The natural history of carotid fibromuscular dysplasia.

Although graduated internal dilatation has proved to be an effective, safe, and durable operation for the treatment of symptomatic patients with fibromuscular dysplasia of the extracranial internal carotid artery, the role of surgical treatment in this entity remains unclear because the natural history is not well defined. Forty-nine patients, aged 29 to 82 years (mean, 58.5 years), with angiographically proven fibromuscular dysplasia of 88 internal carotid arteries have been evaluated since 1969. Twenty patients showed symptoms of focal cerebral or retinal ischemia, 10 patients had nonlateralizing neurologic symptoms, three patients sustained intracerebral hemorrhage, five patients complained of nonischemic symptoms, and 11 patients were asymptomatic. The three patients with intracranial hemorrhage and one person who suffered a massive stroke after angiography died within weeks of admission; no surgical therapy was performed. Initial management of the other patients included four internal carotid endarterectomies in four patients for associated atherosclerosis, one with simultaneous graduated internal dilatation; seven graduated internal dilatations in five patients; and one extracranial-to-intracranial bypass in a patient with occlusion occurring after graduated internal dilatation. Seventy-three nondilated arteries in 42 patients have been followed for up to 16 years (mean, 6.8 years). During this time only three patients have undergone surgical therapy; one carotid endarterectomy was done for an asymptomatic atherosclerotic lesion and two graduated internal dilatations in patients with nonfocal ischemia. Through follow-up of all 49 patients, none has had a new neurologic deficit. Fourteen patients who initially presented with focal ischemia were not treated surgically and all but one are now asymptomatic.(ABSTRACT TRUNCATED AT 250 WORDS)