Endocardial Vs Epicardial Ablation for Recurrent Paroxysmal AF

In these redo ablation patients, the ideal re-ablation strategy is unknown and many techniques have been proposed but there is no consensus nor strong clinical trial data. This treatment gap prompted the development of a combined minimally invasive epicardial and endocardial ablation ("Convergent") procedure. During the last decade, this "hybrid" approach has garnered increasing acceptance in clinical practice, with several reports of promising antiarrhythmic outcomes in challenging disease states, as well as modifications to maximize safety and clinical outcomes. One key aspect of this approach is that it targets key drivers of AF including the PVs but also the left atrial posterior wall (LAPW), combining endocardial and epicardial energy delivery. The LAPW (or "PV myocardium") shares similar embryological origins and electrophysiological properties with the PVs, is predisposed to develop fibrosis, and thus recognized as an important source of AF. Recently, the CONVERGE randomized clinical trial demonstrated superiority of this hybrid approach compared to PVI in patients with persistent AF. The left atrial appendage (LAA) has also been designated as a potential important trigger site of AF, and if isolated, may result in improved post-ablation AF outcomes. Although catheter-based isolation is controversial due to the potential to increase the risk of stroke, surgical exclusion of the LAA by placement of an occlusive clip has been suggested to be both antiarrhythmic and anti-thrombotic. Thus it is proposed in this trial to incorporate the LAA clip within the hybrid procedure. Given the sheer volume of patients undergoing ablation of AF and the predictable necessity to perform repeat ablation procedures on a portion of these patients, the need for a proven redo ablation strategy is self-evident. The investigators thus propose a randomized clinical trial to determine if there is incremental efficacy by performing LAPW/LAA isolation via a hybrid approach in comparison to the conventional redo PVI alone in patients with paroxysmal AF.