[A case of nonbacterial thrombotic endocarditis presenting positive findings by two-dimensional echocardiography]

A 55-year-old woman was admitted to our hospital because of left hemiparesis. Brain CT and cerebral angiography demonstrated cerebral embolism due to occlusion of the sphenoidal part of the right middle cerebral artery. Two-dimensional echocardiography revealed mitral valve vegetation measuring 10 x 7 mm and slight mitral-valve regurgitation. Blood cultures were negative. She developed disseminated intravascular coagulation. Chest roentgenography and abdominal ultrasonography showed multiple liver and lung tumors, but she died before the primary lesion was detected. At autopsy, adenocarcinoma of the gall bladder was found. Friable vegetation was attached to the auricular surface of the mitral valve. Microscopic examination confirmed the diagnosis of nonbacterial thrombotic endocarditis. Although echocardiography is an important tool for diagnosing nonbacterial thrombotic endocarditis, few reports have described echocardiographic detection of nonbacterial thrombotic endocarditis. Because vegetation of nonbacterial thrombotic endocarditis is smaller than that of infective endocarditis (less than 3 mm), it is difficult for echocardiography to detect nonbacterial thrombotic endocarditis. Thus, a negative examination does not exclude the possibility of nonbacterial thrombotic endocarditis. To make an antemortem diagnosis of nonbacterial thrombotic endocarditis, we must perform echocardiography carefully in cases of cerebral infarction with carcinoma and/or DIC.