A multi-institutional study comparing antegrade and retrograde open mesenteric bypass for chronic mesenteric ischemia.

INTRODUCTION

Contemporary clinical practice guidelines recommend an endovascular-first approach for chronic mesenteric ischemia (CMI), reserving open mesenteric bypass (OMB) for flush ostial vessel occlusion, long-segment disease, heavily calcified lesions, or failed stents. However, guidelines are equivocal regarding bypass configuration, leaving the optimal strategy debated. The antegrade (AG) approach may carry higher perioperative risk due to supramesenteric aortic cross-clamping, whereas the retrograde (RG) approach from the infrarenal aorta or iliac vessels raises concerns about long-term patency. Therefore, we compared perioperative and midterm outcomes of AG and RG bypass in a multi-institutional cohort.

METHODS

We retrospectively reviewed consecutive patients undergoing OMB for CMI at two high-volume centers (2000-2024). The primary end point was 30-day mortality; secondary end points included complications, survival, and patency. Adjusted comparisons were performed using multivariable logistic regression, Cox models, and propensity-matched cohorts. Kaplan-Meier methods estimated survival and patency.

RESULTS

A total of 209 patients underwent OMB: 130 AG (all from center A) and 79 RG (36 from center A, 43 from center B). Compared with AG, RG patients had higher rates of cardiopulmonary comorbidity, including chronic obstructive pulmonary disease (57% vs 44%; P = .08) and congestive heart failure (26% vs 12%; P = .01), were more frequently transferred from other hospitals (29% vs 15%; P = .02), and more often received autogenous vein conduit (55% vs 1%; P < .0001). Unadjusted complication rates (22% vs 22%; P = 1), 30-day mortality (4.4% vs 8.7%; P = .3), and 90-day mortality (10% vs 15%; P = .5) were similar between groups. Primary patency was excellent and comparable (1-year: 97% ± 2% AG vs 98 ± 2% RG; 3-year: 90% ± 8% vs 90% ± 9%; P = NS). On multivariable analysis, bypass configuration was not independently associated with mortality (hazard ratio, 1.4; 95% confidence interval [CI], 0.7-2.7; P = .3) or perioperative complications (odds ratio, 0.93; 95% CI, 0.3-2.5; P = .9). In the propensity-matched cohort (65 AG vs 65 RG), early outcomes and patency remained similar; however, 1-year mortality was higher after RG bypass (36.8% vs 16.3%; odds ratio, 3.0; 95% CI, 1.2-8; P = .02). Overall survival in the full cohort did not differ significantly by Kaplan-Meier analysis (log-rank P = .5).

CONCLUSIONS

In this multi-institutional analysis of patients with CMI undergoing OMB, AG and RG configurations demonstrated similar perioperative morbidity and excellent graft patency. Bypass configuration was not independently associated with early or midterm outcomes in adjusted analyses, although higher 1-year mortality was observed after RG bypass in a propensity-matched cohort. These findings support individualized selection of bypass configuration based on anatomic considerations, conduit availability, patient comorbidity, and institutional expertise.