Risk factors for postoperative mortality in patients with type A aortic dissection

Abstract

Introduction. Acute aortic syndrome is one of the most severe conditions in cardiac surgery: in case of type A dissection, up to a quarter of patients die within the first day and up to 75% within 14 days if not opertated, and hospital mortality after surgery varies from 12 to 50%. Objective. To identify perioperative risk factors of 30-day mortality in patients with acute type A aortic dissection. Methods. Retrospective cohort study. The end point of the study was 30-day and 5-year overall mortality. Patients operated on between 2018 and 2023 were studied. The patients were operated under extracorporeal circulation, hypothermia and selective antegrade cerebral perfusion if indicated. Parametric and nonparametric methods were used for statistical processing, including ROC-analysis and Kaplan-Meier method. Intergroup endpoints were compared using the log-rank test. Univariate and multivariate regression analysis was used to assess risk factors for 30-day mortality, and Cox proportional hazards regression was used to evaluate midterm mortality. Results. Sixty eligible patients were included. 85% of patients had distal anastomoses in zone 0, 10% in zone 1, and 5% in zone 2. The 30-day mortality rate was 30% and the 5-year mortality rate was 50%. When examining risk factors for 30-day mortality, the Charlson index (OR 3.0802; 95% CI 1.3048–7.2713; p=0.0103) preoperative platelet concentration (OR 0.9682; 95% CI 0.9388–0.9986; p=0.0404) and hemoglobin concentration in the first postoperative blood test (OR 0.8470; 95% CI 0.7352–0.9758; p=0.0215) demonstrated statistical significance. The following factors influenced midterm mortality according to Cox proportional hazards regression: Charlson index (HR 2.1782; 95% CI 1.4870–3.1907; p=0.0001), preoperative trombocyte concentration (HR 0.9874; 95% CI 0.9784–0.9965; p=0.0067), duration of extracorporeal circulation (HR 1.0304; 95% CI 1.0054–1.0560; p=0.0168), hemoglobin concentration in the first postoperative blood test (HR 0.9441; 95% CI 0.9164–0.9727; p=0.0002), aortic dissection type II vs. I (HR 0.104; 95% CI 0.0213–0.5083; p=0.0052). Conclusions. Several groups of predictors of early andьшвterm mortality were obtained: laboratory (preoperative platelet and postoperative hemoglobin levels), surgical (type of dissection and duration of extracorporeal circulation) and general (Charlson comorbidity index) predictors.