Cavotricuspid isthmus ablation by means of very high power short duration temperature controlled lesions: acute and mid term outcome

FUNDING ACKNOWLEDGEMENTS: Type of funding sources: None. BACKGROUND: Very high-power short-duration (vHPSD) temperature-controlled radiofrequency ablation minimizes conductive heating and increase resistive heating, achieving uniform and transmural lesion while reducing the risk of collateral tissue damages. The shape of the vHPSD lesion, wider and shallower than standard radiofrequency, raises some concerns during atrial flutter ablation (AFL). PURPOSE: We evaluated the feasibility, efficacy and safety of the vHPSD ablation of the cavotricuspid isthmus (CTI) in patients presenting with typical AFL. METHODS: Sixty-one consecutive patients, with typical AFL, underwent CTI ablation using the QDot Micro catheter and vHPSD (90 w for 4 s). Patients were followed-up by means of visits and ECG in the outpatient clinic 1, 6 and 12 months after the procedure and later on with telephone interviews or by 24-h Holter monitoring in case of symptoms. RESULTS: Acute CTI bidirectional block was achieved in all patients (91% of first-pass block) with a mean fluoroscopy time of 114±29 s and a mean procedure time of 37±9 min. Two steam pops were observed. Two patients had groin hematoma, no further complications were observed. During a mean follow-up of 14±7 months, two (3.2%) patient had typical AFL recurrence, and four (6.5%) patients had an atrial fibrillation recurrence. CONCLUSIONS: The vHPSD ablation represents an effective and safe ablation strategy to achieve bidirectional block for the treatment of typical AFL.