What factors counteract mid-term survival following endovascular repair of abdominal aortic aneurysms?

Introduction
Endovascular aortic aneurysm repair (EVAR) for abdominal aortic aneurysm (AAA) is increasingly used, and has become the standard treatment option for AAA.

Aim
To evaluate the outcomes and predictors of survival of endovascular treatment of AAA in the short- and medium-term.

Material and methods
A total of 222 patients having endovascular AAA repair between January 2013 and December 2019 by the same surgical team were included in the study. Patient demographics, perioperative and follow-up data including mortality, complications, and need for secondary intervention were collected. The primary endpoint was all-cause mortality. Kaplan-Meier analysis was conducted for survival and Cox regression models were assessed for predictors of survival.

Results
The median age was 70 years, with male predominance (202 patients, 91%). Thirty-day mortality was 1.8%. Median follow-up to the primary endpoint was 20 months (range: 1–80 months). Survival rates at 1, 3, and 5 years were 93.5%, 81.4%, and 62.2%, respectively. Freedom from secondary intervention rates were 95.5% at 1 year, 88.7% at 3 years, and 82.1% at 5 years. Cox proportional hazard models showed that preoperative creatinine levels ≥ 1.8 mg/dl (hazard ratio (HR) = 2.68, 95% CI: 1.21–6.42, p = 0.027), haemoglobin levels < 10 gr/dl (HR = 3.38, 95% CI: 1.16–9.90, p = 0.026), ejection fraction < 30% (HR = 5.67, 95% CI: 1.29–24.86, p = 0.021), and AAA diameter ≥ 6.0 cm (HR = 2.20, 95% CI: 1.01–4.81, p = 0.049) were independently associated with mid-term survival.

Conclusions
EVAR is a safe procedure with low postoperative morbidity and mortality. This study confirms that the mid-term survival and results are favourable. However, the analysed factors in this study that predict reduced survival (high preoperative creatinine, low haemoglobin, low ejection fraction and larger aneurysms) should be judged when planning endovascular repair of AAA.