Nonbacterial Thrombotic Endocarditis Resolved by Early Initiation of Anticoagulation Therapy and Surgical Intervention

Nonbacterial thrombotic endocarditis (NBTE) is a rare hypercoagulable condition, often associated with malignancy, sepsis, and autoimmune diseases, and carries a poor prognosis. This report presents a case of NBTE in the absence of an identifiable underlying disease, successfully treated with early anticoagulant therapy and surgical intervention. A 70-year-old male presented with a right upper extremity arterial occlusion and concomitant acute myocardial infarction. Transesophageal echocardiography revealed thrombus-like lesions in the left atrial appendage and aortic valve. With negative blood cultures and no clear etiology, NBTE was suspected based on systemic thromboembolic symptoms and echocardiographic findings. Anticoagulation therapy was initiated, followed by surgical removal of the left atrial appendage thrombus and coronary artery bypass grafting. Pathological examination confirmed the presence of sterile thrombi, consistent with NBTE. This case highlights the importance of considering NBTE in patients with multiple systemic emboli and negative blood cultures, even in the absence of an obvious underlying disease. It also emphasizes the benefits of prompt anticoagulant therapy and surgical intervention for improving patient outcomes.