Carotid web increases risk for recurrent stroke within 2 years of index event

One in six patients with a symptomatic carotid web experienced a recurrent stroke within 2 years of the index stroke, according to results of a cohort study of more than 3,400 patients with large vessel occlusion stroke.

The results indicate that “medical management alone may not provide sufficient protection for patients with [a carotid web],” according to the researchers. They described a carotid web as “a shelf-like lesion located along the posterior wall of the internal carotid artery bulb” that juts into the lumen of carotid artery, which can result in flow disruption and blood stasis, leading to thrombus formation and subsequent ischemic stroke.

“It is unclear how patients with a symptomatic [carotid web] (those who have had an ipsilateral ischemic stroke) are best treated to prevent recurrent stroke,” Valeria Guglielmi, MD, and colleagues wrote. “One of the major knowledge gaps in deciding the optimal treatment is the lack of studies on the risk of recurrent stroke in patients with a symptomatic [carotid web].”

Guglielmi, a member of the department of neurology at Amsterdam University Medical Center and the University of Amsterdam in the Netherlands, and colleagues conducted a comparative cohort study using data from the MR CLEAN trial, conducted from 2010 through 2014, and the MR CLEAN Registry, conducted from 2014 through 2017. These nationwide, multicenter, prospective studies examined endovascular treatment in patients with large vessel occlusion stroke in the Netherlands. Guglielmi and colleagues analyzed data in September 2020.

Neuroradiologists examined CT angiography images for the presence or absence of a carotid web. The incidence of a recurrent stroke within 2 years of the index stroke served as the primary outcome. Guglielmi and colleagues used Cox proportional hazards regression models to compare recurrent stroke rates within 2 years among patients with and without a carotid web, adjusting for age and sex.

The analysis included baseline data for 3,439 consecutive adult patients with anterior circulation large vessel occlusion stroke and CT angiography of the carotid bulb. The neuroradiologists identified 30 patients with carotid web ipsilateral to the index stroke, according to the study results. Guglielmi and colleagues then obtained “detailed follow-up data” regarding stroke recurrence within 2 years for those 30 patients and compared them with 168 patients in the MR CLEAN extended follow-up trial who did not have a carotid web and who were randomly assigned to the endovascular treatment arm.

The researchers reported a median age of 72 years (interquartile range [IQR], 61-80 years) and a slightly greater proportion of men (53%) in the group of 3,439 patients for whom baseline CT angiography assessments were available. Guglielmi and colleagues found that patients with a carotid web were younger (median age, 57 years [IQR, 46-66 years] vs. 66 years [IQR, 56-77 years]; P = .02) and were more likely to be women (73% vs. 40%; P = .001) than those without a carotid web.

Most patients (93%) received medical treatment following the index stroke, including 23 with antiplatelet therapy and five with anticoagulant therapy. Over the course of a 2-year follow-up period, five of 30 patients with a carotid web (17%) experienced a recurrent stroke, compared with five of 168 patients (3%) without a carotid web (adjusted HR = 4.9; 95% CI, 1.4-18.1). Patients with a carotid web experienced a longer time to recurrent stroke than those without a carotid web, according to the study results (6 months [IQR, 1-10 months] vs. 1 month [IQR, 0-7 months).

The researchers identified the location of the recurrent stroke in four of five patients with a carotid web, according to the study results, and found that these four recurrences were ischemic strokes in the same vascular territory as the carotid web. All five recurrent strokes in patients without a carotid web were ischemic, including two of which occurred in the same vascular territory as the index stroke. When the researchers limited the analysis to those with recurrent ischemic stroke ipsilateral to the index stroke, the risk increased eightfold in patients with an ipsilateral carotid web compared with patients without a carotid web (aHR, 8.1; 95% CI, 1.4-46.8). None of the patients with a carotid web contralateral to the index stroke experienced a recurrent stroke.

“This cohort study found that patients with a [carotid web] ipsilateral to the index stroke had a 5 times higher risk of recurrent stroke compared with patients without a [carotid web]. In absolute terms, 1 of 6 patients with a [carotid web] ipsilateral to the index stroke had a recurrent stroke within 2 years,” the researchers wrote. “Moreover, the recurrent ischemic strokes were in the same vascular territory as the [carotid web], and the risk of recurrent stroke appeared to persist after the 2-year follow-up period.”

Based on these findings, “prospective studies on targeted secondary prevention measures for patients with a [carotid web] are warranted,” according to Guglielmi and colleagues.