Background and purpose: Cerebral infarction is the most frequent and severe manifestation of extracranial internal carotid artery dissection. However, few data exist on the precise time course of symptoms preceding the onset of stroke.
Methods: We studied 80 consecutive patients (29 retrospectively, 51 prospectively) with angiographically diagnosed extracranial internal carotid artery dissection and, during a 6-month follow-up, recorded the time elapsed between the onset of the first symptoms and the onset of any ischemic event (transient ischemic attack or stroke). We compared patients with and without ischemic events, with and without completed stroke, and, among patients who had local signs at onset, those with and without subsequent ischemic events.
Results: Cerebral or retinal infarction occurred in 42 patients. It was inaugural in 9 patients. In the 33 others, the time interval between the first symptoms (local signs and/or transient ischemic attacks) and the onset of stroke ranged from a few minutes to 31 days; it was < or = 7 days in 82% of the patients. No significant difference in the baseline characteristics of the patients or in the angiographic pattern of dissection was found based on the presence or absence of ischemic signs or of completed stroke.
Conclusions: In carotid artery dissections, completed stroke usually occurs in the first few days after the onset of the first symptoms, whether local or ischemic, but it can occur as much as 1 month later. This suggests that any potential preventive treatment should be initiated as early as possible after the onset of the first symptoms but might also be worth initiating even 1 month later.