A structured pre-procedural risk mitigation strategy for ultra-high-risk TAVR in a nonagenarian with extreme aortic valve calcification: a case report using a balloon-expandable valve and proactive ECMO backup

Transcatheter aortic valve replacement (TAVR) in nonagenarians with extensive aortic valve calcification is associated with a substantial risk of intraprocedural circulatory collapse. This case report describes a structured pre-procedural risk mitigation strategy integrating a balloon-expandable valve system and a pre-emptive, “wet-prepared” extracorporeal membrane oxygenation (ECMO) backup. A 97-year-old man with severe symptomatic aortic stenosis (peak velocity = 4.76 m/s; aortic valve calcium volume = 1178 mm³) underwent transfemoral TAVR using a structured approach incorporating precision imaging, careful device selection using a domestic Chinese balloon-expandable valve system (Prizvalve ® TAV23), proactive ECMO preparedness, and multidisciplinary team coordination. Immediately after valve deployment, the patient developed circulatory collapse (blood pressure = 40/20 mmHg). A predefined emergency protocol was promptly activated. Following chest compressions, vasopressor administration, and pacing optimization, spontaneous circulation was restored within minutes. Angiography confirmed stable valve positioning with satisfactory expansion. At 3-month follow-up, echocardiography demonstrated absence of paravalvular leakage and preserved left ventricular systolic function. This case demonstrates the feasibility of a structured, pre-procedural risk mitigation strategy for TAVR in an exceptionally high-risk patient. The approach enabled the management of intraprocedural circulatory collapse. In this setting, the balloon-expandable valve platform demonstrated procedural characteristics that were well suited for this complex anatomy.