Comparative Outcomes of Open Mesenteric Bypass after a Failed Endovascular or Open Mesenteric Revascularization for Chronic Mesenteric Ischemia
Abstract
INTRODUCTION: Clinical practice guidelines have recommended an endovascular-first approach(ENDO) for management of patients with chronic mesenteric ischemia(CMI) while open mesenteric bypass(OMB) is proposed for subjects deemed to be poor ENDO candidates. However, the impact of a previous failed endovascular or open mesenteric reconstruction on subsequent OMB is unknown. Accordingly, this study was designed to examine the results of a remedial OMB(R-OMB) after a failed ENDO or primary OMB(P-OMB) for patients with recurrent CMI. METHODS: All patients undergoing OMB from 2002-2022 at the University of Florida were reviewed. Outcomes after R-OMB(i.e., history of failed ENDO or P-OMB) and P-OMB were compared. The primary end-point was 30-day mortality while secondary outcomes included complications, re-intervention, and survival. Kaplan-Meier methodology was used to estimate freedom from re-intervention and all-cause mortality while multivariable Cox proportional hazards modeling identified predictors of death. RESULTS: A total of 145 OMB procedures(R-OMB, n=48[33%]; P-OMB, n=97[67%]) were analyzed. A majority of R-OMB operations were performed for a failed stent(prior ENDO, n=39[81%]; prior OMB, n=9[19%]). R-OMB patients were generally younger(66±9 vs. P-OMB, 69±11-years;p=.09) and had lower incidence of smoking exposure(29% vs. P-OMB, 48%;p=.07); however, there were no other differences in demographics or comorbidities. R-OMB was associated with less intraoperative transfusion(0.6 vs. P-OMB, 1.4 units;p=.01) but there were no differences in conduit choice or bypass configuration. The overall 30-day mortality and complication rates were 7%(n=10/145) and 53%(n=77/145), respectively, with no difference between groups. Notably, R-OMB had decreased cardiac(6% vs. P-OMB, 21%;p<.01) and bleeding complication rates(2% vs. P-OMB, 15%;p=.01). The freedom from re-intervention(1- and 5-year:R-OMB-95±4%, 83±9% vs. P-OMB-97±2%, 93±5%, respectively; log-rank p=.21) and survival(1- and 5-year:R-OMB-82±6%, 68±9% vs. P-OMB-84±4%, 66±7%;p=.91) were similar. Independent predictors of all-cause mortality included new postoperative hemodialysis requirement(HR 7.4, 95%CI 3.1-17.3;p<.001), pulmonary(HR 2.7, 95% CI 1.4-5.3;p=.004) and cardiac(HR 2.4, 95% CI 1.1-5.1;p=.04) complications, as well as female sex(HR 2.1, 95%CI 1.03-4.8;p=.04). Notably, R-OMB was not a predictor of death. CONCLUSIONS: The perioperative and longer-term outcomes for a remedial OMB after a failed intraluminal stent or previous open bypass appear to be comparable to a P-OMB. These findings support the recently updated clinical practice guideline recommendations for an endovascular-first approach to treating recurrent CMI due to the significant perioperative complication risk of OMB. However, among the subset of patients deemed ineligible for endoluminal reconstruction after failed mesenteric revascularization, R-OMB results appear to be acceptable and highlights the utility of this strategy in selected patients.
