An 85-year-old woman who had undergone transcatheter aortic valve (TAV) implantation with a 23-mm SAPIEN XT (Edwards Lifesciences, Irvine, CA, USA) 7 years earlier was admitted with congestive heart failure. Transthoracic echocardiography showed severe structural valve deterioration, with a mean aortic valve pressure gradient of 52 mmHg, valve area of 0.66 cm², and moderate transvalvular regurgitation. Transesophageal echocardiography and computed tomography revealed no vegetation, thrombus, or frame recoil. TAV-in-TAV implantation using a 23-mm SAPIEN 3 Ultra RESILIA (S3UR) was successfully performed under local anesthesia. Two-year follow-up echocardiography demonstrated satisfactory hemodynamic results, with a mean gradient of 20 mmHg, valve area of 1.36 cm², and mild regurgitation. Although TAV-in-TAV is an established strategy for structural valve deterioration, data on S3UR implantation within a SAPIEN XT—particularly in small annuli—are limited. This case demonstrates its feasibility, but further studies are needed.

Toru Naganuma is an interventional cardiologist specializing in structural heart disease and complex cardiovascular interventions. He is currently working at New Tokyo Hospital in Japan. He completed his medical training at Yamaguchi University and has extensive experience in advanced catheter-based therapies. His clinical and research interests include Transcatheter Aortic Valve Replacement (TAVR), Mitral Transcatheter Edge-to-Edge Repair (TEER), Left Atrial Appendage Closure (LAAC), Atrial Septal Defect (ASD) closure, complex Percutaneous Coronary Intervention (PCI), and Endovascular Therapy (EVT). He is actively involved in clinical research and has presented his work at international conferences.