Cryptogenic stroke caused by thrombus in a left-sided atrial septal pouch in an otherwise healthy woman

A 46-year-old woman was admitted with sudden-onset dysarthria, left-sided weakness, and left facial droop.By the time emergency medical services arrived, her neurological deficits had begun to improve.Non-contrast head computed tomography showed a hyperdense focus, and computed tomography angiography demonstrated absent contrast filling in the right middle cerebral artery (M1/M2 segments), consistent with large-vessel occlusion.Mechanical thrombectomy was performed, and a 25 mm thrombus was retrieved and recanalization was achieved.