Influencing Factors for Abdominal Aortic Aneurysm Sac Shrinkage and Enlargement after EVAR: Clinical Reviews before Introduction of Preoperative Coil Embolization

Abstract

Background: We previously reported effectiveness of coil embolization (CE) to aortic branched vessels before endovascular aortic repair (EVAR) for abdominal aortic aneurysm (AAA) because of significant shrinkage of aneurysmal sac. In this study, we investigated EVAR cases to clarify influential factors of aneurysmal shrinkage and enlargement.Methods: 148 consecutive cases before the introduction of CE were retrospectively reviewed based on the presence of PT2EL (persistent type 2 endoleak) and change in sac diameter after EVAR by multivariate analysis.Results: (A) PT2EL risk factors were patent inferior mesenteric artery (IMA) and thinner mural thrombus inside aneurysmal sac. (B) Sac enlargement risk factors were antiplatelet intake, PT2EL, and female gender. (C) Sac shrinkage predictive factors were the absences of thoracic aortic aneurysm, antiplatelet intake, PT2EL, and coronary artery disease.Conclusion: CE to IMA was considered to be effective because patent IMA and antiplatelet intake were significant risk factors for sac enlargement. So, more meticulous therapeutic strategy, including treatment priority (AAA first or CAD first) and choice of treatment (EVAR vs. AAA) based on anatomical features of AAA was required to improve late outcomes.