External coronary artery compression due to prosthetic valve bacterial endocarditis.

Acute coronary syndromes in the setting of infective endocarditis may be the result of coronary compression secondary to periannular aortic valve complications, coronary embolism, obstruction of the coronary ostium due to a large vegetation, coronary atherosclerosis, and severe aortic insufficiency. External coronary artery compression as a result of infective endocarditis is a rare and lethal finding with few reported cases available in the medical literature. We present a rare occurrence of an acute coronary syndrome occurring in the setting of a bioprosthetic aortic valve abscess in which there was no complete coronary occlusion visualized and given the patient's recent unremarkable catheterization and findings of diffuse tapering of the proximal left coronary system, the most likely etiology was external compression secondary to the known aortic root abscess, which caused myocardial ischemia, and was confirmed during surgery. Although uncommon, external compression should be considered in the differential diagnosis of acute coronary syndrome in this setting and coronary angiography can be diagnostic of this entity.