Transapical transcatheter mitral valve implantation in a patient with mitral annular defect due to a patch dehiscence after aortic valve replacement: a case report

Transcatheter mitral valve implantation (TMVI) has emerged as a therapeutic option for high-risk patients with severe mitral regurgitation (MR) who are unsuitable for surgery. The Tendyne system, with its dual-frame design consisting of an atrial cuff and an external frame, has shown promising in complex anatomical settings. However, experience with Tendyne TMVI remains limited in patients with post-surgical MR caused by mitral leaflet perforation and a concomitant mechanical aortic valve prosthesis.

An 80-year-old woman with a prior mechanical aortic valve replacement (St. Jude Medical, 21 mm) for bicuspid aortic stenosis presented with severe mixed MR. At the index operation, a Manouguian aortic root enlargement using a pericardial patch had been performed to prevent prosthesis-patient mismatch. During follow-up, patch dehiscence resulted in perforation of the anterior mitral leaflet, while concomitant annular dilatation generated an additional regurgitant jet, resulting in severe mixed MR. Given the prohibitive risk of redo cardiac surgery (EuroSCORE II 25.24%), the multidisciplinary Heart Team recommended a transcatheter treatment strategy. Following Heart Team evaluation, transapical TMVI with a Tendyne prosthesis (29S LP) was performed. The procedure achieved complete elimination of MR without residual paravalvular leak or interference with the mechanical aortic valve. Notably, the external stent frame of the prosthesis successfully sealed the mitral leaflet perforation, eliminating the need for additional closure devices.

This case underscores the importance of imaging-guided, multidisciplinary Heart Team planning in optimizing procedural outcomes for patients with challenging post-surgical anatomy. Transcatheter mitral valve implantation might be a feasible option for patients with MR after cardiac surgery at prohibitive surgical risk.