When a Hypersomnolent Hemodialyzed Patient Actually Has a Rare Stroke: A Case of Artery of Percheron Infarction With Paradoxical Embolism.

Introduction: Artery of Percheron (AOP) is an uncommon anatomic variant of the arterial supply of the medial thalami. Owing to variable clinical presentation, challenging imaging diagnosis, and its rarity, it is difficult to diagnose AOP infarctions. We present a clinical case of a unique presentation of AOP infarction associated with paradoxical embolism and highlight the atypical clinical manifestations and challenging diagnosis of this stroke syndrome.

Case report: A 58-year-old White female with chronic renal insufficiency on hemodialysis was admitted to our center with a 10-hour course of hypersomnolence and right-sided ataxia. She had normal body temperature, blood pressure, peripheral oxygen saturation, and heart rate and scored 11 points in the Glasgow Coma Scale and 12 points in National Institutes of Health Stroke Scale. Initial brain computerized tomography scan, electrocardiogram, and thoracic radiography were normal; transcranial Doppler ultrasound showed >50% stenosis at the P2 segment of the right posterior cerebral artery, and transthoracic echocardiogram, a patent foramen ovale and thrombus adherent to the hemodialysis catheter. On day 3, she underwent brain magnetic resonance that showed acute ischemic lesions at the paramedian thalami and the superior cerebral peduncles. AOP infarction due to a paradoxical embolism from a patent foramen ovale with a right atrial thrombus was the final diagnosis.

Conclusions: AOP infarctions are a rare type of stroke with elusive clinical presentations and frequently, initial imaging assessment is normal. Early recognition is crucial, and a high index of suspicion is needed to suspect this diagnosis.