Covered stents versus Bare-metal stents in chronic atherosclerotic Gastrointestinal Ischemia (CoBaGI): study protocol for a randomized controlled trial

Covered versus bare-metal stenting of the mesenteric arteries in patients with chronic mesenteric ischaemia (CoBaGI): a multicentre, patient-blinded and investigator-blinded, randomised controlled trial

BACKGROUND

Mesenteric artery stenting with a bare-metal stent is the current treatment for atherosclerotic chronic mesenteric ischaemia. Long-term patency of bare-metal stents is unsatisfactory due to in-stent intimal hyperplasia. Use of covered stents might improve long-term patency. We aimed to compare the patency of covered stents and bare-metal stents in patients with chronic mesenteric ischaemia.

METHODS

We conducted a multicentre, patient-blinded and investigator-blinded, randomised controlled trial including patients with chronic mesenteric ischaemia undergoing mesenteric artery stenting. Six centres in the Netherlands participated in this study, including two national chronic mesenteric ischaemia expert centres. Patients aged 18 years or older were eligible for inclusion when an endovascular mesenteric artery revascularisation was scheduled and a consensus diagnosis of chronic mesenteric ischaemia was made by a multidisciplinary team of gastroenterologists, interventional radiologists, and vascular surgeons. Exclusion criteria were stenosis length of 25 mm or greater, stenosis caused by median arcuate ligament syndrome or vasculitis, contraindication for CT angiography, or previous target vessel revascularisation. Digital 1:1 block randomisation with block sizes of four or six and stratification by inclusion centre was used to allocate patients to undergo stenting with bare-metal stents or covered stents at the start of the procedure. Patients, physicians performing follow-up, investigators, and radiologists were masked to treatment allocation. Interventionalists performing the procedure were not masked. The primary study outcome was the primary patency of covered stents and bare-metal stents at 24 months of follow-up, evaluated in the modified intention-to-treat population, in which stents with missing data for the outcome were excluded. Loss of primary patency was defined as the performance of a re-intervention to preserve patency, or 75% or greater luminal surface area reduction of the target vessel. CT angiography was performed at 6 months, 12 months, and 24 months post intervention to assess patency. The study is registered with ClinicalTrials.gov (NCT02428582) and is complete.

FINDINGS

Between April 6, 2015, and March 11, 2019, 158 eligible patients underwent mesenteric artery stenting procedures, of whom 94 patients (with 128 stents) provided consent and were included in the study. 47 patients (62 stents) were assigned to the covered stents group (median age 69·0 years [IQR 63·0-76·5], 28 [60%] female) and 47 patients (66 stents) were assigned to the bare-metal stents group (median age 70·0 years [63·5-76·5], 33 [70%] female). At 24 months, the primary patency of covered stents (42 [81%] of 52 stents) was superior to that of bare-metal stents (26 [49%] of 53; odds ratio [OR] 4·4 [95% CI 1·8-10·5]; p<0·0001). A procedure-related adverse event occurred in 17 (36%) of 47 patients in the covered stents group versus nine (19%) of 47 in the bare-metal stent group (OR 2·4 [95% CI 0·9-6·3]; p=0·065). Most adverse events were related to the access site, including haematoma (five [11%] in the covered stents group vs six [13%] in the bare-metal stents group), pseudoaneurysm (five [11%] vs two [4%]), radial artery thrombosis (one [2%] vs none), and intravascular closure device (none vs one [2%]). Six (13%) patients in the covered stent group versus one (2%) in the bare-metal stent group had procedure-related adverse events not related to the access site, including stent luxation (three [6%] vs none), major bleeding (two (4%) vs none), mesenteric artery perforation (one [2%] vs one [2%]), mesenteric artery dissection (one [2%] vs one [2%]), and death (one [2%] vs none).

INTERPRETATION

The findings of this trial support the use of covered stents for mesenteric artery stenting in patients with chronic mesenteric ischaemia.

FUNDING

Atrium Maquet Getinge Group.

