An Unusual Case of Nonbacterial Thrombotic Endocarditis Attributable to Malignancy

Nonbacterial thrombotic endocarditis (NBTE), also known as marantic endocarditis, is a condition characterized by the deposition of thrombi and fibrin on normal or degenerated cardiac valves in the absence of microorganisms. We report a case of a 60-year-old male with nonbacterial thrombotic endocarditis found on transesophageal echocardiogram (TEE) after a normal TEE just one month prior. Our patient presented with abdominal pain associated with poor appetite and unintentional 20-pound weight loss for one month. Chest computed tomography revealed the presence of a mass-like opacification in the right lung middle lobe with moderate pericardial effusions. A biopsy of the mass confirmed malignancy consistent with lung primary adenocarcinoma. Subsequently, during hospitalization, the patient developed left lower extremity pain. Arterial ultrasound showed occlusion of the distal left popliteal artery for which he underwent thrombectomy of the left superficial femoral artery, balloon angioplasty of the left posterior tibial artery, and left popliteal artery. Repeat TEE during current hospitalization revealed a large 2 cm vegetation on the noncoronary cusp of the aortic valve. Studies for infective endocarditis were unremarkable. Subsequently, he was treated with aortic valve replacement and anticoagulation. After discharge, he returned with bilateral occipital infarcts four days later and expired.