ABSTRACT
We report a case of redo mitral valve replacement (MVR) for a Björk-Shiley Delrin valve implanted 47 years previously. A 71-year-old man initially underwent MVR for mitral regurgitation at our hospital at the age of 16 years. Following the operation, follow-up examinations were performed at the outpatient clinic and annual transthoracic echocardiogram findings showed only mild mitral regurgitation, with no adverse events noted. However, a transthoracic echocardiogram examination performed 45 years after the operation revealed mild to moderate mitral regurgitation, while dyspnea with exertion was also noted at that time. As part of a more detailed examination, transesophageal echocardiogram results showed moderate transvalvular leakage. Redo MVR was subsequently performed under the diagnosis of prosthetic valve dysfunction. Analysis of the explanted prosthetic valve revealed wear of the Delrin disk, and widening of the gap between the disk and strut, which were presumed to be the cause of transvalvular leakage. A half century has passed since introduction of the Björk-Shiley valve and the present is a rare case of valve malfunction. Presented here are related details, along with a review of existing literature and results of Björk-Shiley valve use at our hospital.