Predictors For Hyperperfusion Syndrome After Carotid Artery Stenting

Background and purpose Stroke has become the leading cause of adult disability, and is also the third largest cause of death after cardiovascular diseases and tumors at present. Eighty percent of the patients are ischemic stroke, and the remaining20percent are hemorrhagic stroke. The incidence of stroke is closely correlated to the degree of carotid stenosis. Around60%of patients with ischemic stroke have the ipsilatera lextracranial stenosis. When the medical treatment is not satisfied, carotid angioplasty and stenting (CAS) is an effective way to reduce the incidence of stroke owing to its advantages such as little trauma, rapid recovery and so on. Cerebral hyperperfusion syndrome (CHS), which is rare but serious postoperative complication of CAS, and even may lead to serious disability or death, has drawn wide attention. There is no consensus on the pathogenesis, definition, prevention and treatment. Our study aimed to discuss the risk factors for CHS in patients who underwent CAS.Methods We collected419cases of consecutive patients undergoing carotid stenosis line CAS from Nanjing Stroke Registry system (June,2005～June,2012). Clinical data of419patients who underwent467times of CAS (48of them were performed bilateral CAS) were retrospectively analyzed in this study. The patients were divided into hyperperfusion syndrome group (n=15) and non-hyperperfusion syndrome group (n=404).Results In the CHS group,2cases died of cerebral hemorrhage, two cases of subarachnoid hemorrhage were improved and discharged, two cases presented with focal neurological deficits, and10cases developed to headache, stretching and vomiting. Compared with non-CHS group, the proportion of patients with diabetes or postoperative hypertension were much higher in the CHS group (P<0.05, Table1). Among the15patients who occurred CHS,5cases had diabetes in which two developed to bad outcomes secondary to brain hemorrhage. Figure1provided the clinical image data of a typical case. There were no significant differences between the two groups with regard to characteristics such as age, sex, proportions, hyperlipidemia, smoking, stroke, heart disease, alcohol drinking, bilateral CAS, intraoperatively low hemodynamic response and ischemic events (P>0.05). The imaging feature of cerebral artery and perioperative data showed that:there were no differences between the CHS group and non-CHS group regarding the symptomatic lesions, dysplasia of A1segment of the anterior cerebral artery (ACA), patency of posterior communicating artery (PCoA), occlusion of middle cerebral artery (MCA), the extent of stenosis by the operated side either (P>0.05). Preoperative diabetes and postoperative hypertension were both correlated with CHS (P<0.05). In order to determine the predictors for postoperative CHS in patients received CAS, we found that, diabetes contributes the most after controlling for hypertension (Odds ratio=3.17,95%confidence interval [1.01-9.22], P=0.025). And hypertension was also a risk factor leading to CHS in patients who received treatment of diabetes preoperatively (Odds ratio=5.03,95%confidence interval [1.73-14.65], P=0.001).Conclusion Diabetes and hypertension are two major predictors for CHS after CAS.