Incidence and Risk Factors Associated with Index Hospitalization Leg Ischemia Following Endovascular Abdominal Aortic Aneurysm Repair.

Introduction / objectives: Although incidence of index hospitalization leg ischemia following abdominal aortic aneurysm repair is low (1-3%), it is a serious complication that deserves investigation. Pre-operative risk factors, such as demographics, medical history, and medication use (or lack of) that may be associated with this complication are understudied. Our aim is to predict the factors that may be associated with the development of leg ischemia following endovascular repair in the index hospitalization period.

Methods: All de-identified patient records from the Vascular Quality Initiative's abdominal aortic aneurysm endovascular repair registry (n=76,166) were examined from January 1, 2003 to June 1, 2023. Patients without leg ischemia (n=75,406) and those with it (n=760) during index hospitalization were separated into two groups. Demographic factors (e.g. sex assigned at birth), medical history (e.g. smoking status, hypertension), and medication use (e.g. statin use) were compared between the two groups utilizing univariate and multivariate analysis to examine association with leg ischemia. Comparisons with a p-value less than 0.05 were deemed significant.

Results: Over the study period, 1.0% of patients developed index hospitalization leg ischemia. Female sex assigned at birth (OR 1.76, 95% CI 1.40-2.20, p < 0.001), current smoking status (OR 1.72, 95% CI 1.20-2.46, p = 0.003), HTN (OR 1.61, 95% CI 1.16-2.22, p = 0.004), COPD (OR 1.29, 95% CI 1.04-1.61, p = 0.020), ruptured aneurysm (OR 2.06, 95% CI 1.52-2.80, p< 0.001), post-operative myocardial infarction (OR 2.06, 95% CI 1.24-3.45, p = 0.006), iliac artery adjunct procedure (OR 1.52, CI 1.16-1.99, p <0.002), iliac limb endpoint in external iliac artery (OR 2.56, CI 1.39-4.74, p <0.003), intraoperative iliac/femoral artery thrombectomy (OR 2.02, CI 1.15-3.56, p <0.015), and intraoperative distal embolectomy (OR 2.49, CI 1.29-4.81, p <0.007) were significantly associated with leg ischemia. Preoperative statin use (OR 0.79, 95% CI 0.59 - 0.92, p = 0.008) was significantly associated with decreased incidence of leg ischemia. Access site complications (hematoma / occlusion) had the largest impact (OR 18.65, 95% CI 14.49-24.00, p < 0.001) on the development of leg ischemia.

Conclusions: Certain factors such as female sex assigned at birth, current smoking status, ruptured aneurysm, iliac artery adjunct procedure, external iliac artery endpoint, and access site complication may be indicative of index post-operative leg ischemia. Preoperative statin may decrease risk of developing leg ischemia.