Cerebral arteriopathy in ACTA2 mutations: a spectrum of disease highlighted by a case of variable penetrance in two siblings

Clinical and neuroimaging features of a familial pathogenic ACTA2 variant as a model of a vascular neurocristopathy

The clinical and neuroimaging findings of a family with a variant ACTA2 gene (c351C > G), presenting with smooth muscle dysfunction in structures of neural crest derivation, are discussed. The combination of aortic abnormalities, patent ductus arteriosus, congenital mydriasis and distinctive cerebrovascular and brain morphological abnormalities characterise this disorder. Two sisters, heterozygous for the variant, and their mother, a mosaic, are presented. Brain parenchymal changes are detailed for the first time in a non-Arg179His variant. Radiological features of the petrous canal and external carotid are highlighted. We explore the potential underlying biological and embryological mechanisms.

Nonsurgical treatment of cerebral ischemia associated with ACTA2 cerebral arteriopathy: a case report and literature review

Mutations in ACTA2 gene can lead to multisystemic smooth muscle dysfunction, including cerebrovascular disease. Treatment strategies for this rare entity remain controversial, and patients are at increasing risk of neurological sequelae. We herein present the case of an 11-year-old boy previously diagnosed with an ACTA2 gene mutation who developed repetitive transient ischemic attacks and treated with bosentan, an oral endothelin receptor antagonist. Magnetic resonance imaging revealed bilateral, periventricular white matter T2 hyperintensities, and magnetic resonance angiography identified several abnormalities including fusiform dilatation in the proximal segments of internal cerebral arteries, together with followed by terminal segmental stenosis. The distal branches showed a markedly straightened course with no increase in lenticulostriate collaterals. Magnetic resonance imaging also revealed an increase in the number and size of large periventricular white matter lesions located in the left frontal lobe with the progression of ischemic symptoms. Instead of revascularization surgery, the administration of bosentan was started due to the high risk of perioperative ischemic sequelae. After bosentan initiation, the patient's repetitive episodes of cerebral ischemia ceased, and there has been no increase in the number of white matter lesions for 7 years. Bosentan might be beneficial for treating cerebral ischemia associated with ACTA2 cerebral arteriopathy by maintaining the dilatation of stenotic vessels and adequate systemic blood flow and should be considered before performing revascularization surgery.