The impact of robotic assistance on catheter contact force application during AF ablation

Abstract

Purpose: Increased catheter contact with the myocardium during ablation increases scarring and likelihood of local electrical isolation, but also carries a greater risk of procedural complications. We evaluated the impact of robotic-assistance on catheter force application during AF ablation Method: MAST-AF (Manual vs Amigo with SmartTouch AF Study) is an ongoing prospective randomized trial (NCT01583855) comparing the Amigo Remote Catheter System with manual AF ablation, using a force-measuring catheter and Carto 3 (SmartTouch). The same procedure (wide area circumferential ablation, WACA) was performed in all patients to isolate the pulmonary veins. The operator was blinded to force readings in both groups. WACA lesions were systematically grouped by region using a clock face model, then analysed retrospectively by another physician who was blinded to the technique used. Mixed-effects models were fitted to log-transformed data, using planned contrasts to compare the two groups at each region, and over all regions Results: From 10 robotic and 8 manual cases, 3329 ablation points were analysed, totalling 662, 471 force data elements. A trend towards higher values anterior to the R pulmonary vein ostia (RWACA 1-5; see figure) was found for Amigo cases. Both techniques applied similar overall mean force: LWACA - 8.2g (Amigo) vs 7.3g (manual); RWACA -10.2g (Amigo) vs 9.3g (manual). The standard deviation of the applied forces did not differ significantly, regionally nor overall, between the two groups (data not shown). (figure Presented) Conclusion: Catheter force application characteristics are similar with robot and manual procedures, but higher force values occur when ablating with the Amigo system adjacent to the aorta, mandating extra care when operating in this area.