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Recurrent spontaneous cervical-artery dissection.

BACKGROUND
Spontaneous dissection of the internal carotid and vertebral arteries is increasingly recognized as a cause of ischemic stroke in young people. An underlying arteriopathy is often suspected in the pathogenesis of such dissection, but the frequency of recurrent dissection is unknown.


METHODS
We describe the long-term follow-up of 200 consecutive patients (104 women and 96 men) with spontaneous cervical-artery dissections evaluated at the Mayo Clinic between 1970 and 1990. All diagnoses were confirmed by angiography.


RESULTS
The mean age of the patients was 44.9 years (range, 16 to 76). Internal carotid arteries were affected in 150 patients, vertebral arteries in 37, and both in 13. Multivessel dissections were present in 28 percent of the patients. The mean follow-up was 7.4 years. Recurrent dissection occurred only in arteries not previously involved by dissection. A recurrent arterial dissection developed in 16 patients (8 percent)--within a month after the initial dissection in 4 patients (2 percent) and between 1.4 and 8.6 years later in 12 patients (a rate of 1 percent per year). The cumulative rate of recurrent dissection among patients followed for 10 years was 11.9 percent. Younger patients had a greater risk of recurrent dissection.


CONCLUSIONS
Although dissections in multiple cervical vessels are common at presentation, after the first month the risk of recurrent dissection is only about 1 percent per year.