Objective:To explore the diagnosis and clinical characteristics of multi-slice spiral computed tomography angiography(MSCTA)on acute aortic syndrome(AAS).Methods:A total of 185 patients with suspected AAS who were treated in Fuyang People's Hospital from June 2020 to July 2022 were selected,and the diagnostic results of digital vascular subtraction(DSA)were taken as the"gold standard".Before confirmation,MSCT plain scan and MSCTA examination were conducted,and the positively and negatively predictive values of MSCT plain scan and MSCTA were calculated by using four-cell table method.The area under curve(AUC)values,sensitivities and specificities of MSCT plain scan and MSCTA in diagnosing AAS were analyzed by using receiver operating characteristic(ROC)curve model.Results:As the gold standard of DSA diagnostic results,82 cases of 185 patients with suspected AAS were confirmed as AAS.The positively and negatively predictive values of MSCT plain scan were 68.35%and 73.58%,respectively.The positively and negatively predictive value of MSCTA examination were 96.30%and 96.15%,respectively.The diagnostic accuracy of MSCTA was significantly higher than that of MSCT plain scan(x2=42.092,P<0.05).The detection rates of laceration locations(ascending aorta,aortic arch and descending aorta)in MSCTA were significantly higher than that in MSCT plain scan(x2=6.788,4.000,12.974,P<0.05),respectively.ROC curve analysis showed that the AUC values of MSCT plain scan and MSCTA were respectively 0.698 and 0.946 in diagnosing AAS.Conclusion:MSCTA has a higher efficiency in diagnosing AAS,and AAS mostly includes the aortic dissection separation and aortic intramural hematoma.