ABO-blood groups and outcomes after abdominal aortic aneurysm repair.

ObjectivesTo analyze the association between blood groups (ABO and Rh) and long-term outcomes following abdominal aortic aneurysm (AAA) repair.MethodsRetrospective cohort study including all patients submitted to elective AAA surgery between 2009 and 2019. Outcomes were mortality and major adverse cardiac events (MACE).ResultsOf the 333 patients included in this study, 49.5% had blood type A, followed by 39.3% with type O, 8.1% with type B and 3.1% with type AB. Regarding Rh factor, 82.4% were Rh⁺ and 17.6% were Rh^-. The distribution of the blood phenotypes was similar between AAA patients and the Portuguese population. The median follow-up time was 75.4 months (interquartile range 65.8-81.6). Patient survival rates at 1 and 5 years were 89.3% (95% Confidence Interval 86.0-92.7) and 61.9% (56.2-68.2), respectively. MACE-free survival at 1 and 5 years was 85.7% (81.9-89.5) and 57.6% (51.9-64.0), respectively. Survival and MACE-free survival rates were similar across blood group types. Age, maximum aortic diameter, peripheral arterial disease and chronic obstructive pulmonary disease were independent predictors of mortality. Maximum aortic diameter, estimated glomerular filtration rate, cerebrovascular disease and type of surgery were independent predictors of MACE.ConclusionWe found no association between the blood types and the prevalence of AAA or adverse outcomes following AAA repair.