Heyde's syndrome: failure of a mechanical prosthesis and the possibility of a coagulation defect.

Recent data indicate that the gastrointestinal bleeding due to angiodysplasia associated with aortic stenosis (Heyde's syndrome) can be alleviated by aortic valve replacement with a bioprosthesis. This report details a situation in which valve replacement with a mechanical prosthesis and the subsequent anticoagulation promoted gastrointestinal bleeding from angiodysplastic lesions. Only when the mechanical prosthesis was replaced with a porcine prosthesis and the anticoagulation discontinued did the gastrointestinal bleeding stop.