Computed tomography angiography findings predict the risk factors for preoperative acute ischaemic stroke in patients with acute type A aortic dissection

OBJECTIVES: Acute ischaemic stroke (AIS) is a highly dreaded complication of acute type A aortic dissection (ATAAD). Knowledge about independent predictors of preoperative AIS in patients with ATAAD remains unclear. The aim of this study was to identify the risk factors for preoperative AIS in patients with ATAAD by computed tomography angiography (CTA) findings. METHODS: Between October 2014 and March 2017, 281 (217 male; mean age, 50years) patients with ATAAD underwent aortic CTA and diffusion-weighted magnetic resonance imaging of the brain was used to confirm the results. The clinical data and CTA findings were evaluated retrospectively. Patients were divided into 2 groups depending on the presence or absence of preoperative AIS. RESULTS: Preoperative AIS was detected in 103 (36.7%) of the patients with ATAAD. Univariable analysis of the clinical characteristics and CTA findings revealed that age, aortic valve insufficiency (moderate or severe), the ratio of the diameter of the true lumen of the ascending aorta to the diameter of the involved ascending aorta, intimal flap plaque, dissection of the common carotid artery (CCA), the lower density of the unilateral internal carotid artery, the CCA originating from the false lumen and dissection of the subclavian artery were implicated in patients with ATAAD with AIS. Multivariable analysis further showed that aortic valve insufficiency (moderate or severe) [odds ratio (OR) 2.033, 95% confidence interval (CI) 1.052-3.931; P=0.035], 2 CTA findings including the ratio of the diameters (OR 0.074, 95% CI 0.011-0.516; P=0.009) and dissection of the CCA (OR 2.422, 95% CI 1.389-4.224; P=0.002) were independent risk predictors for preoperative AIS in patients with ATAAD. The lower density in the false lumen, the same enhancement in the true and false lumen with re-entry and the stenosis of the true lumen without re-entry significantly increased the risk of preoperative AIS in CCA dissection. CONCLUSIONS: Aortic valve insufficiency (moderate or severe), the ratio of the diameters of the true and false lumens and CCA dissection are independent predictors of preoperative AIS in patients with ATAAD. The specific carotid and aortic CTA findings may help to predict the risk factors for preoperative AIS in patients with ATAAD.