Unusual Cause of Stroke After Mitral Valve Replacement

A 78-year-old woman was admitted to the hospital because of ischemic stroke with regressive right hemiplegia. Two years earlier, she had undergone a supra-annular mitral valve replacement with a porcine bioprosthesis (St Jude Medical Epic No. 27, St. Jude Medical, Inc., St. Paul, Minn). Because of paroxysmal atrial fibrillation, she had received vitamin K antagonist treatment since the surgery. At admission, the patient was asymptomatic and had no fever. Physical examination revealed a 2/6 apical diastolic murmur.Transthoracic echocardiography performed at admission revealed several extensive vibratile masses attached to the prosthesis ring. Mean mitral gradient was 11 mm Hg, which indicated prosthesis obstruction. Maximal systolic pulmonary pressure was 47 mm Hg. Left ventricular ejection fraction was 50% as assessed by …