Survival despite almost complete occlusion by chronic thrombosis of a Björk-Shiley mitral prosthesis

We report a patient who was successfully reoperated because of almost complete thrombosis of a Björk-Shiley tilting disc mitral prosthesis. Considering the usually acute presentation and the frequently catastrophic consequences of most similar cases in the literature, the unusual feature of this case is that the patient survived until reoperation with minimal symptoms despite almost total prosthetic occlusion by a chronic thrombus.