Mechanical Thrombectomy for Acute Medium Vessel Occlusion Because of Paradoxical Cerebral Embolism in a Patient with a Right Aortic Arch: A Case Report.

Abstract

Objective: Right aortic arch is a rare congenital anomaly. We report a case of mechanical thrombectomy for acute left medium-vessel occlusion due to a paradoxical embolism in a patient with a right aortic arch.

Case presentation: An 81-year-old woman presented with severe right-sided hemiparesis and aphasia. The National Institutes of Health Stroke Scale score was 16, MRI demonstrated a diffusion-weighted imaging Alberta Stroke Program Early CT score of 7, and MRA revealed left M2 occlusion. CTA revealed a right aortic arch with mirror image branching. Mechanical thrombectomy was conducted using the usual system, and effective recanalization was achieved with a stent retriever and aspiration catheter after 3 passes. CTA revealed pulmonary embolism and deep vein thrombosis (DVT) in the right deep femoral vein, and transesophageal echocardiography demonstrated a patent foramen ovale. Electrocardiography did not reveal atrial fibrillation, and other examinations did not reveal any other cause; therefore, a paradoxical cerebral embolism was diagnosed. After anticoagulant therapy, no recurrence of infarction, pulmonary embolism, or DVT was observed. Severe right hemiparesis and total aphasia did not improve, and the patient was discharged on day 37 after admission with a modified Rankin Scale score of 5.

Conclusion: Access to the left common carotid artery in right aortic arch cases can be anatomically challenging. Preoperative imaging evaluation of the access route is crucial for quick and safe mechanical thrombectomy.