Association of Carotid and Vetebral Arterial Variations with Risk of Ischemic Stroke

Abstract

Abstract Background With the wide application of computed tomography angiography (CTA), it is found that carotid and vertebral arterial variation has a high incidence in ischemic stroke. The aim of our study was to investigate the relationship between carotid and vertebral artery variants and the risk of ischemic stroke through a prospective and large sample study. Methods Carotid and vertebral arterial variations in consecutive subjects were prospectively studied using CTA. Variations of the carotid and vertebral arteries were classified into tortuosity, kinking and coiling using the criteria established by Weibel and Fields. Tortuosity is defined as a non-rectilinear stretch of an artery with an angulation > 90–165°. Kinking is described as an acute angle between two arterial segments ≤ 90°. Coiling is defined as a 360°. We analyzed the association between arterial variations and the risk of stroke using multivariate Cox proportional-hazards models. Results A total of 29319 subjects aged 50 years or older (14391 males and 14928 females) were examined for carotid and vertebral arterial variations. Among all subjects who completed the five-year follow-up, 1841 (6.3%) cases of stroke were detected. The proportion of kinking and coiling in the carotid and vertebral arteries in subjects with stroke was higher than that in subjects without stroke. Following adjustments for potential confounders, kinking and coiling of the carotid artery were significantly associated with stroke risk (HR = 1.47; 95% CI 1.32 to 1.64; P < 0.001), and kinking and coiling of the vertebral artery were also significantly associated with stroke risk (HR = 1.36; 95% CI 1.22 to 1.51; P < 0.001). Conclusions The results of the current study indicate that kinking and coiling in the carotid and vertebral arterial variations are associated with a significantly increased risk of ischemic stroke.