Mr. Q, a 50-year-old Caucasian, was referred for evaluation of fatigue that had begun three months earlier. During the past two weeks, he had also had low-grade fever and chills. Five months before his visit with us, he had undergone valve replacement for aortic stenosis associated with a congenital bicuspid aortic valve. His postoperative course was complicated by the development of complete heart block, for which he underwent placement of an atrioventricular sequential pacemaker.
1. EXAMINATION FINDINGS
Clinical examination revealed a temperature of 101°F and BP 130/60 mm Hg. On auscultation of the precordium, a prosthetic second heart sound with a grade 2/6 systolic murmur and a soft early diastolic murmur in the aortic area were heard.
Because of the patient’s surgical history, blood was drawn for cultures. Meanwhile, a transthoracic echocardiogram showed the presence of aortic regurgitation with a paravalvular leak. A transesophageal echocardiogram (TEE) revealed decreased mobility of the aortic disk valve and a mobile vegetation associated with an increased instantaneous peak gradient of 61 mm Hg. An aortic ring abscess was also observed.
Based on a working diagnosis of endocarditis, we started Mr. Q on empiric treatment with ceftriaxone and vancomycin. In order of frequency, the most likely causes of endocarditis are coagulase-negative staphylococci, Staphylococcus aureus, fastidious organisms responsible for culture-negative disease, and fungi. Other diagnostic possibilities being considered were infection of a pacemaker lead and sepsis due to unrelated causes, such as UTI or pneumonia.
Mr. Q soon developed signs of heart failure and was taken to the operating room for emergent valve replacement and debridement. The surgeon found a partial dehiscence of the valve along with an abscess cavity between the anterior mitral leaflet and the aortic root.