Primary closed cooled tip ablation of typical atrial flutter in comparison to conventional radiofrequency ablation.

The purpose of this prospective, non-randomized study was to investigate the effectiveness of cooled radiofrequency ablation (cRFA) compared with conventional radio-frequency application (RFA) for ablation of typical atrial flutter (AF). Methods Isthmus ablation was carried out using a system with a circulating fluid path through the ablation tip to control tip temperature in 100 patients with AF. Thirty consecutive AF patients underwent conventional RFA. The number of applications for cRFA was 13.7 +/- 6.9 and for RFA 24.0 +/- 14-5 (P<0.0007) at powers between 35 and 50 W and a tip temperature range of 38-43 degrees C. Ablation duration and fluoroscopy time were 9-9 +/- 4.9 and 22-8 +/- 10.7 min for cRFA, respectively. In contrast, for RFA, ablation duration and fluoroscopy time were 20-6 +/- 14.2 (P<0.0001) and 27.4 +/- 12.7 min, respectively. In 93% of the cooled tip group and in 80% of the control group bi-directional block was confirmed. At 6-months follow-up, recurrence rates were 9 in the cooled-tip group and 7 in the control group, corresponding 10.4% and 25.9%. There were no significant complications. Compared with RFA, cRFA requires lower application numbers. Recurrence rates are low and the overall success rate is high.