Bioprosthetic Aortic Valve Infective Endocarditis

Abstract

A woman in her late 50s was admitted to the hospital with a 4-week history of persistent mild cough, intermittent fever and chills, and generalized fatigue. Her past medical history includes hypertension, dyslipidemia, and rheumatic fever as a child with resultant mitral sclerosis and aortic stenosis. Past surgical history includes appendectomy, tonsillectomy, left mastectomy, and a Toronto stentless aortic valve replacement in 2002. Two weeks prior to admission, she had a hypotensive episode considered related to recurrent fever and dehydration.On physical examination, her temperature was 101°F and blood pressure was 107/52. Her weight was stable at 108 pounds. She appeared mildly ill but not in acute distress. Her heart rate was regular at 88, and respirations were 16. Auscultation of the heart revealed a 3/6 systolic ejection murmur heard best at the apex with radiation to the neck. Electrocardiogram demonstrated an old left bundle branch block. Chest X-ray was unremarkable.Infective endocarditis of the aortic valve usually presents with vegetations attached to the ventricular surface of the valve. Vegetations can be large, pedunculated, and freely mobile, making the risk of embolization high. The author reports a case of bioprosthetic aortic valve endocarditis caused by the rare organism Cardiobacterium hominis with an atypical presentation of the vegetation on the aortic surface.