Electrophysiological findings in patients with isolated veins after cryoablation for paroxysmal atrial fibrillation.

AIMS: The main cause of atrial fibrillation recurrence after catheter ablation is pulmonary vein reconnection. The purpose of this retrospective study was to analyse the electophysiological findings in patients undergoing repeat procedures after an index cryoballoon ablation (CB-A) and presenting with permanency of pulmonary vein isolation (PVI) in all veins. In addition, we sought to compare the latter with a similar group of patients with reconnected veins at the redo procedure. METHODS: A total of 132 patients (81 men, 60.7 ±â€Š12.4 years) who underwent CB-A for paroxysmal atrial fibrillation (PAF) were enrolled. Indication for the redo procedure was symptomatic PAF in 83 (63%), persistent atrial fibrillation (PerAF) in 32 (24%) or persistent regular atrial tachycardia (RAT) in 17 (13%) patients. RESULTS: Seventy-five (57%) patients presented a pulmonary vein reconnection (pulmonary vein group) during the redo procedure, whereas 57 (43%) had no pulmonary vein reconnection (non-pulmonary vein group). The non-pulmonary vein group exhibited significantly more non-pulmonary vein foci and atrial flutters than the pulmonary vein group after induction protocol (51 vs. 24%, P = 0.002 and 67 vs. 36%, P = 0.003, respectively). Twenty-two (29.3%) patients of the pulmonary vein group and 20 (35%) patients of the non-pulmonary vein group had atrial fibrillation/RAT recurrence after a mean follow-up of 12.5 ±â€Š8 months. The survival analysis demonstrated no statistical significance in recurrence between both groups (log rank P = 0.358). CONCLUSION: Atrial fibrillation/RAT recurrence in patients after CB-A with durable PVI is significantly associated with non-pulmonary vein foci and atrial flutters. No statistically different success rate regarding atrial fibrillation/RAT freedom was detected between the pulmonary vein and non-pulmonary vein groups after redoing RF-CA.

Hybrid thoracoscopic epicardial ablation of right ventricular outflow tract in patients with Brugada syndrome.

BACKGROUND: Abnormal delayed electrograms (EGMs) from the anterior wall of the right ventricular outflow tract (RVOT) epicardium have become the ablation target in Brugada syndrome (BrS). OBJECTIVE: The aim of this study was to analyze the safety, feasibility, and efficacy of a novel hybrid thoracoscopic approach to perform epicardial RVOT radiofrequency ablation in BrS. METHODS: Thirty-six patients with BrS (26 men (72.2%); mean age 36.6±15.8 years; range 3-63 years) who underwent hybrid thoracoscopic epicardial ablation of RVOT from January 2016 to April 2018 were included in this study. Two expert electrophysiologists analyzed the EGMs during ajmaline challenge and guided the surgeon to perform ablation. Ajmaline challenge was repeated after 1 month to assess the absence of the BrS electrocardiographic pattern. Patients were followed by remote monitoring and outpatient visits every 6 months. RESULTS: The elimination of all abnormal EGMs was achieved in 94.4% of patients. After a mean follow-up of 16 ± 8 months (range 6-30 months), freedom from ventricular arrhythmias was obtained in 7 (77.8%) patients in secondary prevention 9/36 (25%) and in 24 (100%) patients in primary prevention 24/36 (75%). Major complications were observed in 1 patient (2.8%), who experienced late cardiac tamponade. CONCLUSION: Hybrid thoracoscopic epicardial RVOT ablation in BrS is a safe and feasible approach, allowing direct visualization of ablation during radiofrequency delivery. Because of ventricular arrhythmia recurrences, implantable cardioverter-defibrillator implantation is still mandatory in patients treated in secondary prevention and with high risk.