Comparison Between Contact Force Guided and Blinded Strategy on PV Isolation in AF Patients

Overview

Pulmonary vein (PV) isolation is very important in atrial fibrillation (AF) catheter ablation. PV reconnection is one of the main reasons in AF recurrence. Contact force-sensing catheter is a new catheter which has valuable tools to monitor and increase the efficacy of PV isolation. Previous paper reported the efficacy of contact force-sensing catheter on immediate PV isolation and outcome. However, there might be confounding factor as inter-individual variation. Therefore, we would like to compare the efficacy of contact force-sensing catheter within same patient but different veins. In this study, we would like to confirm the efficacy of contact force-sensing catheter on immediate PV isolation outcome within same patient. This study randomized the right or left PVs whether to use the contact force-sensing function or not. The study design will minimize the inter-individual variation on evaluating the efficacy of contact force-sensing catheter on immediate PV isolation. Also, in patients who had recurred AF or AT, we would like to evaluate the long-term efficacy of contact force-sensing catheter on PV isolation.

Sixty patients will be randomized to select right or left pulmonary veins whether to apply contact force-guided ablation or contact force-blinded ablation strategy. Each PV will be ablated with same contact force-sensing catheter (Thermocool Smart Touch Catheter, Biosense Webster Inc. CA). The PV (right or left) which will be randomized to contact force-sensing PV or blind PV. Contact force-sensing PV will be ablated guided by contact force, whereas the blind PVs will be ablated without contact force-sensing information. The change of impedance, total ablation and time to ablate PV will be collected and analysed according to contact force-sensing strategy. After exit and entrance block by conventional method, dormant conduction will be evaluated by using adenosine. The proportion of dormant conduction will be compared between contact force-sensing guided or blinded strategy. During 1-year follow up, patients who recurred AF or AT will be undergo second ablation procedure. In these patients, PV reconnection rate will be evaluated by a duodecapolar lasso circular mapping catheter. We would like to know whether PVs which have ablated with contact force-sensing information at index procedure have less reconnection than those which was ablated without contact force-sensing information.