Outcomes of Open Bypass and SMA Endarterectomy for Patients with Chronic Mesenteric Ischemia Resulting from Long-segment SMA Occlusive Disease.

Abstract

Background: Chronic mesenteric ischemia(CMI) from atherosclerotic occlusive disease commonly involves the origin of the superior mesenteric artery(SMA) and is often treated with covered endoluminal stents. Notably, diffuse SMA arterial occlusive disease(>4 cm) extending beyond the ostium precludes standard endovascular treatment and may require open mesenteric bypass with endarterectomy(OMB-EA); however, the outcomes and durability of this approach remain incompletely defined. This study was designed to examine the impact of OMB-EA in CMI patients with diffuse SMA occlusive disease.

Methods: A single-center, retrospective review of patients undergoing OMB for CMI from 2002 to 2024 was completed. Patients receiving OMB-EA were compared to those undergoing OMB alone. The primary endpoint was 30-day mortality. Secondary outcomes included perioperative complications, reintervention, symptom recurrence, primary patency and overall survival. Kaplan-Meier survival analysis and propensity-matched comparisons were used to assess differences between groups.

Results: Among 166 patients undergoing OMB for CMI, 138 (83%) had OMB alone and 28 (17%) underwent OMB-EA. Demographics were similar (median age 71 [IQR 65-76]; 69% female), although OMB-EA patients were more likely to have end-stage kidney disease (7% vs. 0; p=.03), but had lower rates of peripheral arterial disease (11% vs. 50%; p=.001) and congestive heart failure (4% vs. 19%; p=.05). OMB-EA patients more often underwent retrograde bypass (39% vs. 19%; p=.03) and received greater intraoperative transfusion (median[IQR]: 3[0.25,4.75] vs. 1[0,3] units; p=.04). There were no differences in 30-day mortality (4% vs. 3%; p=1.0) or major complications (46% vs. 54%; p=.5). Median follow-up time was 2.0 years and overall survival at 1 and 2-years was similar between groups (OMB: 86±3% and 67±5% vs. OMB-EA: 89±7% and 72±13%; log-rank p=.2). Rates of symptom recurrence (8% vs. 4%; p=.7), reintervention (5% vs. 7%; p=.6), and readmission (10% vs. 11%; p=.7) were also comparable. However, OMB-EA patients had shorter time to reintervention (0.03 vs. 1.2 years; p=.04) and lower 1-year primary patency (93±7% vs. 100%; log-rank p=.007). Similarly, propensity-matched analysis(N=27 pairs) showed no significant differences in mortality or complication outcomes.

Conclusions: OMB with SMA endarterectomy is associated with similar survival and complication rates compared to OMB alone, despite greater procedural complexity. These findings support an aggressive approach to using SMA endarterectomy and OMB for patients with CMI and diffuse SMA occlusive disease.