Failure Modes of Endovascular Therapy for Spontaneous Isolated Superior Mesenteric Artery Dissection.

Abstract

Background: Mechanisms of failure after endovascular stenting for symptomatic spontaneous isolated superior mesenteric artery dissection (SISMAD) remain poorly characterized. We analyzed device- and procedure-related failure modes in a 17-year single-center cohort.

Methods: We reviewed 117 consecutive patients with SISMAD (2008-2025). Patients stented for persistent or escalating pain despite conservative management formed the cohort; catheter-infusion and open-surgery patients were analyzed separately. Lesions were classified by Yun morphology. Failure modes were classified a priori as type I (intraprocedural technical failure), type II (thrombotic events occurring after the procedure), and type III (in-stent restenosis or intimal hyperplasia at ≥6 months). Patency and reinterventions were recorded.

Results: Thirty-two patients underwent endovascular therapy (28 stenting, 4 catheter-directed infusion). In the stent cohort, uncomplicated technical success was 82.1% (23/28). Type I failures occurred in 17.9% (5/28), dominated by false-lumen deployment (10.7%) clustered in Yun III occlusions (50.0% vs. 9.1%; P = 0.050). Type II events (3 weeks; 24 months) were rescued by reintervention. Type III events developed in 22.7% (5/22), confined to multi-stent constructs (45.5% vs. 0%; P = 0.035). Primary patency was 81.8% (18/22) at a median 19-month imaging follow-up; secondary patency was 100% after 3 reinterventions. Greater baseline true-lumen stenosis and Yun III morphology predicted composite events. No patient died; the only bowel resection preceded secondary stenting.

Conclusion: Endovascular therapy for SISMAD fails in characteristic, morphology-dependent patterns. The proposed three-type classification is exploratory and requires validation in larger cohorts.