Recurrent nonbacterial thrombotic endocarditis the day after mitral valve replacement.

Nonbacterial thrombotic endocarditis (NBTE) is relatively rare, with an identification rate of 1.6% at autopsy, and is associated with malignancy and systemic lupus erythematosus. Further, bioprosthetic valve NBTE is extremely rare, with only a few reports in the literature. To ensure appropriate treatment, it is essential to differentiate between NBTE from infective endocarditis (IE) as soon as possible, but this is difficult without information regarding underlying disease and sufficient time for careful investigation. Here, we report a case of recurrent NBTE of a bioprosthetic valve the day following surgery based on an initial diagnosis of IE. < Nonbacterial thrombotic endocarditis (NBTE) is a relatively rare condition associated with some malignancies and systemic lupus erythematosus. Without information on underlying disease and sufficient time for detailed investigation, it is difficult to distinguish NBTE from infective endocarditis (IE). Unlike IE, the treatment strategy of NBTE involves initiating systemic heparinization as soon possible. This study suggests that NBTE should be considered in cases of recurrent cerebral embolism, even without information indicating underlying pathology.>.