Acute and long-term lesion durability and reconnection patterns following hybrid atrial fibrillation ablation

Abstract

Abstract Background/introduction Hybrid ablation (AF) is a well-established rhythm control strategy in non-paroxysmal AF patients and can be performed as a staged or one-step epicardial-endocardial approach. Data on need for endocardial touch-up acutely after epicardial ablation are limited, as well as long-term reconnection patterns in patients undergoing redo procedures. Purpose to evaluate the lesion transmurality detected via endocardial mapping acutely after epicardial radiofrequency (RF) ablation, as well as anatomical and clinical predictors of residual endocardial gaps in a large cohort of patients undergoing hybrid AF ablation. Furthermore, long-term lesion durability will be assessed in patients undergoing repeat endocardial ablation. Methods Hybrid procedures were performed in a one-step fashion (endocardial mapping +/- ablation immediately following left thoracoscopy epicardial ablation). Epicardial pulmonary vein (PV) isolation was achieved via a bipolar RF clamp; further epicardial linear ablation was performed with a RF bipolar linear device. Additional lesions were performed according to physician’s preference on a patient basis. At the end of the procedure, the left atrial appendage (LAA) was clipped. Results A total of 130 patients were included (mean age: 65±9.4; 72.3% males); among them, 19.2% and 55.4% had persistent or long-standing persistent AF. All patients received epicardial PV and posterior wall (PW) isolation plus additional RF applications to the LAA/posterolateral ridge. Other targets included the right inferior ganglionted plexus in 36.2% (n=47) and anterior mitral line (AML) in 3.8% (n=5). In 13.1% (n=17) epicardial lesions could not be completed due to difficult anatomy. At the end of the procedure, an attempt to clip the LAA was done in all patients, resulting in 97.7% success (3 LAA clip failures due to anatomical reasons). Acute endocardial mapping revealed a PV reconnection rate of 4.6% (n=24), left superior and right superior PVs being the veins most commonly reconnected (6.15% and 5.38%, respectively). PW and AML reconnections were documented in 8.5 % and 60% (3 out of 5 patients). Multivariate analysis showed left atrial (LA) volume and male gender as predictors for acute endocardial gaps after complete epicardial lesions. A redo procedure after first recurrence was performed in 24.6% (n=32), showing lesion durability of 100% for left PVs, 90.6% for right superior and 93.7% for right inferior PVs. PW remained isolated in 78.1% of patients. Age was a predictive factor for chronic gaps after recurrence. At a mean follow-up of 51±35 months, arrhythmia-free survival after multiple procedures was 68.5%. Conclusion In a large cohort of AF patients undergoing hybrid ablation,acute and chronic lesion durability was hight.LA volume and male gender were predictors of acute reconnection after epicardial ablation.