Multimodality Imaging of a Very Large Mycotic Aneurysm of the Right Coronary Artery.

Abstract

February 2021 182 Mohamad Jihad Mansour , MD Vincent Mansourati, MD Matthias Richard, MD Ahmad Al Ayouby, MD Jacques Mansourati, MD Martine Gilard, MD Yannick Jobic , MD A 72-year-old man was admitted for oppressive acute chest pain. He had a medical history of moderate aortic stenosis and myocardial infarction treated by percutaneous coronary intervention. Two days before his admission, he was diagnosed with urinary tract infection with a urine culture positive for Staphylococcus aureus. On admission, his vital signs were normal except for low-grade fever of 38 °C. His ECG revealed anterolateral ST-segment elevation with reciprocal changes (Figure [A]). Bedside transthoracic echocardiography showed normal global left ventricular systolic function, moderate aortic stenosis (peak/mean gradients, 58 mm Hg/32 mm Hg; aortic valve area, 1.1 cm2; Figure [B]), and moderate-to-large pericardial effusion (Movies I and II in the Data Supplement; Figure [C]). Urgent cardiac catheterization was performed and showed an occluded mid left anterior descending artery lesion (Movie III in the Data Supplement) and an ulcerated nonobstructive plaque of the mid right coronary artery (RCA; Figure [D]; Movie IV in the Data Supplement). Immediate angioplasty with balloon inflation to the mid left anterior descending lesion showed residual impregnation. Stent crossing was not feasible due to severe coronary calcifications. Laboratory workup was remarkable for leucocytosis (12 g/L) and increased C-reactive protein at 35 mg/dL. The diagnosis of STsegment–elevation myocardial infarction complicated by acute pericarditis was initially retained. The patient remained febrile for 5 days despite the initiation of colchicine and cloxacillin in addition to aspirin. Ultrasound-guided pericardiocentesis drained 700 mL of hematic fluid with no residual effusion (Movie V in the Data Supplement). Blood cultures were positive for methicillin-sensitive S aureus. Transthoracic echocardiography and transesophageal echocardiography were repeated to rule out infective endocarditis (Movie VI in the Data Supplement) and identified the presence of an epicardial outpouching formation at the level of the right ventricle with a flow signal on color Doppler (Figure [E]; Movies VII through IX in the Data Supplement). Cardiac computed tomography confirmed the presence of a large outpouching formation of 35×40 mm arising from the RCA (Figure [H through J]). Cardiac positron emission tomography found intense 18F-fluorodeoxyglucose uptake of the lesion in favor of an active infectious or inflammatory process (Figure [F and G]). Those findings were consistent with an RCA mycotic aneurysm. As the patient remained febrile despite adequate antibiotherapy, the decision was taken to refer him to cardiac surgery. The aortic valve appeared severely calcified with a degenerative process, without any macroscopic findings consistent with infective endocarditis. He underwent uneventful surgical exclusion of the mycotic aneurysm (Figure [K]), bypass grafting of the RCA using a saphenous venous graft, bypass grafting of the mid left anterior descending using the left internal mammary artery, as well as bioprosthetic aortic valve replacement. At 10 days postoperatively, culture of © 2021 American Heart Association, Inc. CARDIOVASCULAR IMAGES