Use of preprocedural multidetector computed tomography to decrease atrial fibrillation recurrence following extensive encircling circumferential pulmonary vein isolation

Abstract

BackgroundMyocardial thickness is particularly thick at the ridge between the left pulmonary vein (PV) and the left atrial appendage (LAA) by dissection. We investigated whether atrial fibrillation (AF) ablation outcome was influenced by altering ablation strategies according to the thickness of the PV–LAA ridge using preprocedural multidetector computed tomography (MDCT). Methods and resultsPatients with AF scheduled for extensive encircling circumferential pulmonary vein isolation (EEPVI) (110 patients) were divided into 2 groups. In the nonmodulation group (32 patients), EEPVI lines were created using a 3.5-mm tip irrigated catheter at a maximum power of 30W for 20–30s at each site. In the modulation group (78 patients), ablation was extended (40–60s) at the PV–LAA ridge if its thickness was >4.0mm on MDCT examination. Extended ablation at the PV–LAA ridge was noted in 37 patients in the modulation group. During 25±9 months of follow-up, recurrence was significantly less in the modulation group than in the nonmodulation group (10% vs. 28%; p=0.018). Logistic regression analysis showed that modifications in the ablation time and left atrium volume index were independent predictors of arrhythmia-free recovery after ablation. ConclusionsRecurrence following EEPVI could be reduced by modifications in the ablation time at the PV–LAA ridge.