Dual antiplatelet therapy in acute aortic dissection of type A: a retrospective single-center study with propensity score matching analysis

Introduction: Acute aortic dissection of type A is a life-threatening condition where open surgical treatment is the "gold standard". The effect of prehospital double antiplatelet therapy (DAPT) on the results of surgical treatment has not been sufficiently studied. The available literature data indicate the ambiguity of the DAPT results in acute aortic syndrome. Objective: The study was aimed at assessing the effect of double antiplatelet therapy at the pre-hospital stage on the results of surgical treatment of acute aortic dissection type A. Methods: A retrospective analysis of the results of surgical treatment of patients with acute aortic dissection of type A was based on the patient database of Meshalkin National Medical Research Center. We analyzed 33 patients (DAPT group) who received double antiplatelet therapy at the pre-hospital stage and 63 patients (noDAPT group) without double antiplatelet therapy from non-matched cohort before the propensity score matching (PSM) analysis. After PSM analysis of the group, 29 pairs of patients were selected (a matched cohort). The primary endpoint was represented by a combination of events associated to bleeding, namely postoperative bleeding >1500 ml/12h, intraoperative wound tamponing and open bleeding revisions. Secondary, 30-day mortality, inhospital mortality and medium-term survival were evaluated before and after PSM analysis. The effect of preoperative DAPT on 30-day mortality was assessed using multivariate logistic regression analysis. Results: In the matched cohort, after PSM analysis for the primary endpoint, the distribution of patient between noDAPT and DAPT groups were 34.5% vs 51.7%, p = 0.210. In the DAPT group, fresh frozen plasma (p = 0.001) and red blood cell mass (p = 0.0009) were transfused significantly more frequently within 24 hours after surgery. There were no significant differences between the noDAPT and DAPT groups on indicators of 30-day mortality (10.3% vs 27.6%, p = 0.094) and 5-year survival (69% vs 60.9%, p = 0.357). In the multifactorial model of logistic regression analysis, DAPT was an independent predictor of 30-day mortality (OR 3.36 [95% CI, 1.02-11.04], p = 0.045); the combined primary endpoint, associated to bleeding indicators, increased its probability by 5 times (OR 4.98 [95% CI, 1.34-18.5], p = 0.016). Conclusion: Preoperative DAPT did not significantly increase either the incidence of bleeding-related events or the early mortality rate, and did not reduce mid-term survival in patients with acute type A aortic dissection. However, preoperative administration of DAPT was an independent predictor of 30-day mortality. Preoperative DAPT is not a limitation to surgical treatment of acute type A aortic dissection.