Atrial Myxoma Presenting With Hemorrhage and Multifocal Infarcts in the Brain of a 59-Year-Old Man: An Uncommon Outcome for the Most Common Primary Heart Neoplasm.

Atrial myxomas are the most common primary neoplasm of the heart. Due to their mass effect, they may lead to dysfunction of the heart or mitral valve. Rarely, neoplastic fragments may embolize or a thrombus secondary to stasis may form, which can infarct downstream structures (e.g., the brain). We report the case of a 59-year-old man presenting with headaches, visual changes, and word-finding difficulty secondary to multifocal brain lesions that were identified on computed tomography and magnetic resonance imaging. After an extensive workup, the etiology of the patient's neurological symptoms was determined to be embolization from a large atrial myxoma (2.3x3.5 cm). Histologic and immunohistochemical examination of the atrial myxoma and largest brain lesion yielded similarities, including the presence of spindle-shaped and stellate cells, myxoid regions, Alcian blue pH 2.5 positivity, calretinin positivity, cluster of differentiation 34 (CD34) positivity, and cluster of differentiation 68 (CD68) negativity. This case was remarkable due to the patient's late presentation, the large size of the atrial myxoma, the presence of abundant cerebral hemisphere and cerebellar lesions, and the histologic comparison of the heart and brain lesions. Atrial myxomas have been reported from childhood to late adulthood and when symptoms typically present clinically due to the mass effect. However, neurologic manifestations from embolization or thrombus formation can occur, as in the present case. Therefore, considering the presence of atrial myxomas is important in patients with neurologic manifestations and heart murmurs.