Advancements in Treatment Strategies for Chronic Mesenteric Ischemia: A Comprehensive Review

Chronic mesenteric ischemia (CMI) arises from the inability to achieve adequate intestinal blood flow after meals, leading to an imbalance between oxygen and metabolite supply and demand. The true incidence of CMI remains uncertain. However, the occurrence of mesenteric artery occlusive disease (MAOD) is relatively common among the elderly population. Delays in diagnosing CMI can often be attributed to several factors, including the variability in patient symptoms and the range of potential causes for chronic abdominal pain with weight loss. Mikkelson pioneered the introduction of a surgical treatment for occlusive lesions of the superior mesenteric artery (SMA) in 1957. The inaugural performance of endovascular revascularization (ER) for visceral vessels took place in 1980. The literature has documented two types of endovascular revascularization (ER) methods: percutaneous transluminal angioplasty (PTA) and primary stenting (PMAS). Despite the limited quality of available evidence, the consensus among experts is strongly in favor of PMAS over PTA alone for the treatment of atherosclerotic mesenteric artery stenosis. There are several key areas of focus for chronic mesenteric ischemia (CMI) treatment. Randomized controlled trials comparing different stent types, such as covered stents versus bare metal stents, are needed to evaluate efficacy, patency rates, and long-term outcomes in CMI patients.

A Systematic Review of Endovascular Repair Outcomes in Atherosclerotic Chronic Mesenteric Ischaemia

OBJECTIVE

Chronic mesenteric ischaemia (CMI) treatment focuses on symptom relief and prevention of disease progression. Endovascular repair represents the main treatment modality, while data on the associated antiplatelet regimen are scarce. The aim of this meta-analysis was to assess the early and midterm outcomes of endovascular repair in patients with CMI.

DATA SOURCES

Randomised controlled trials and observational studies (1990 - 2022) reporting on early and midterm endovascular repair outcomes in patients with atherosclerotic CMI.

REVIEW METHODS

The PRISMA guidelines and PICO model were followed. The protocol was registered to PROSPERO (CRD42023401685). Medline, Embase (via Ovid), and Cochrane databases were searched (end date 21 February 2023). The Newcastle-Ottawa Scale was used for risk of bias assessment, and GRADE for evidence quality assessment. Primary outcomes were technical success, 30 day mortality, and symptom relief, assessed using prevalence meta-analysis. The role of dual antiplatelet therapy (DAPT) was investigated using meta-regression analysis.

RESULTS

Sixteen retrospective studies (1 224 patients; mean age 69.8 ± 10.6 years; 60.3% female) reporting on 1 368 target vessels (57.8% superior mesenteric arteries) were included. Technical success was 95.0% (95% CI 93 - 97%, p = .28, I2 19%, low certainty), the 30 day mortality rate was 2.0% (95% CI 2 - 4%, p = .93, I2 36%, low certainty), and immediate symptom relief was 87.0% (95% CI 80 - 92%, p < .010, I2 85%, very low certainty). At mean follow up of 28 months, the mortality rate was 15.0% (95% CI 9 - 25%, p = .010, I2 86%, very low certainty), symptom recurrence 25.0% (95% CI 21 - 31%, p < .010, I2 68%, very low certainty) and re-intervention rate 26.0% (95% CI 17 - 37%, p < .010, I2 92%, very low certainty). Single antiplatelet therapy (SAPT) and DAPT performed similarly in the investigated outcomes.

CONCLUSION

Endovascular repair for CMI appears to be safe as first line treatment, with a low peri-operative mortality rate and acceptable immediate symptom relief. During midterm follow up, symptom recurrence and need for re-intervention are not uncommon. SAPT appears to be equal to DAPT in post-operative outcomes.

Cost-Effectiveness Analysis of Open Versus Endovascular Revascularization for Chronic Mesenteric Ischemia

BACKGROUND

Recent studies have shown a trend supporting endovascular revascularization (ER) in the treatment of chronic mesenteric ischemia (CMI). However, few studies have compared the cost effectiveness of ER and open revascularization (OR) for this indication. The purpose of this study is to conduct a cost-effectiveness analysis comparing open versus ER for CMI.

