A meta-analysis of the results of open surgical repair of infrarenal, juxtarenal and type IV thoracoabdominal aneurysms

Objective To evaluate the impact of proximal versus infrarenal aortic cross-clamping on perioperative outcomes during open abdominal aortic aneurysm (AAA) repair. Methods Article screening was conducted using Medline, Embase, and the Cochrane databases. The primary outcome was 30-day mortality; secondary outcomes included cardiac, renal, pulmonary, gastrointestinal, cerebrovascular, and wound complications, reintervention, dialysis and hospital length of stay. End points were compared using risk ratio (RR) for binary outcomes and mean difference for continuous outcomes. For all outcomes, 95% confidence intervals were calculated. Subgroup analysis was done for supraceliac and suprarenal clamp groups. A trial sequential analysis was done for the primary outcome. Meta-regression was conducted for all covariates with at least 10 observations. Heterogeneity was assessed through the I 2 statistic. GRADE assessment of the findings was performed. Results Fifteen studies comprising 13,140 patients were included. Infrarenal clamping was associated with significantly lower 30-day mortality (RR 2.26; 95% CI 1.32–3.89; p=.003), reduced renal complications (RR 2.57; 95% CI 2.03–3.26; p < .0001), permanent dialysis, myocardial infarction, arrhythmia, pulmonary complications, and reintervention, and shorter hospital stay. No differences were found for cerebrovascular, gastrointestinal, or wound complications. Subgroup analysis indicated that excess mortality was primarily driven by supraceliac clamping. Conclusion Infrarenal aortic clamping during open AAA repair confers superior perioperative outcomes compared with proximal clamping. When technically feasible, the lowest possible clamp level should be chosen to minimize renal and cardiac morbidity and improve early postoperative survival.