Pulmonary vein isolation without left atrial mapping

BACKGROUND: One of the crucial points during in most approaches developed for ablation of atrial fibrillation (AF) is the ability to identify the pulmonary vein (PVs) and to accurately locate their ostia. Objectives: The purpose of this case series was to investigate a simplified method for fusion of the multislice computer tomography (CT) derived 3D dataset with the electroanatomical map in order to facilitate the mapping procedure. METHODS: In 5 consecutive patients (4 male) referred for catheter ablation of symptomatic drug-refractory paroxysmal atrial fibrillation contrast enhanced computer tomography was performed before the procedure and imported into an electroanatomical mapping system (Carto XP) using CartoMerge Image Integration Module. During the procedure a multipolar mapping catheter (Quick Star DS, Biosense Webster, Diamond Bar, CA, USA) was introduced to the coronary sinus (CS) to align the CSCT shell to the proper position. The CS potentials provided information to identify the ostium of the CS to achieve a more accurate fusion of the images. No mapping points were taken in the left atrium. The feasibility of the method was characterized by the distance of mapping points. Mapping, registration and outcome data were compared with a cohort of patients undergoing MRI image integration. RESULT: The mean distance between the mapping points taken in the CS by the Quick Star catheter and the CS CT surface was suitable (mean±SD, 1.4±0.3 mm). Full electrical isolation of the pulmonary veins could be achieved in all patients. The mean procedure and fluoroscopy time were 39 ± 22 and 134 ±38 min respectively, significantly decreased as compared to the MRI cohort. CONCLUSIONS: Highly accurate CT image and the electroanatomical map (EAM) fusion can be obtained by the Carto 3D electromanatomical mapping system using CS as the key anatomical structure for registration. Using this technique the mapping time of the left atrium can be reduced.