ObjectiveTo determine the clinical efficacy of transapical transcatheter mitral valve-in-valve treatment for patients with deteriorated mitral bioprosthesis after aortic-mitral double valve replacement.MethodsThe clinical data of 9 patients who underwent transapical transcatheter mitral valve-in-valve implantation after aortic-mitral double valve replacement due to mitral bioprosthesis deterioration from May 2020 to January 2021 in our hospital were retrospectively analyzed, including 4 males and 5 females with a mean age of 72.44±7.57 years.ResultsSurgeries were performed successfully in all patients with no conversion to median sternotomy. The mean procedural time was 101.33±48.49 min, the mechanical ventilation time was 23.11±26.54 h, the ICU stay was 1.89±1.05 d and the postoperative hospital stay was 6.11±2.02 d. Residual mild mitral regurgitation was only observed in 1 patient. Only 1 patient needed postoperative blood transfusion. No major complications were observed in all patients. There was no death in postoperative 90 days.ConclusionFor patients with deteriorated mitral bioprosthesis after aortic-mitral double valve replacement, transapical transcatheter mitral valve-in-valve implantation achieves good clinical results and effectively improves the hemodynamics without increasing the risk of postoperative left ventricular outflow tract obstruction. The surgery is feasible and effective.