Early Surgical Intervention in Nonbacterial Thrombotic Endocarditis to Prevent Systemic Embolization

Aortic valve masses are rare and diagnostically challenging entities that may confer a significant risk of systemic embolization, particularly when large or highly mobile. We report the case of a 65-year-old woman who presented to an outside hospital with acute chest pain. Electrocardiogram demonstrated no ischemic changes, and serial cardiac troponins were negative. Transthoracic echocardiography revealed a large, mobile mass within the left ventricular outflow tract. Subsequent transesophageal echocardiography identified a 1.8-cm echogenic mass on the ventricular aspect of the aortic valve, prolapsing into the ascending aorta. An extensive infectious disease evaluation, including six sets of blood cultures, showed no evidence of infective endocarditis. Hematologic evaluation revealed a mildly elevated lupus anticoagulant, and perioperative anticoagulation with heparin was recommended, followed by rivaroxaban at discharge. Given the high embolic risk, surgical excision was pursued. Intraoperative cultures were negative, and histopathologic analysis demonstrated acellular fibrinous material. These findings were consistent with a diagnosis of nonbacterial thrombotic endocarditis (NBTE). NBTE is an uncommon condition typically associated with underlying hypercoagulable states and may closely mimic infective endocarditis in clinical and echocardiographic presentation. Early recognition of NBTE and a multidisciplinary approach involving cardiology, hematology, infectious disease, and cardiac surgery are essential to reduce embolic complications and optimize patient outcomes.