Abstract 17883: Subacute Native Aortic and Mitral Valve Endocarditis Manifesting as Embolic ST-Elevation Myocardial Infarction

Abstract

Case description: A 54-year-old male presented with one day of substernal chest pain. He also reported two months of malaise, myalgias, chills, and intermittent fevers. Medical history was notable for well-controlled hypertension and negative for dyslipidemia, diabetes, or drug and tobacco use. Family history was negative for premature coronary artery disease. Vitals were notable for fever of 103F, blood pressure of 108/56 mmHg, and heart rate of 88 beats per minute. Physical exam showed bounding pulses and a soft diastolic murmur at the left lower sternal border. Electrocardiogram showed inferior lead ST-elevations. He was taken for cardiac catheterization and found to have a totally occlusive thrombus in the distal right coronary artery with minimal disease in the remaining vessels. He underwent aspiration thrombectomy and placement of drug eluting stent with normal flow. He was transferred to the coronary intensive care unit. Labs showed mild leukocytosis, normal serum creatinine, and unremarkable urinalysis. Echocardiogram showed a 1.7 x 0.5 cm mobile echodensity on the aortic valve with severe aortic regurgitation and a small echodensity on the anterior mitral leaflet. Blood cultures grew Enterococcus faecalis. A CT scan of the head, chest, abdomen, and pelvis revealed no embolic disease. He underwent urgent surgery due to concern for infective endocarditis with coronary embolism. Purulence was found at the stent site and the posterior descending artery was obliterated by necrotic tissue. A bypass graft was placed distal to the stent site and infected territory was unroofed and irrigated. Mitral and aortic valve replacement was performed. He tolerated surgery and was discharged with 6 weeks of intravenous antibiotics. Discussion: This case was unique in the subacute chronicity of endocarditis and lack of other systemic emboli. Clinically relevant coronary embolism was reported in only 1.5% of cases of infective endocarditis but microemboli were found in 60% postmortem. Embolization is more common with mitral valve involvement, >10 mm vegetation, and fungal or staphylococcal disease. Angiographic evidence of heavy thrombus burden or lack of significant atherosclerosis after myocardial infarction may prompt evaluation for coronary embolism.