Long-Term Outcomes of Mesenteric Stenting and Analysis of In-Stent Restenosis Duplex Velocity Criteria

Natural history of superior mesenteric artery in-stent restenosis

OBJECTIVE

Superior mesenteric artery (SMA) stenting is the preferred approach for patients with symptomatic SMA-associated chronic mesenteric ischemia (CMI). The durability of this modality is impacted by in-stent restenosis (ISR). Duplex ultrasound (DUS) and computed tomographic angiography (CTA)-measured ISR may be weakly correlated and not uniformly associated with recurrence of presenting symptoms. This study aims to analyze the association between the degree of ISR for patients with CMI and to develop a predictive model for symptom recurrence.

METHODS

Single center, retrospective study included all patients with CMI with SMA stents from the period of 2003 to 2020. Follow-up period analysis included patients' symptoms recurrence, DUS, CTA, and angiography. A receiver operating characteristic (ROC) analysis was used to evaluate whether peak systolic velocity (PSV) was predictive of symptom recurrence. A subgroup analysis of patients (asymptomatic and symptomatic) with SMA ISR was identified; restenosis defined by DUS with peak systolic velocity (PSV) ≥350.

RESULTS

The study included 186 patients with the ROC analysis obtained from 503 postoperative visits. PSV was not a predictor of symptoms return with area under the curve (AUC) = 0.49 (95% confidence interval [CI], 0.40-0.57). Agreement analysis between imaging modalities showed higher agreement between CTA and angiogram (AUC, 0.769; 95% CI, 0.688-0.849) vs CTA and DUS (AUC, 0.650; 95% CI, 0.589-0.711). The subgroup analysis of patients with ISR included 99 patients (asymptomatic n = 67; symptomatic n = 32). There was no statistical difference between median time (months) to ISR between both groups: 4.5 (asymptomatic group) and 7.6 (symptomatic group). The use of preoperative antiplatelet (86% vs 65%; P = .015) and P2Y12 receptor blockers (36% vs 13%; P = .016) was more prevalent in the asymptomatic group. There was no difference between the type or number of stents placed, stent diameter, or concomitant celiac artery intervention between both groups.

CONCLUSIONS

The natural history of SMA and multimodality defined ISR in CMI has not previously been described. Elevated PSV was a poor predictor of symptoms recurrence. Both asymptomatic and symptomatic patients with ISR did not differ in type of stent placed, time to ISR, or involvement of celiac artery. Antiplatelet use pre- and postoperatively appears protective against symptoms recurrence. Our findings underscore the need for long-term surveillance integrating clinical evaluation and multimodality imaging when indicated.

Mesenteric and renal arterial duplex ultrasound: A review

Duplex ultrasound examinations of the mesenteric and renal circulations are commonly used to detect disease as well as to follow up patients after open surgery or endovascular intervention. The aims of this review were to present essential elements of these duplex ultrasound examinations as well as conduct a literature review of diagnostic criteria. Documentation of appropriate images and data will aid in an accurate interpretation. Spectral Doppler waveforms from various segments of these arterial systems can contribute both direct and indirect evidence of the presence of disease. Various studies have validated the duplex ultrasound diagnostic criteria which more recently have expanded to include specific criteria for stented vessels. This review presents a summary of the fundamental exam components and diagnostic criteria utilized for mesenteric and renal duplex ultrasound.

2D-perfusion angiography for intra-procedural endovascular treatment response assessment in chronic mesenteric ischemia: a feasibility study

BACKGROUND

Endovascular revascularization has become the first-line treatment of chronic mesenteric ischemia (CMI). The qualitative visual analysis of digital subtraction angiography (DSA) is dependent on observer experience and prone to interpretation errors. We evaluate the feasibility of 2D-Perfusion Angiography (2D-PA) for objective, quantitative treatment response assessment in CMI.

