Evaluation of Covered Stents Versus Bare Metal Stents for Endovascular Treatment of Chronic Ischemia Mesenteric Disease.

Chronic Mesenteric Ischemia (CMI) is defined by one or more arterial digestive lesions, responsible for severe mesenteric symptoms. The clinical presentation of CMI is characterized by postprandial abdominal pain and weight loss, leading to severe malnutrition. It is a frequent pathology which affects preferentially the elderly patients of female sex (70%) with cardio-vascular comorbidities. Risk factors include smoking, hypertension, and dyslipidemia.

Despite medical and diagnostic advances, the morbidity and mortality of CMI remain very high (>70%). Optimal management of CMI is based on early diagnosis. Symptomatic patients with CMI should be treated without much delay to relief symptoms (present in 43% patients) and prevent acute mesenteric ischemia.

The three visceral arteries affected by atherosclerotic disease are coeliac trunc, inferior mesenteric artery and Superior Mesenteric Artery (SMA). The SMA is treated the most frequently, because it is the main relevant artery associated with CMI.

Endovascular treatment (angioplasty and stenting) is considered as the first-line treatment for CMI when feasible. It is indicated especially in the case of high grade stenosis or occlusion of the Superior Mesenteric Artery. Two types of stents can be used for this procedure: bare metal stents (BMS) or covered stents (CS).

Even if BMS are standard care there is no consensus on the type of stent to use.

There are very few reported series with large numbers of patients comparing BMS and CS in this indication. However, to our knowledge, no results from a randomized study addressing this issue have ever been published. These are only retrospective with a low level of evidence (IIb). The largest series compared 147 patients with primary intervention for CMI treatment using BMS versus 42 using CS. Treatment with CS showed better results in terms of symptom recurrence (10% vs 32%, p <0.002), restenosis (12% vs 42%, p <0.0002) and re-interventions (10% vs 42%), after at least 1 year of follow-up. Indeed, endovascular treatment using BMS was associated with high incidence of symptoms recurrence despite the satisfying patency rates in both occluded and stenotic vessels.

There are no international guidelines to recommend the use of one or another sort of stent.

The necessity of a randomised study addressing the issue of bare metal versus covered stents deployment seems to be important.

The investigators propose to demonstrate that covered stents presents a better efficacy than bare metal stents, with a multicenter randomized study involving 24 vascular surgical departments of French University Hospitals.