PO-02-042 SAFETY AND EFFICACY OF VERY HIGH-POWER SHORT-DURATION TEMPERATURE-CONTROLLED ABLATION FOR THE TREATMENT OF PERSISTENT ATRIAL FIBRILLATION

Abstract

Ablation targets of persistent atrial fibrillation (AF) remain poorly understood nowadays: due to structural alterations of the left atrium, isolation of the pulmonary veins alone has proved ineffective. New ablation targets such as the posterior wall, coronary sinus, and left atrial appendage were then sought. A new catheter (QDOT Micro) has recently been released which has the potential to increase the safety and efficacy of the procedure: it is connected to a new radiofrequency (RF) generator which allows for temperature controlled ablation by reducing power and increasing irrigation with the increase in tissue temperature and allows to deliver power up to 90 W for few seconds (vHP-SD). Evaluate safety and efficacy of posterior wall vHP-SD ablation for patients with persistent AF We enrolled 29 patients treated with catheter ablation of persistent AF. Pulmonary vein isolation was performed in all patients. Substrate mapping of the posterior wall of the left atrium was subsequently performed in sinus rhythm with a multipolar catheter (Pentaray) and pathological potentials were eliminated with RF 90 W for 4 sec duration (vHP - SD). AF, atrial flutter and atrial tachycardia recurrences were identified by in office follow-up, 12-lead ECG, and dynamic Holter ECG. The treated patients have a median age of 63±10 years, 25 (86%) are male. Mean left atrial volume is 44.9 ± 17 ml/m2. 25 (86%) patients had never undergone catheter ablation before. Total mean procedure time is 75 ± 10 minutes, mean fluoroscopy time is 8 ± 5 minutes. Pulmonary veins isolation and posterior wall isolation was achieved in 100% of patients. There were no complications such as atrioesophageal fistula, phrenic nerve palsy, pericardial effusion and/or cardiac tamponade, pulmonary vein stenosis, or arteriovenous fistula. Patients free from arrhythmic recurrences are 69% after 8 months mean follow-up. The results demonstrated the clinical feasibility and safety of posterior wall vHPSD ablation for persistent AF using this new temperature-controlled catheter without intraprocedural and periprocedural complications at follow-up. However, this remains a single center experience in a small group of patients. Comparative trials involving greater number of patients with long-term follow-up are necessary to definitive results.