METHODS

We built a Markov model with Monte Carlo microsimulation using transition probabilities and utilities from existing literature for CMI patients undergoing OR versus ER. Costs were derived from the hospital perspective using the 2020 Medicare Physician Fee Schedule. The model randomized 20,000 patients to either OR or ER and allowed for 1 subsequent reintervention with 3 other intervening health states: alive, alive with complications, and dead. Quality-adjusted life years (QALYs), costs, and incremental cost-effectiveness ratio (ICER) were analyzed over a 5-year period. One-way sensitivity and probabilistic sensitivity analyses were conducted to study the impact of parameter variability on cost effectiveness.

RESULTS

OR cost $4,532 for 1.03 QALYs while ER cost $5,092 for 1.21 QALYs, leading to an ICER of $3,037 per QALY gained in the ER arm. This ICER was less than our willingness to pay threshold of $100,000. Sensitivity analysis demonstrated that our model was most sensitive to costs, mortality, and patency rates after OR and ER. Probabilistic sensitivity analysis demonstrated ER would be considered cost effective 99% of iterations.

CONCLUSIONS

This study found that while 5-year costs for ER were greater than OR, ER afforded greater QALYs than OR. Although ER is associated with lower long-term patency and higher rates of reintervention, it appears to be more cost effective than OR for the treatment of CMI.

Novel Endovascular Interventional Surgical Robotic System Based on Biomimetic Manipulation

Endovascular therapy has emerged as a crucial therapeutic method for treating vascular diseases. Endovascular surgical robots have been used to enhance endovascular therapy. However, to date, there are no universal endovascular surgical robots that support molds of different types of devices for treating vascular diseases. We developed a novel endovascular surgical robotic system that can independently navigate the intravascular region, advance and retract devices, and deploy stents. This robot has four features: (1) The bionic design of the robot can fully simulate the entire grasping process; (2) the V-shaped relay gripper waived the need to redesign special guidewires and catheters for continuous rotation; (3) the handles designed based on the feedback mechanism can simulate push resistance and reduce iatrogenic damage; and (4) the detachable design of the grippers can reduce cross-infection risk and medical costs. We verified its performance by demonstrating six different types of endovascular surgeries. Early evaluation of the novel endovascular robotic system demonstrated its practicability and safety in endovascular surgeries.

Chronic mesenteric ischemia: causes, methods of diagnosis and treatment

Chronic mesenteric ischemia (CMI) is an urgent public health problem. The long asymptomatic course of the disease, sudden onset and an unfavorable prognosis in the absence of treatment make it necessary to pay closer attention to this pathology. There are currently two competitive treatments for CMI: surgical and endovascular revascularization. Despite numerous studies comparing these methods, the question of which one is more effective and reliable remains open. The review includes current data from clinical trials and meta-analyses demonstrating the advantages and disadvantages of both methods.

Factors predicting long-term outcomes of percutaneous angioplasty and stenting of the superior mesenteric artery for chronic mesenteric ischemia

Background: To analyse the long-term outcomes of percutaneous angioplasty and stenting of the superior mesenteric artery (SMA) in the treatment of chronic mesenteric ischemia (CMI), and to assess predictive factors for a better clinical outcome. Patients and methods: Retrospective analysis of 76 consecutive patients, treated percutaneously for CMI between January 1999 and January 2018 and followed up until the end of 2018. Patients' pre-, peri- and post-interventional clinical and radiological data were gathered from the institutional electronic medical records. The Kaplan Meier method with log rank test or the Cox model were used to analyse overall survival; the cumulative incidence function with Pepe and Mori test or the Fine and Grey model were used to analyse relapse-free survival, considering death as a competing event. Results: Seventy-six consecutive patients with a mean age of 72 years were included in the study. Catheter-angiography revealed an ostial or non-ostial >90% stenosis in n=23 (29.7%) and n=53 (69.7%) of included patients, respectively. Immediate clinical success was achieved in n=68 (89.5%), and procedural complications were observed in n=13 (17.1%) patients. Long-term follow-up revealed relapse of symptoms in n=21 (28.8%) patients, and overall survival estimates are 81.8%, 57.0% and 28.2% after two, five and ten years of follow-up, respectively. A trend towards longer relapse-free survival was found in the circumferential stenosis group (78.2% at five years) compared with the non-circumferential stenosis group (55.5%) (P=0.063). Conclusions: Angioplasty and stenting of the SMA for CMI is relatively safe and effective despite a substantial number of patients experiencing clinical relapse over time. Patients with focal, circumferential stenosis might have longer relapse-free survival than patients with non-circumferential stenosis.

