A Word of Caution: Aorto-Right Ventricular Fistula, an Uncommon Pitfall of Perceval Sutureless Valve

Background: An aorto-right ventricular fistula (ARVF) secondary to membranous septum rupture is an exceptionally rare complication after surgical aortic valve replacement (SAVR). While sutureless prostheses such as the Perceval valve have gained wide acceptance due to reduced cross-clamp times and procedural simplification, the reported adverse events predominantly include conduction disturbances and paravalvular leaks. Structural septal disruption remains sparsely described. We report a case of an early ARVF after Perceval implantation and review the pathophysiological and procedural mechanisms implicated in septal injury following sutureless and transcatheter aortic valve interventions. Case Description: A 66-year-old woman with severe bicuspid aortic valve stenosis underwent SAVR via a median sternotomy using a Perceval XL prosthesis after meticulous annular decalcification and sizing. Immediate intraoperative transesophageal echocardiography (TEE) confirmed optimal seating without any paravalvular regurgitation. Within 24 h, the patient developed a complete atrioventricular block followed by cardiogenic shock. A repeat TEE revealed a large ARVF with significant left-to-right shunt. Emergent re-exploration identified a membranous septum tear. The Perceval prosthesis was explanted, the defect was closed with a reinforced patch repair, and a 27 mm Inspiris Resilia bioprosthesis was implanted. Peripheral veno-arterial ECMO support was required temporarily. The patient recovered and remained free of prosthetic dysfunction at the two-year follow-up. Discussion: Membranous septum rupture after AVR has an estimated incidence of 0.4–1.5% in TAVR cohorts but is virtually unreported with Perceval valves. The mechanisms are thought to be chronic radial stress from oversized or malpositioned prostheses. Case reports with TAVR devices emphasize oversizing as a risk factor. Predictive factors for septal injury in sutureless AVR mirror those for conduction disturbances: valve oversizing, shallow infra-annular septal length, heavy calcification, and prior valve surgery. Preventive measures, such as strict sizing protocols, the avoidance of balloon dilation, and optimized implantation depth, have reduced conduction complications and may mitigate septal trauma. The treatment choice, whether percutaneous or surgical closure, depends on hemodynamic stability, defect size and anatomy, and operative risk. Conclusions: Early ARVF after Perceval implantation is exceedingly rare but potentially catastrophic. Strict adherence to sizing principles, awareness of septal anatomy, and prompt management, percutaneous in selected stable cases or surgical in acute large defects, are essential to optimize outcomes in sutureless AVR.