METHODS

49 revascularizations in 39 patients with imaging based evidence of mesenteric vascular occlusive disease and clinical signs of CMI were included in this retrospective study. To assess perfusion changes by 2D-PA, DSA-series were post-processed using a dedicated, commercially available software. Regions of interest (ROI) were placed in the pre- and post-stenotic artery segment. In aorto-ostial disease, the inflow ROI was positioned at the mesenteric artery orifice. The ratios outflow to inflow ROI for peak density (PD), time to peak and area-under-the-curve (AUC) were computed and compared pre- and post-interventionally. We graded motion artifacts by means of a four-point scale. Feasibility of 2D-PA and changes of flow parameters were evaluated.

RESULTS

Motion artifacts due to a mobile vessel location beneath the diaphragm or within the mesenteric root, branch vessel superimposition and inadequate contrast enhancement at the inflow ROI during manually conducted DSA-series via selective catheters owing to steep vessel angulation, necessitated exclusion of 26 measurements from quantitative flow evaluation. The feasibility rate was 47%. In 23 technically feasible assessments, PDoutflow/PDinflow increased by 65% (p < 0.001) and AUCoutflow/AUCinflow increased by 85% (p < 0.001). The time to peak density values in the outflow ROI accelerated only minimally without reaching statistical significance. Age, BMI, target vessel (celiac trunk, SMA or IMA), stenosis location (ostial or truncal), calcification severity, plaque composition or the presence of a complex stenosis did not reach statistical significance in their distribution among the feasible and non-feasible group (p > 0.05).

CONCLUSIONS

Compared to other vascular territories and indications, the feasibility of 2D-PA in mesenteric revascularization for CMI was limited. Unfavorable anatomic conditions contributed to a high rate of inconclusive 2D-PA results.

Contemporary management of acute and chronic mesenteric ischemia: 10-year experience from a multihospital healthcare system

OBJECTIVE

Endovascular and hybrid methods are being increasingly used to treat mesenteric ischemia. However, long-term outcomes and risk of symptom recurrence remain unknown. The objective of this study was to define predictors of post-operative morbidity, mortality, and patency loss in acute (AMI) or chronic mesenteric ischemia (CMI).

METHODS

Inpatient and follow-up records for all patients who underwent revascularization for AMI and CMI from 2010 to 2020 at a multicenter hospital system were reviewed. Patency and mortality were evaluated with Cox regression, visualized with Kaplan-Meier curves, and compared using log rank testing. Patency was further evaluated with Fine-Gray regression utilizing death as a competing risk. Post-operative major adverse events (MAE) and 30-day mortality were evaluated with logistic regression.

RESULTS

407 patients were included; 148 AMI and 259 CMI. In AMI, 30-day mortality was 31%. Open surgery was associated with lower rates of bowel resection (OR 0.23, 95% CI 0.13, 0.61). Etiology of AMI also did not change outcomes (OR 1.30, 95% CI 0.77, 2.19). Adjusted analyses indicates that a history of diabetes (OR 2.77, 95% CI 1.37, 5.61) and sepsis on presentation (OR 2.32, 95% CI 1.18, 4.58) were independently associated with increased risk of 30-day MAE. In CMI, open surgery and CKD were associated with higher MAE (OR 3.03, 95% CI 1.14, 8.05; OR 2.37, 95% CI 1.31, 4.31) while CKD (OR 3.02, 95% CI 1.10, 8.37) and inpatient status prior to revascularization (OR 2.78, 95% CI 1.01, 7.61) were associated with increased 30-day mortality. In CMI, patients in the endovascular cohort had higher rates of symptom recurrence (29% vs. 13%) with faster onset (endovascular 64 days vs. bypass 338 days).

CONCLUSIONS

AMI remains a morbid disease despite evolving revascularization techniques. An open approach should remain the gold standard as it reduces likelihood of bowel resection. In CMI, endovascular interventions have improved post-operative morbidity but result in early symptom recurrence and re-interventions. An endovascular-first approach should be standard in CMI with close surveillance.