Abstract
Background Radiofrequency catheter ablation (RF-CA) of common atrial flutter (AFL) requires the creation of a transmural incision to create a bidirectional conduction block in the cavotricuspid isthmus (ITH). Methods and Results RF-CA of the ITH using a cooled-tip system was carried out in 40 patients. In the `conventional' mode (CONV) of the system, RF energy was applied for 2 min with the temperature set at 60°C and power of up to 50 W, and in the failed cases the `cooled-tip' mode (COOL) was utilized at 45°C with up to 30 W (with a 15 ml/min saline flow rate). Of the 40 patients, 29 crossed over from the CONV to the COOL after a failed ablation of the AFL. As a result, in all 40 patients a complete linear incision could be created with either the COOL or the CONV, resulting in the successful abolition of the AFL. Complete bi-directional block was successfully created in all patients. No significant side effects occurred. Conclusions The COOL was found to be more effective and just as safe as the CONV for AFL ablation, thus facilitating the rapid and complete elimination of the AFL. (Circ J 2004; 68: 73 - 76)