Cryoablation versus radiofrequency ablation in the treatment of atrial flutter trial (CRAAFT).

INTRODUCTION

Atrial flutter is frequently treated with radiofrequency (RF) ablation with excellent results. While RF ablation remains the gold standard for catheter based treatment of atrial flutter, cryoablation has potential advantages including painless ablation and cryoadherence to the myocardium. We performed a prospective randomised trial comparing cryoablation and RF ablation in the treatment of atrial flutter.

METHODS AND RESULTS

We randomised 32 consecutive patients with typical atrial flutter to either radiofrequency ablation using an 8 mm tip Blazer II XP catheter (EP Technology, San Jose, USA) or cryoablation using a 9 French 8 mm tip Freezor Max catheter (CryoCath Technologies Inc, Kirkland, QU, Canada). Twenty eight patients were then followed up for a mean of 14.7 months. The procedure was successful in producing isthmus block in all but one patient in the cryoablation group. Cryoablation was associated with a significantly longer procedure (171 vs 99 min) and ablation duration (59 vs 12.7 min), however fluoroscopy exposure was similar (30 vs 29 min). Cryoablation was associated with reduced pain scores compared with RF (mean pain score 0.4 vs 3.5). There were two recurrences of atrial flutter during follow-up, both in the cryoablation group.

CONCLUSIONS

Cryoablation has improved patient tolerability compared to RF ablation, however is associated with longer procedure and ablation durations. Further trials are required to confirm whether cryoablation has similar acute and chronic efficacy to RF ablation.