Successful typical atrial flutter ablation using a pentaspline PFA-catheter after TEER with a PASCAL device

Introduction: Pulsed-field ablation (PFA) is rapidly emerging as a valuable standard for pulmonary vein isolation (PVI). The pentaspline PFA catheter (FARAPULSE, Boston Scientific) is also gaining recognition for treating complex atrial tachycardias (AT), including both right and left-sided. However, the increasing number of devices and transcatheter interventions for tricuspid edge-to-edge repair (t-TEER) raises questions about the safety and feasibility of using the pentaspline PFA catheter after t-TEER. Furthermore, PFA for extra-PV targets is considered off-label due to the associated risks posed by proximity to critical anatomical structures in the right atrium. This is the first report of successful typical atrial flutter (AFL) ablation using the pentaspline PFA catheter after t-TEER with a PASCAL device for severe tricuspid regurgitation.

Case Description: An 83-year-old man with combined pre and post-capillary pulmonary hypertension and severe tricuspid regurgitation, previously treated with edge-to-edge leaflet repair using a PASCAL device, presented palpitations and worsening dyspnea due to typical AFL. Transthoracic echocardiography indicated a mildly reduced left ventricular ejection fraction and mild to moderate tricuspid regurgitation with a dilated right atrium. The patient also had highly symptomatic paroxysmal atrial fibrillation (AF). A combined PVI and cavotricuspid isthmus (CTI) ablation using the pentaspline FARAPULSE PFA catheter was selected for this patient. The baseline 12-lead ECG showed atrial flutter with a 3:1 conduction and a cycle length of 224 milliseconds. After PVI was successfully achieved, differential entrainment maneuvers confirmed the diagnosis of CTI-dependent AFL. Intravenous nitroglycerin was administered to prevent coronary artery spasm. The first train of pulses on the CTI terminated promptly the tachycardia, and a total of six applications ensured a complete CTI block without any dislodgement of the PASCAL system. The patient was discharged after two nights without complications.

Discussion:. Given its large footprint, CTI ablation using a pentaspline PFA-catheteter could potentially be more challenging and lead to device dislodgement. However,  in patients with significantly dilated right atria, often a consequence of valvular disease, its wide footprint may simultaneously provide procedural advantages as compared to a focal catheter. Our case demonstrates that CTI ablation with the pentaspline PFA-catheter could be both feasible and safe following t-TEER.  The growing use of t-TEER devices and the expanded application of the pentaspline PFA-catheter for extra-PV targets warrant further investigation into the safety, feasibility and efficacy of this approach.