One-year outcomes of endovascular aneurysm repair in high-risk patients using the endurant stent-graft: Comparison of the ASA classification and SVS/AAVS medical comorbidity grading system for the prediction of mortality and adverse events

Purpose: To evaluate the outcome and survival of patients with extensive comorbid conditions after endovascular aneurysm repair (EVAR) and objectify which of 2 medical comorbidity classifications is more accurate in predicting adverse outcomes. Methods: All 1263 patients (mean age 73.1 years; 1129 men) treated using the Endurant Stent Graft system and entered in the prospective global postmarketing ENGAGE registry (ClinicalTrials.gov identifier NCT00870051) were grouped using the American Society of Anesthesiologists (ASA) classification and the Society for Vascular Surgery/ American Association for Vascular Surgery (SVS/AAVS) medical comorbidity grading system. Patients assigned to ASA III and IV and SVS/AAVS 2 and 3 categories were considered high risk. Primary outcome was 1-year all-cause mortality. Secondary outcomes included technical and clinical success, major adverse events (MAE), aneurysm rupture, endoleaks, and secondary endovascular procedures. One-year follow-up of the entire ENGAGE cohort was the endpoint of the study. Results: A total of 1263 patients were included. The overall technical success rate was high, the lowest being 97.4% in the ASA I group. The overall 30-day and 1-year Kaplan-Meier survival estimates were 98.7% and 92.5%, respectively. All cause 1-year mortality was higher in the ASA III and IV groups, but this did not reach statistical significance (5.2% and 5.7% for ASA I and II vs 9.0% and 9.9% for ASA III and IV, p=0.12). In the SVS/AAVS groups, 1-year all-cause mortality significantly increased with the SVS/AAVS score to 11.3% in the SVS/AAVS 3 group (p=0.002). There were significantly more MAEs in the SVS/AAVS 3 group at 1 year (p<0.001 for group 1 vs 3 and group 2 vs 3). Conclusion: Endovascular aneurysm repair has evolved, and high technical success and low mortality and morbidity can be achieved in high-risk patients. When treating high-risk patients, the perioperative risks should always be weighed against the expected gains. In contrast to the ASA classification, the SVS/AAVS medical comorbidity grading system is a useful tool to predict occurrence of MAEs and 1-year survival in patients undergoing EVAR.