Predictors of 1-Year Survival After Endovascular Aneurysm Repair

Abstract

Objective/background: The purpose of this study was to determine the preoperative variables that best predict 1-year survival following elective endovascular aneurysm repair (EVAR), a period of time that would suggest the patient had benefited from the procedure. Most EVAR survival studies focus on early and late survival; scant information is available for 1-year survival.

Methods: Data from two Australian audits of EVAR (1999-2001 and 2009-13) were combined (n = 1,647). Preoperative variables included routine demographic data, clinical health assessments, computed tomography-derived anatomical data, and all-cause mortality. Univariate and multivariate logistic regressions determined which variables best predicted 1-year survival.

Results: One-year survival after EVAR was 93.7% (1,544/1,647) and 30-day survival was 98.4% (1,620/1,647). Univariate analyses found that nine preoperative variables were significantly associated with 1-year survival. Five variables were included in the final multivariate model: American Society of Anesthesiologists physical status, aneurysm diameter, creatinine, respiratory assessment, and severity of iliac artery calcification (receiver-operator curve 0.717, R(2) = .117). Predicted 1-year survival ranged from 98.6% to 68.0%, based on differences in aneurysm size and patient comorbidities.

Conclusion: Personalised 1-year survival risk enables surgeons and patients to consider seriously the risks and benefits of EVAR prior to surgery.

Keywords: Abdominal aortic aneurysm; Endovascular procedures; Mortality.