Comparison of a 6.5, 10, and 15 mm cryoablation catheter-tip for the treatment of common atrial flutter

Abstract

Only a few studies have investigated the effect of large tip sizes for catheter-based cryoablation (cryo). This study evaluates the safety and efficacy of cryo of the cavotricuspid isthmus (CTI) using three cryocatheter-tip sizes. Forty-five consecutive patients with common atrial flutter (AFL) underwent cryo of the CTI using a 6.5, a 10, or a novel 15 mm catheter-tip. Single applications of 3 min were delivered at each site along the CTI. Baseline characteristics of the three groups were comparable. The overall acute success rate was 89% and there was no difference with respect to the tip electrode size (P > 0.05). Fewer applications were required for a 10 mm (6 ± 2, range 3-7) and a 15 mm (6 ± 1, range 4-8) compared with a 6.5 mm catheter-tip (8 ± 3, range 4-14; P < 0.05). Procedure time was significantly shorter with the largest tip electrode (89 ± 26 min vs. 132 ± 28 min (6.5 mm tip), P < 0.05). No complications occurred. After a mean follow-up of 51 ± 5 months, 43 patients (96%) were without recurrence of AFL. A large (10 or 15 mm) cryoablation catheter-tip requires significantly fewer applications to create bidirectional CTI block compared with a 6.5 mm tip. A significant decrease in procedure time with preservation of the overall safety and efficacy supports the preference of a 15 over a 6.5 mm catheter-tip for cryoablation of AFL.