Neurologic sequelae of unilateral carotid artery occlusion: immediate and late.

Over a 7-year period (1980 to 1987) 24 patients (18 men: mean age 67 years; range, 52 to 78 years, and six women: mean age 67 years; range, 46 to 82 years) undergoing serial carotid artery duplex scans were observed to progress to unilateral carotid artery occlusion. The occlusions were associated with ipsilateral strokes in six (25%), ipsilateral transient ischemic attacks in four (16%), and the onset of nonhemispheric symptoms in one (5%). Thirteen patients had no symptoms. Follow-up ranged from 4 months to 96 months (mean 39.4 months). Late neurologic events comprised two strokes, three transient ischemic attacks and the onset of nonhemispheric symptoms in six, which in some were disabling. Thirteen patients had no symptoms. Three deaths occurred (one was stroke related). For late events by life-table analysis, the average annual rate over the first 2 years for stroke was 10% and for transient ischemic attack 13%. The combined rate for transient ischemic attack and stroke was 20% per annum. For nonhemispheric symptoms the rate for the first year was 31%. It is concluded that unilateral carotid artery occlusion is associated with an unacceptable incidence of immediate neurologic sequelae and that such patients continue to have a high rate of late neurologic deficits at follow-up. Therefore it seems appropriate that patients who are observed to progress to high-grade stenosis and are therefore at risk for immediate occlusion should undergo prophylactic carotid endarterectomy.