Combined circular multielectrode catheter and point-by-point ablation is superior to point-by-point ablation alone in eliminating atrial fibrillation

Abstract

Background: Besides conventional point-by-point ablation, novel multielectrode catheters emerge for ablation of atrial fibrillation (AF). We sought to evaluate the clinical utility of a pulmonary vein (PV) isolation approach combining the advantages of both technologies.

Methods: The study included 240 consecutive AF patients (60±11 years, 68% males, 62% paroxysmal). In the combined ablation group (n=120), PV isolation was performed with a circular multielectrode catheter (PVAC, Medtronic Ablation Frontiers) and completed by conventional point-by-point ablation (NaviStar ThermoCool Catheter, Lasso/CARTO technology, Biosense Webster). In the point-by-point ablation group (n=120), PV isolation was performed with point-by-point ablation alone.

Results: Complete 1-year ablation success (freedom from any atrial arrhythmia off antiarrhythmic drugs) was more frequently observed in the combined ablation group (58.0% versus 43.3%, hazard ratio 1.72, 95% confidence interval 1.19-2.48, p=0.004). Also clinical success (≥90% reduction of arrhythmia burden on/off antiarrhythmic drugs) was significantly associated with the combined ablation approach (p=0.001). These associations remained significant after multivariable adjustment (both p≤0.005) and were not dependent on the type of AF. The rate of major adverse events (3.3% versus 2.5%) and the procedure time did not differ between groups. The fluoroscopy time, however, was significantly shorter in the combined ablation group (p<0.001) reflecting the reduced need for radiation during multielectrode catheter ablation.

Conclusions: A combined PV isolation approach based on multielectrode catheter ablation and complementary point-by-point ablation is superior to point-by-point ablation alone and reveals to be safe. A potential explanation for these findings is the improved durability of ablation lesion after the combined ablation approach.

Keywords: Atrial fibrillation; Multielectrode catheter ablation; Point-by-point ablation; Pulmonary vein isolation; Success.