Management of Acute Mesenteric Venous Thrombosis: A Systematic Review of Contemporary Studies

Abstract

Background and aims: Acute mesenteric venous thrombosis accounts for up to 20% of all patients with acute mesenteric ischemia in high-income countries. Acute mesenteric venous thrombosis is nowadays relatively more often diagnosed with intravenous contrast-enhanced computed tomography in the portal phase than at explorative laparotomy No high-quality comparative studies between anticoagulation alone, endovascular therapy, or surgery exists. The aim of the present systematic review was to offer a contemporary overview on management.

Materials and methods: Eleven relevant published original studies with series of at least ten patients were retrieved from a Pub Med search between 2015 and 2020 using the Medical Subject Heading term "mesenteric venous thrombosis."

Results: When MVT is diagnosed early, immediate anticoagulation with either unfractionated heparin or subcutaneous low-molecular-weight heparin should commence. Surgeons need to be aware of the importance to scrutinize the computed tomography images themselves for assessment of secondary intestinal abnormalities to mesenteric venous thrombosis and the risk of bowel resection and worse prognosis. Progression toward peritonitis is an indication for explorative laparotomy and assessment of bowel viability. Frank transmural small bowel necrosis should be resected and bowel anastomosis may be delayed for several days until second look. Meanwhile, intravenous full-dose unfractionated heparin should be given at the end of the first operation. Postoperative major intra-abdominal or gastrointestinal bleeding occurs rarely, but the heparin effect can instantaneously be reversed by protamine sulfate. Patients who do not improve during conservative therapy with anticoagulation alone but without developing peritonitis may be subjected to endovascular therapy in expert centers. When the patient's intestinal function has recovered, with or without bowel resection, switch from parenteral unfractionated heparin or low-molecular-weight heparin therapy to oral anticoagulation can be performed. There is a trend that direct oral anticoagulants are increasingly used instead of vitamin K antagonists. Up to now, direct oral anticoagulants have been shown to be equally effective with the same rate of bleeding complications. Patients with no strong permanent trigger factor for mesenteric venous thrombosis such as intra-abdominal cancer should undergo blood screening for inherited and acquired thrombophilia.

Conclusion: Early diagnosis with emergency computed tomography with intravenous contrast-enhancement and imaging in the portal phase and anticoagulation therapy is necessary to be able to have a succesful non-operative succesful course.

Keywords: Acute care surgery and trauma; anticoagulation; intestinal ischemia; management; mesenteric venous thrombosis; vascular surgery.

Fig. 1.

A CT with intravenous contrast enhancement in the portal phase showed MVT (two thin arrows). Note the secondary intestinal abnormalities such as dilated small bowel loops (thick arrow), mesenteric edema (dashed line), and ascites (dotted line).

Fig. 2.

Explorative laparotomy in a patient with MVT. At laparotomy, 0.4 m of the most reddish and severely ischemic segment (thin arrow) was resected and anastomosed. Note the distended small bowel loops (thick black arrows) and the edema in the adjacent mesentery (dashed line). Histopathology of the resected bowel did not show transmural infarction but did show infarcted mucosa and venous thrombosis. It is uncertain whether bowel resection really was necessary or if the ischemic bowel would have recovered without bowel resection and anticoagulation therapy alone.

Fig. 3.

A–D) Schematic drawings of various ways of local delivery of thrombolysis for MVT. Usually a special catheter with multiple side holes will be placed directly in the thrombus (A, B, D). An occluding ball wire at the catheter tip end hole (not shown) will allow for even pressure distribution of lytic agent at the side holes. Typically, an intestinal segment of the jejunum and/or ileum will be swollen and ischemic. A) Percutaneous hepatic access. B) Percutaneous transjugular intrahepatic portosystemic shunt including stent graft placement in the shunt. C) Percutaneous transfemoral access and indirect thrombolysis by an endhole catheter placed in the superior mesenteric artery. D) Intra-operatively placed catheter in the superior mesenteric vein at laparotomy. Source: Salim S. On Acute Mesenteric Venous Thrombosis. Lund: Lund University, 2020. Figures reused by permission from Robin Tran.

Fig. 4.

Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) flowchart describing the literature search.

Fig. 5.

Suggested algorithm for management of acute MVT.