Endovascular Repair And Conservative Treatment Of Acute Uncomplicated Stanford Type B Aortic Dissection

Background: The long-term efficacy of best medical treatment(BMT)in patients with acute uncomplicated Stanford type B aortic dissection is not ideal.Thoracic endovascular aortic repair(TEVAR)has begun to be used for preventive treatment of uncomplicated Stanford type B aortic dissection,but there are few studies comparing the efficacy of TEVAR and BMT in the treatment of acute uncomplicated Stanford type B aortic dissection.Objective: To evaluate the early and mid-long-term effects of TEVAR and BMT in patients with acute uncomplicated Stanford type B aortic dissection.Methods: The clinical and imaging data of 357 patients with acute uncomplicated Stanford type B aortic dissection admitted from February 2008 to March 2018 in Wuhan Union Hospital of Tongji Medical College of Huazhong University of Science and Technology were retrospectively analyzed.According to the treatment method,these patients were divided into two groups with 191 cases in the TEVAR group and 166 cases in the BMT group.After propensity score matching,we obtained 145 matched patients for subsequent analysis.Study endpoints included early(in-hospital / 30 days)and late mortality(including all-cause and aortic-related mortality),adverse events(including aortic rupture,retrograde type A aortic dissection,endoleak,and new dissection)incidence and late intervention rate.Kaplan-Meier survival analysis was used to calculate early and late mortality;a competing risk model(using all-cause death as a competing event)was used to calculate the cumulative incidence of late adverse events and late intervention;and the risk factors that was associated with all-cause death were analyzed by univariable and multivariate Cox proportional hazard regression models.Results: After matching,there was no significant difference in baseline data between the two groups of patients.Among the matched populations,there was no statistically significant difference in early mortality between the TEVAR group and the BMT group,while the incidence of early adverse events was significantly higher in the TEVAR group than in the BMT group(P = 0.003).The 1,3,and 5-year all-cause mortality in the TEVAR group were 2.8%,3.6%,and 8.1%,and the 1,3,and 5-year all-cause mortality in the BMT group were 5.8%,11.5%,and 17.8%,respectively.All-cause mortality at 1,3,and 5-year was significantly higher in the BMT group than in the TEVAR group(P = 0.028).The 1,3,and 5-year aortic-related mortality in the TEVAR group were 2.2%,2.8%,and 5.9%,and the 1,3,and 5-year aortic-related mortality in the BMT group were 5.8%,9.8%,and 13.9%.The aortic-related mortality at 1,3,and 5-year was significantly higher in the BMT group than in the TEVAR group(P = 0.044).Multivariate Cox proportional hazard regression model analysis showed that the older(HR,1.04;95% CI,1.01-1.08,P = 0.013),BMT(HR,2.33;95% CI,1.08-5.05,P = 0.032),the distance between the primary entry tear and the left subclavian artery(LSA)<2.0 cm(HR,2.30;95% CI,1.06-4.99,P = 0.035)was a significant risk factor for allcause death.Using death as a competing factor and conducting a competing risk analysis,the results showed that the cumulative incidence of rupture was significantly higher in the BMT group than in the TEVAR group(BMT: 13.7% for 5 years,TEVAR: 5.1% for 5 years,P = 0.024).There was no statistically significant difference between the group in the incidence of cumulative retrograde type A aortic dissection,cumulative new dissection,and cumulative late intervention.Conclusion: Although TEVAR has more early complications than BMT,it reduces the risk of late death and aortic rupture in patients with acute uncomplicated Stanford type B aortic dissection.Therefore,TEVAR may be considered as the first option to improve the middle to late prognosis in patients with acute uncomplicated Stanford type B aortic dissection.