Triple-Valve Nonbacterial Thrombotic Endocarditis Associated With Malignancy: A Rare Clinical Presentation.

Nonbacterial thrombotic endocarditis (NBTE) is a rare form of endocarditis characterized by sterile vegetations, typically affecting the mitral or aortic valves. It is most commonly associated with hypercoagulable states, secondary to malignancy or systemic inflammatory disease. The condition itself is often asymptomatic and is frequently diagnosed when patients present with signs of systemic embolization. Heart failure is an uncommon initial presentation, and cases involving multiple valves are rare. This report describes the case of a 57-year-old man who presented with progressive dyspnea and signs of cardiac failure. Imaging revealed a pulmonary embolism and a mass in the left lateral segment of the liver, suggestive of cholangiocarcinoma. The patient exhibited features of a hypercoagulable state, including two prior admissions for lower limb deep vein thromboses and signs of peripheral cutaneous ischemia. Transesophageal echocardiography (TEE) identified vegetations affecting the mitral, tricuspid, and aortic valves, each associated with severe regurgitation. In the context of malignancy and persistently negative blood cultures, a diagnosis of NBTE involving all three valves was made. This case represents one of the rare instances of NBTE simultaneously involving the mitral, tricuspid, and aortic valves. While NBTE typically affects the left side of the heart, right-sided valve involvement is rare, and pulmonary embolism and heart failure are uncommon presenting features. This case underscores the importance of maintaining a high index of suspicion for NBTE in patients with malignancy who present with embolic events, new murmurs, or signs of heart failure.