein ostia, the mean voltage reduction was >80%. CONCLUSION: Using the PVAC, (i) PVs are isolated at the level of the PV ostium and, importantly, outside the tubular portion and (ii) significant voltage reduction is also recorded at various extent proximal to the PV ostium at the level of the antral region.