Midterm results after covered stenting of the superior mesenteric artery

OBJECTIVE

Despite the continuing controversy of covered stents (CS) vs bare metal stents, the use of CS in mesenteric occlusive disease (MOD) has been recommended by expert centers. The aim of this study was to report midterm results with CS of the superior mesenteric artery.

METHODS

Between January 2014 and October 2019, patients with MOD with a severe atheromatous stenosis or occlusion of the superior mesenteric artery treated by mesenteric CS were included. Clinical presentation included both acute mesenteric ischemia (AMI), chronic mesenteric ischemia, and asymptomatic patients planned for major surgery. Demographics, procedure details, and follow-up data were prospectively collected and retrospectively reviewed. Study end points included primary patency, primary assisted patency, and secondary patency.

RESULTS

During the study period, 86 patients (mean age, 70 ± 9 years; 57% males) were included. Clinical presentation was AMI (n = 42 [49%]), chronic mesenteric ischemia (n = 31 [36%]), and asymptomatic (n = 13 [15%]). The technical success rate was 97%. A total of 96 stents were implanted, including 86 proximal CS (Advanta V12, n = 73; Lifestream, n = 13). The mean length and mean diameter of the CS were 31.5 ± 6.3 mm and 6.9 ± 0.5 mm, respectively. Additional distal bare metal stents were used in 10 patients (12%) to overcome a kinking (n = 9) or a dissection (n = 1) downstream of the CS. All postoperative deaths occurred in patients with AMI (n = 11, 13%). During a median follow-up of 15.6 months (95% confidence interval [CI], 15.6 ± 3.6 months), 12 patients (14%) underwent reinterventions for either stent misplacement (n = 3), stent recoil (n = 3), stent thrombosis (n = 2), de novo stenosis at the distal edge of the CS (n = 2), or gastric ischemia (n = 1). At 1 year, overall the primary patency, primary assisted patency, and secondary patency rates were 83% (95% CI, 83% ± 9%), 99% (95% CI, 99% ± 3%), and 99% (95% CI, 99% ± 3%), respectively. At 2 years, the overall primary patency, primary assisted patency, and secondary patency rates were 76% (95% CI, 76% ± 13%), 95% (95% CI, 95% ± 8%) and 95% (95% CI, 95% ± 8%), respectively.

CONCLUSIONS

Mesenteric CS provide very satisfactory midterm results in patients with MOD, with an excellent primary assisted patency rate at 2 years, at the price of a significant reintervention rate.

Chronic mesenteric ischemia: Clinical practice guidelines from the Society for Vascular Surgery

BACKGROUND

Chronic mesenteric ischemia (CMI) results from the inability to achieve adequate postprandial intestinal blood flow, usually from atherosclerotic occlusive disease at the origins of the mesenteric vessels. Patients typically present with postprandial pain, food fear, and weight loss, although they can present with acute mesenteric ischemia and bowel infarction. The diagnosis requires a combination of the appropriate clinical symptoms and significant mesenteric artery occlusive disease, although it is often delayed given the spectrum of gastrointestinal disorders associated with abdominal pain and weight loss. The treatment goals include relieving the presenting symptoms, preventing progression to acute mesenteric ischemia, and improving overall quality of life. These practice guidelines were developed to provide the best possible evidence for the diagnosis and treatment of patients with CMI from atherosclerosis.

METHODS

The Society for Vascular Surgery established a committee composed of vascular surgeons and individuals experienced with evidence-based reviews. The committee focused on six specific areas, including the diagnostic evaluation, indications for treatment, choice of treatment, perioperative evaluation, endovascular/open revascularization, and surveillance/remediation. A formal systematic review was performed by the evidence team to identify the optimal technique for revascularization. Specific practice recommendations were developed using the Grading of Recommendations Assessment, Development, and Evaluation system based on review of literature, the strength of the data, and consensus.

