NCT06236633

Safety & Efficacy of Ischemic Preconditioning by Embolization of the Inferior Mesenteric Artery in Surgery for Tumors of Lower and Middle Rectum

Evaluation of the Safety and Efficacy of Ischemic Preconditioning by Embolization of the Inferior Mesenteric Artery in Oncologic Surgery for Tumors of the Lower and Middle Rectum. Bicentric Exploratory Pilot Study

• Status: Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 30 (estimated)
• Sponsor: Centre Hospitalier Universitaire de Nīmes · Academic / Other
• Sex: All
• Age: 18 Years – 90 Years
• Healthy volunteers: Not accepted

Summary

The present study will investigate the safety of inferior mesenteric artery embolization prior to rectal surgery, according to IDEAL recommendations (Lancet 2009). It aims to assess the safety of endovascular embolization of the inferior mesenteric artery prior to surgery in patients with rectal tumors, and estimate the potential benefits in terms of time to surgery and the occurrence of post-operative fistulas.The study will also assess the impact of subacute ischemia induced by IMA embolization on colonic vasculature remodeling, colonic ischemic suffering, altered hemostasis and initiation of neo-angiogenesis through blood sampling kinetics.The hypothesis is that ischemic preconditioning by inferior mesenteric artery embolization prior to rectal cancer resection surgery is safe and will result in a decrease in acute relative colon ischemia and a reduction in the rate of fistulas and post-surgical complications. Indeed, we believe that the beneficial effects of the ischemic preconditioning of IMA will be due to better blood perfusion of the colon at 3 weeks, which is apparently linked to remodeling and/or the development of collateral vascularization.

Detailed description

Anastomotic fistulas are the main cause of morbidity and mortality in colorectal surgery. They are responsible for septic complications, leading to increased mortality, local recurrence, repeat surgery and impaired sexual, urinary and digestive function. Fistulas are multifactorial; among the causes, colonic vascularization seems to be a major one. Ligation of the inferior mesenteric artery during rectal surgery has been shown to reduce intraoperative colonic perfusion flow. The left colon is then vascularized only by the colonic border arcade, perfused by the superior mesenteric artery. Ischemic pre-conditioning of the arterial network prior to surgery should ensure better vascularization by developing arterial collaterality and increasing perfusion flow in the colonic border arcade. In view of major advances in interventional radiology, this preconditioning could be achieved by endovascular ligation of the inferior mesenteric artery (IMA), based on the same principle as during surgery: proximal occlusion of the inferior mesenteric artery (IMA), using embolization material (plug or coils), 3 weeks before surgery, to allow the colonic border arcade to develop. We carried out a single-center pilot study (AMIREMBOL 1, NIMAO 2017; Frandon et al. 2022) to assess the feasibility of ischemic preconditioning of the colon for patients with rectal or sigmoid cancer. The study included 10 patients, randomized into two groups: the control group, with preoperative arteriography and standard management and the "embolization" group, with embolization of the IMA three weeks prior to surgery. IMA embolization was successfully performed in all 5 patients in the embolization group, with no major complications. The effect on colonic perfusion, measured by intraoperative Doppler directly on the border arch, with recording of resistance indexes (independent of measurement angle), showed a drop in resistance indexes in the control arm, after ligation of the IMA, which persisted after 5 minutes. In the "Embolization" arm, no drop in this index was reported during surgery, reflecting good development of vascular collaterality and at least relative acute ischemia of the colon after IMA ligation during surgery. Finally, in the "control" group, one anastomotic fistula was reported after surgery and required re-operation. There were no fistulas in the embolization group. The present study (AMIREMBOL 2) will investigate the safety of IMA embolization prior to rectal surgery, according to IDEAL recommendations (Lancet 2009). Its aim is to assess the safety of endovascular embolization of the IMA prior to surgery in patients with rectal tumors, and to estimate the potential benefits in terms of time to surgery and the occurrence of post-operative fistulas. The study will also assess the impact of subacute ischemia induced by IMA embolization on colonic vasculature remodeling, colonic ischemic suffering, altered hemostasis and initiation of neo-angiogenesis through blood sampling kinetics. The hypothesis is that ischemic preconditioning by inferior mesenteric artery (IMA) embolization prior to rectal cancer resection surgery is safe and will result in a decrease in acute relative colon ischemia and a reduction in the rate of fistulas and post-surgical complications. The hypothesis is that the beneficial effects of the ischemic preconditioning of IMA will be due to better blood perfusion of the colon at 3 weeks, which is apparently linked to remodeling and/or the development of collateral vascularization.

Conditions

• Cancer, Rectal

Interventions

Type	Name	Description
PROCEDURE	Ischemic preconditioning	Embolization performed via a common right femoral or radial approach, depending on the patient's conformation. Minor complications such as hematoma at the puncture site are rare in less than 1% of cases, and serious complications are exceptional. Proximal occlusion of the inferior mesenteric artery, before its dividing branches, using material adapted to arterial occlusion according to anatomical findings. Proximal occlusion during embolization is evaluated by intravascular injection into the inferior mesenteric artery, and resumption of vascularization of the distal inferior mesenteric artery is controlled by the border arcade injecting into the superior mesenteric artery. In the event of a high-risk anatomical variant, or absence of a border arcade, no embolization will be performed and the patient will be excluded from the study; this will represent no more than 1-2% of patients (surgical series describing 0.83% of ischemia in connection with absence of a border arcade).
PROCEDURE	Arteriogram	The interventional radiologist performs an arteriogram of the inferior and superior mesenteric arteries (IMA and SMA respectively) to check that the SMA is free of anomalies and that the IMA has a proximal trunk long enough for embolization. The radiologist also checks for the presence of a colonic border arcade. If this is absent, embolization will not be performed: the patient will be excluded from the study.This arteriogram is carried out under local anaesthetic specifically for research purposes, as follows: Common right femoral or radial approach and placement of a small introducer. Selective arteriogram of the inferior and superior mesenteric arteries to check perfusion of the border arcade.Arterial closure system or manual compression. Return to surgery or interventional radiology department. Patient discharged the same day after medical assessment (surgeon or interventional radiologist).Telephone check-up on Day1 (standard management) and Day 7 (added as part of the protocol).

Timeline

• Start date: 2024-08-02
• Primary completion: 2026-08-01
• Completion: 2027-08-01
• First posted: 2024-02-01
• Last updated: 2025-12-04

Locations

3 sites across 1 country: France