Spontaneous left atrial multiseptated intramural dissecting hematoma.

Our case was initially admitted with chest discomfort and congestive heart failure with a presumptive diagnosis of non-ST segment elevation myocardial infarction and was later found to have a large left atrial (LA) mass. In addition to a complete echocardiography study, multimodality imaging was utilized to better characterize the LA mass. Despite this, the diagnosis could not be confirmed. It was decided to proceed to cardiac surgery, and surprisingly, this revealed a large LA mass with pockets of fresh blood within the LA. Pathological specimen examination confirmed a diagnosis of thrombus, effectively outruling other atrial neoplasms. Although contrast echocardiography and cardiac magnetic resonance imaging suggested this diagnosis, in the absence of any predisposing factors, the final diagnosis was made at surgery and histopathological examination.