Vascular Imaging Features and Time-Specific Recurrence Risk After Craniocervical Artery Dissection

Craniocervical artery dissection (CCAD) is a major cause of stroke in young adults, yet its recurrence risk remains poorly defined because of delayed enrollment in prior research. We aimed to determine the temporal distribution of recurrent ischemic stroke and evaluate whether dissection location or specific vascular morphologies are associated with recurrence risk across discrete time intervals after the index event.

This multicenter cohort study analyzed data from the nationwide CRCS-K-NIH registry in South Korea (2011-2021). We included adult patients with acute ischemic stroke or TIA and CCAD diagnosed within 7 days of symptom onset (median onset-to-arrival time, 7.7 hours). The primary outcome was 1-year recurrent ischemic stroke. Recurrent events required MRI confirmation of new or extending infarction. Location (intracranial [I-CCAD] vs extracranial [E-CCAD]) and morphology (angiographic subtypes and features such as double lumen) were evaluated across 4 intervals (≤1, 2-3, 4-7, and >7 days).

Among 75,903 hospitalized patients with acute ischemic stroke or TIA, 711 (0.94%) were diagnosed with CCAD. The mean age was 49.0 years, and 26.9% were women. I-CCAD accounted for 76.1% of cases. Recurrence was 8.7% on day 1, 17.4% within 1 week, and 19.9% at 1 year. Incidence rates declined steeply from 271.2 events per 1,000 person-days on day 1 to 0.1 beyond 7 days. Dissection location was not associated with recurrence risk. However, stenosis without dilatation (adjusted hazard ratio [aHR], 1.69 [95% CI 1.04-2.75]) and double lumen (aHR, 1.87 [95% CI 1.15-3.04]) were independently associated with higher 1-year recurrence risk. Double lumen sign was associated with recurrence between days 2 and 3 (adjusted incidence rate ratio, 3.84 [95% CI 1.67-8.81]).

Stroke recurrence after CCAD is strongly clustered in the hyperacute phase. Early recurrence risk appeared to vary according to vascular morphology rather than anatomical location, with the presence of a double lumen demonstrating a distinct early temporal recurrence pattern. These findings support morphology-based, time-specific risk characterization to inform monitoring and secondary prevention strategies. Limitations include the retrospective design and restriction to an East Asian population.