Mobile caseous mitral annular calcification as a cause of recurrent cardioembolic stroke: a case report.

Background: Caseous mitral annular calcification (CMAC) is a rare variant of mitral annular calcification that may occasionally lead to systemic embolization. Case Summary: We report the case of a 68-year-old woman with cardiovascular risk factors and a heterozygous factor V Leiden mutation presenting with recurrent embolic strokes. Initial investigations in 2021 revealed a posterior mitral annular mass with central echolucency on transoesophageal echocardiography, consistent with CMAC, associated with a small thrombus. Anticoagulation was initiated, and serial imaging demonstrated a stable lesion over several years. In 2025, the patient developed recurrent multifocal cerebral infarctions. Repeat imaging showed progression of the mass with a newly mobile atrial component, indicating high embolic risk. Multimodality imaging, including echocardiography and cardiac computed tomography, confirmed the diagnosis and excluded differential diagnoses such as tumour or infective endocarditis. The patient underwent mitral valve replacement with complete resection of the lesion. Histopathological examination showed signs of advanced CMAC. Postoperative recovery was uneventful, with no recurrence of embolic events. Discussion: This case highlights the dynamic nature of CMAC and underscores the importance of close follow-up and timely surgical intervention in the presence of recurrent embolization or high-risk structural abnormalities.