RESULTS

Patients with symptoms consistent with CMI should undergo an expedited workup, including a computed tomography arteriogram, to exclude other potential causes. The diagnosis is supported by significant arterial occlusive disease in the mesenteric vessels, particularly the superior mesenteric artery. Treatment requires revascularization with the primary target being the superior mesenteric artery. Endovascular revascularization with a balloon-expandable covered intraluminal stent is the recommended initial treatment with open repair reserved for select younger patients and those who are not endovascular candidates. Long-term follow-up and surveillance are recommended after revascularization and for asymptomatic patients with severe mesenteric occlusive disease. Patient with recurrent symptoms after revascularization owing to recurrent stenoses should be treated with an endovascular-first approach, similar to the de novo lesion.

CONCLUSIONS

These practice guidelines were developed based on the best available evidence. They should help to optimize the care of patients with CMI. Multiple areas for future research were identified.

European guidelines on chronic mesenteric ischaemia - joint United European Gastroenterology, European Association for Gastroenterology, Endoscopy and Nutrition, European Society of Gastrointestinal and Abdominal Radiology, Netherlands Association of Hepatogastroenterologists, Hellenic Society of Gastroenterology, Cardiovascular and Interventional Radiological Society of Europe, and Dutch Mesenteric Ischemia Study group clinical guidelines on the diagnosis and treatment of patients with chronic mesenteric ischaemia

Chronic mesenteric ischaemia is a severe and incapacitating disease, causing complaints of post-prandial pain, fear of eating and weight loss. Even though chronic mesenteric ischaemia may progress to acute mesenteric ischaemia, chronic mesenteric ischaemia remains an underappreciated and undertreated disease entity. Probable explanations are the lack of knowledge and awareness among physicians and the lack of a gold standard diagnostic test. The underappreciation of this disease results in diagnostic delays, underdiagnosis and undertreating of patients with chronic mesenteric ischaemia, potentially resulting in fatal acute mesenteric ischaemia. This guideline provides a comprehensive overview and repository of the current evidence and multidisciplinary expert agreement on pertinent issues regarding diagnosis and treatment, and provides guidance in the multidisciplinary field of chronic mesenteric ischaemia.

Endovascular Pressure Measurements to Assess the Functional Severity of Mesenteric Arterial Stenoses

PURPOSE

To assess the ability of pressure measurements to discriminate clinically significant celiac artery (CA) or superior mesenteric artery (SMA) stenosis in patients with suspected chronic mesenteric ischemia (CMI).

MATERIALS AND METHODS

Single-center, retrospective cohort study of 41 intra-arterial pressure measurements during mesenteric angiography with intended revascularization, performed in 37 patients (mean age 67.7 ± 10.8 years, 62% female) between April 2015 and May 2017. Simultaneous prestenotic and poststenotic pressure measurements had been obtained before and after intra-arterial administration of nitroglycerin. Revascularization was performed in 38 of 41 procedures. Definitive diagnosis of CMI was defined as patient-reported symptom relief or improvement after successful revascularization.

RESULTS

Pressure gradients obtained after vasodilator administration were significantly higher in CAs and SMAs with ≥50% stenosis. Pressure ratios (pressure distal [Pd]/pressure aorta [Pa]) obtained after vasodilator administration were significantly higher in CAs with ≥50% stenosis. Subgroup analysis of 22 patients with a ≥50% stenosis of either CA or SMA showed significantly higher pressure gradients and Pd/Pa ratios after vasodilator administration in CMI patients (median pressure gradient: CMI [interquartile ratio] 36 [21-40] mm Hg versus no-CMI 20 [9-21] mm Hg, P = 0.041; Pd/Pa: CMI 0.703 [0.598-0.769] versus no-CMI 0.827 [0.818-0.906], P = .009). A ≤0.8 Pd/Pa cutoff value after administration of a vasodilator best identified a clinically relevant stenosis, with 86% sensitivity and 83% specificity. Complications related to the pressure measurements were not observed.

CONCLUSIONS

Intra-arterial pressure measurements are feasible and safe. Low Pd/Pa ratios were associated with clinically relevant CA or SMA stenosis.