Cerebrovascular fibromuscular dysplasia: The MGH cohort and literature review

BACKGROUND

Fibromuscular dysplasia (FMD) is a rare noninflammatory, nonatherosclerotic arteriopathy of medium-sized arteries affecting up to 7% of the population. The disease can affect any artery but commonly affects renal, extracranial carotid, and vertebral arteries. The epidemiology and natural course of cerebrovascular FMD is unknown and requires further investigation.

METHODS

We present demographic and outcomes data on a case series of 81 patients with cerebrovascular FMD from Massachusetts General Hospital presenting between 2011 and 2015 followed by a review of the peer-reviewed literature.

RESULTS

Patients were a median age of 53 years (±12 SD) and the majority were women. Approximately 50% had a history of tobacco use and more than two-thirds had hypertension. Most patients were on monoplatelet therapy with aspirin; during follow-up, 7 of 67 had progressive disease or additional symptoms. One of 67 patients had a cerebrovascular event: TIA. There were 5 of 67 who had noncerebrovascular events or disease progression and 1 death of unclear cause.

CONCLUSIONS

Cerebrovascular FMD may present with myriad symptoms. Our data support that patients with FMD with symptomatic disease have a low rate of recurrent symptoms or disease progression and can be managed conservatively with stroke risk modification, antiplatelet agents, surveillance imaging, and counseling.

A 10-year follow-up of extracranial-intracranial bypass for the treatment of bilateral giant internal carotid artery aneurysms in a patient with fibromuscular dysplasia: case report

Cervicocephalic fibromuscular dysplasia (FMD) is an idiopathic, non-inflammatory and non-atherosclerotic arteriopathy which usually affects small- and medium-sized cervical arteries distributed at the atlas and axis interspace. Few cervicocephalic FMD patients are associated with multiple intracranial aneurysms which may rupture or develop. So the authors describe a cervicocephalic FMD patient with a history of right oculomotor palsy in 2000. Angiography revealed bilateral internal carotid artery (ICA) aneurysms and a fusiform aneurysm in right vertebral artery. Typical "string-of-beads" phenomenon was observed in V2 segment of left vertebral artery. The right ICA giant aneurysm was treated by right ICA occlusion and superficial temporal artery (STA)-middle cerebral artery (MCA) bypass at that time. Five years later, the patient presented with paroxysmal weakness in right limbs. The subsequent angiography showed the enlargement of left ICA aneurysm. It was treated satisfactorily with left external carotid artery-saphenous vein-MCA bypass and left ICA ligation. During the long-term follow-up, the patient kept no neurological deficit and the angiography showed good patency of bilateral grafts and the lesions in bilateral vertebral arteries remained unchanged.

Fibromuscular Dysplasia of Cervical and Intracranial Arteries

Fibromuscular dysplasia is an uncommon, segmental, nonatherosclerotic arterial disease of unknown aetiology. The disease primarily affects women and involves intermediate-sized arteries in many areas of the body, including cervical and intracranial arteries. Although often asymptomatic, fibromuscular dysplasia can also be associated with spontaneous dissection, severe stenosis that compromises the distal circulation, or intracranial aneurysm, and is therefore responsible for cerebral ischaemia or subarachnoid haemorrhage. Fibro-muscular dysplasia affects middle and distal portions of the internal carotid and vertebral arteries, and occasionally, intracranial arteries. Several pathological and angiographic patterns exist. The most frequent pathological type is medial fibromuscular dysplasia, which is associated with the ‘string of beads' angiographic pattern. Unifocal lesions are less common and can be associated with several pathological subtypes. The pathophysiology of the disease is widely unknown. Fibromuscular dysplasia may in fact result from various causes and reflect a non-specific response to different insults. The poor knowledge of the natural history and the lack of randomised trials that compared the different treatment options do not allow any satisfactory judgement to be made regarding the need for or the efficacy of any treatment.

[Pediatric cerebrovascular accident secondary to fibromuscular dysplasia]

We present the case of a 13 year-old patient diagnosed with fibromuscular dysplasia (FMD) by angiographic study, with "string of beads" image of internal carotid, after undergoing two ischemic strokes in nine days. Conservative treatment with acetylsalicylic acid at antiaggregant doses was decided. Twenty months later the clinical progress is favorable without presenting any new episodes. FMD is a very uncommon cause of stroke in childhood. Little is known about its etiology. In spite of it usually being an asymptomatic disease, it must be considered in cases of repeated or inexplicable strokes. Its prognosis and treatment is controversial, due to the limited number of pediatric patients with this pathology.