Radiofrequency Catheter Selection Based on Cavotricuspid Angiography Compared with a Control Group with an Externally Cooled‐Tip Catheter: A Randomized Pilot Study

BACKGROUND: Radiofrequency ablation (RFA) of cavotricuspid isthmus (CTI)-dependent atrial flutter (AFL) can be performed using either externally cooled-tip RFA catheters or large-tip (8 mm) catheters. However, experimental and clinical studies suggest that the efficacy of both catheters may vary with CTI anatomy and catheters orientation. OBJECTIVES: The aim of this prospective study was to evaluate: a RFA catheter selection based on CTI angiography compared with a control group with an externally cooled-tip catheter together with the risk of an expensive crossover catheter in both groups. METHOD: Over a period of 16 months, 119 patients were included and randomized. RESULTS: When comparing the angiographic group (n = 56) and the externally cooled-tip RFA catheter group (n = 63), the duration of application time with a median of 7 min (interquartile range 4.5-11) versus a median of 10 min (interquartile range 6-20; P = 0.008) and the duration of X-ray exposure with a median of 7 min (interquartile range 4-10) versus a median of 10 min (interquartile range 5-15; P = 0.025) were significantly lower in the angiographic group versus externally cooled-tip catheter group. Furthermore, the number of catheters crossover was significantly higher in the angiographic group versus externally cooled-tip catheter group I (27% vs 7%; P = 0.007). CONCLUSIONS: This study shows that a strategy with a catheter selection based on a CTI angiographic evaluation is superior to an empirical use of an externally cooled-tip catheter during CTI RFA. Thus, angiographic isthmus evaluation predicts the effectiveness of a RFA catheter and the risk of an expensive catheter crossover.