Feasibility of percutaneous epicardial mapping and ablation for refractory atrial fibrillation: Insights into substrate and lesion transmurality

Epicardial recordings of Bachmann bundle activation during refractory mitral flutter with endocardial block

“…Our approach to epicardial mapping for refractory atrial fibrillation has been previously described. 1 Briefly, epicardial access was obtained prior to systemic heparinization and a steerable sheath was used to facilitate mapping of the posterior wall and sulcus between the left atrial appendage and left superior pulmonary vein. Activation mapping was performed of the clinical atrial flutter (tachycardia cycle length 360 ms), which indicated clockwise MAFL.…”

“…The left atrium is typically perceived as a thin-walled chamber without anatomic impediments to creating transmural ablation lesions. However, nontransmural lesions are a common cause of recurrent mitral annular atrial flutter (MAFL), 1 representing ablation gaps in 3-D (depth). Percutaneous epicardial mapping in the region of the Bachmann bundle (BB) may provide mechanistic evidence for the difficulties associated with creating durable anterior block for MAFL.…”

Outcomes of convergent atrial fibrillation ablation with continuous rhythm monitoring

“…Epicardial ablation with the EPi‐Sense device directs RF energy away from the esophagus and may mitigate the risk of atrioesophageal fistula. Additionally, dissociation between the endocardium and epicardium has been documented after endocardial PWI, 21 potentially mediated in part by epicardial connections from the septopulmonary bundle 22 . Delivery of RF directly to the epicardium may be better able to interrupt these epicardial connections and result in complete, transmural PWI.…”

“…Additionally, cardiac autonomic ganglia, which reside in epicardial fat pads, have been implicated in the pathogenesis of AF and may be more amenable to ablation from epicardial approaches 23 . It also should be noted that percutaneous mapping and ablation of the epicardium, via a subxiphoid approach similar to that used for epicardial ventricular arrhythmia ablation, is also feasible 21 . The relative benefits and risks of surgical versus percutaneous access to the epicardial space for AF ablation will require further study.…”

Residual potential at the epicardial left atrium after conventional left atrial posterior wall isolation for persistent atrial fibrillation: A case report

“…Some studies have reported that using an intrapericardial balloon and catheter for mechanical displacement of the esophagus enable safe ablation from the epicardium and increase chance of transmural isolation extending to the epicardium. 4,5 The contribution of transmural lesion formation to the prevention of AF recurrence is unclear and further study is needed.…”