Intracranial Vessel Stenosis in a Young Patient with an MYH11 Mutation: A Case Report and Review of 2 Prior Cases.

Abstract

The MYH11 gene codes for smooth muscle myosin heavy chain, which has a critical function in maintaining vascular wall stability. Patients with this mutation most commonly have aortic and cardiac defects. Documented involvement of intracranial vessels is exceptional. A 29-year-old woman with a history of patent ductus arteriosus and aortic dissection was found to have incidental bilateral stenosis of the terminal internal carotid arteries as well as the proximal anterior cerebral arteries, middle cerebral arteries, and posterior cerebral arteries on magnetic resonance angiography that was obtained for unrelated symptoms. There was no evidence of basal collateral formation, and a generalized straightening of the vessels was observed. These angiographic findings have been typically observed in patients with ACTA2 mutations. Thus, genetic testing was pursued, which uncovered the presence of an MYH11 mutation. Follow-up imaging at 51 months demonstrated that the intracranial stenosis remained stable without evidence of basal collateral formation. She did not experience any neurologic events during the follow-up interval. Intracranial vessel involvement in patients with MYH11 mutations is rare. Vigilant cerebrovascular monitoring should be practiced in this population to guide appropriate management. Reporting of similar cases is important to improve understanding of the development of idiopathic intracranial stenosis in young individuals.