Introduction and objectives: Both 8-mm-tip and irrigated-tip catheters improve outcomes in typical atrial flutter ablation. However, it is not yet known which is preferable. The objective was to compare the effectiveness of 8-mm-tip (Group 1) and open irrigated-tip (Group 2) catheters in the first ablation attempt.
Methods: A prospective randomized trial with a long-term follow-up was performed in patients with documented typical atrial flutter. For both types of catheter, the power was initially set to 50 W. The primary endpoint was ablation of the cavotricuspid isthmus in a procedure lasting, at most, 600 s.
Results: Group 1 contained 65 patients and Group 2 contained 66, with no significant intergroup difference in baseline characteristics. Their mean age was 63+/-12 years, 80% were men, and 65% had structural heart disease. The primary endpoint was achieved in 48 patients (73.8%) in Group 1 and 49 (74.2%) in Group 2 (P=NS). In the remaining patients, the procedure was continued at the physician's discretion and ablation was finally achieved in all cases. In the intention-to-treat analysis, there was no significant difference between the groups in the number of applications of the ablation device or in the duration of the ablation procedure, radioscopy or the total procedure. By 16+/-5 months of follow-up (>1 year in 98%), 8 (6.3%) patients had experienced recurrence and 95 (74.2%) were free from any arrhythmia. There was no differences between the groups.
Conclusions: No difference was found between the effectiveness of 8-mm-tip and open irrigated-tip catheters in the first attempt at ablation of typical atrial flutter.