Commissural fusion as etiology of bioprosthetic mitral stenosis in a patient with rheumatic heart disease.

We report commissural fusion as a unique morphologic etiology of early bioprosthetic mitral valve failure in a woman with a history of rheumatic mitral stenosis. She had undergone mitral valve replacement with a 25-mm Edwards Magna Ease bovine pericardial bioprosthesis 3 years earlier and presented with progressive dyspnea. Transesophageal echocardiography revealed severe bioprosthetic stenosis due to commissural fusion. She underwent percutaneous valve-in-valve implantation with a 26-mm Edwards Sapien 3 prosthesis. Marked symptomatic improvement was noted postprocedurally. We speculate that commissural fusion may be a unique pathologic feature of failing bioprosthetic valves in patients with prior rheumatic mitral valve disease.