A Systematic Review and Meta-Analysis of Determinants of Bowel Ischemia and Associated Risk After Elective Endovascular Abdominal Aortic Aneurysm Repair

Objective: Bowel ischemia (BI) is an uncommon but devastating complication of elective endovascular abdominal aortic aneurysm repair (EVAR). We performed a systematic review and meta-analysis to identify patient- and procedure-related risk factors for BI after elective EVAR. Methods: We searched PubMed, Embase, Scopus, Web of Science, Cumulative Index to Nursing and Allied Health Literature, Cochrane Library, Scielo, and Lilacs from database inception through March 31, 2024, without language or date restrictions. We included observational studies of adults who underwent elective EVAR and reported postoperative BI and extractable risk-factor data. Two reviewers independently screened titles, abstracts, and full texts, extracted data, and assessed study quality using the Newcastle-Ottawa Scale. For factors reported in multiple sufficiently homogeneous studies, random-effects meta-analysis was used to pool risk ratios (RRs) or mean differences (MDs), with heterogeneity assessed using I 2 . Results: Twenty-three retrospective cohort studies, including 306 344 elective EVAR procedures, met the inclusion criteria, and 10 provided sufficient data for quantitative synthesis. Across all studies, 1535 patients developed postoperative BI, corresponding to an overall incidence of approximately 0.5%. Female sex was associated with increased BI risk (RR, 2.66; 95% confidence interval [CI], 2.06-3.43; I 2 = 0%). Larger aneurysm diameter was also associated with increased risk (MD, 4.05 mm; 95% CI, 0.09-8.02; I 2 = 0%). Renal dysfunction was a consistent predictor, with chronic kidney disease (RR, 2.93; 95% CI, 1.01-8.47; I 2 = 29%) and dialysis dependence (RR, 5.35; 95% CI, 2.38-12.05; I 2 = 0%) associated with BI. Major intraoperative blood loss >1 L conferred the highest relative risk among pooled factors (RR, 7.45; 95% CI, 2.80-19.85; I 2 = 0%). Age, systemic arterial hypertension, and active smoking were not significantly associated with BI in pooled analyses. Conclusions: Bowel ischemia after elective EVAR is uncommon but clinically important because delayed recognition carries substantial morbidity and mortality. Female sex, larger aneurysm diameter, chronic kidney disease, dialysis dependence, and major blood loss identify patients who may warrant heightened perioperative vigilance. The certainty of evidence remains very low, and future studies should standardize reporting of bowel segment, mesenteric vessel involvement, inferior mesenteric artery and internal iliac artery status, endograft configuration, and overlapping registry populations. Clinical Relevance Bowel ischemia after elective endovascular abdominal aortic aneurysm repair (EVAR) is rare, but its low incidence should not be interpreted as low clinical importance because delayed diagnosis is often catastrophic. This systematic review and meta-analysis synthesizes the largest available elective EVAR evidence focused on bowel ischemia and identifies reproducible risk signals, including female sex, aneurysm size, renal dysfunction, dialysis dependence, and major blood loss. The practical gain for readers is not a definitive prediction score, but a clearer framework for perioperative judgment: recognize vulnerable patients, avoid overinterpreting weak or non-poolable associations, and apply heightened postoperative vigilance when embolic, hypoperfusion, pelvic collateral, or renal-risk features coexist.