MESENTERIC VENOUS THROMBOSES - RISK-FACTORS, TREATMENT AND OUTCOME - CASE-STUDY OF 18 PATIENTS

Eighteen patients with an acute thrombosis of the splanchnic veins were reviewed. Most of apparently idiopathic cases of splanchnic vein thrombosis are related to an increased coagulation related to a congenital or acquired defect of haemostasis. The aim of this study was to assess the effects of a new and effective treatment. Nine male and 9 female patients (range of age : 19 to 81 years) experienced a mesenteric venous thrombosis. There were 14 mesenteric vein thromboses with infarction, two transient mesenteric venous ischaemias without bowel infarction and two acute thromboses of the splanchinc veins without bowel ischaemia. A coagulopathy was detected in seven patients : oral contraception, protein C (PC) or antithrombin III (AT III) congenital deficiencies, acquired deficiency of AT III, PC and protein S (PS), polycythaemia in-the post-partum period and primary myeloproliferative disorder. No coagulopathy was associated with thrombosis in eight cases : mesenteric haematoma, splenomegaly, cirrhosis, appendicectomy, cholescytectomy, chronic heart failure, treatment with beta-adrenergic receptor antagonist and digitalis, stenosis of the portal anastomosis after liver transplantation. Twelve patients required surgery eight intestinal bowel resections with immediate anastomosis, four resections without immediate anatomosis. Only one patient underwent a second look for a repeat bowel resection. No death occurred in the early postoperative period and 17 out of 18 patients were alive after 12 years. An oral anticoagulant therapy was undertaken from two months to seven years. However, three patients suffered a recurrent thrombosis. Two of thein required a long-term anticoagulation. Six patients experienced a portal hypertension and oral anticoagulants were discontinued in three of them because of bleeding oesophageal varices. Six patients were treated only by unfractionated heparin (UFH) or low molecular weight heparin (LMWH) followed by oral anticoagulants. After laparotomy, two were only treated with UFH without any bowel resection, as mesenteric venous ischaemia was too extensive. These observations suggest that the choice between an appropriate medical or surgical, treatment is important and must be discussed. Since 1989, the therapeutic choice has been modified by ultrasonography and contrast enhanced computed tomographic scan which confirmes diagnosis, allows to follow up and check the effects of anticoagulation and to choose the time for surgery. When the diagnosis is established and the patient's risk is low, the anticoagulant therapy is decided. UFH is administered by continuous infusion at the average dose of 500 IU . kg-1 . d-1 to obtain an antifactor Xa activity between 0.3 and 0.6 antiXa IU mL-1. When the diagnosis is uncertain and the patient's risk is high, a laparotomy is required. During surgery, UFH must be delivered at a low dose of 100-150 IU . kg-1 . d-1 and progressively increased to obtain the same antifactor Xa activity in two three days. Congenital or acquired AT III or PC deficiencies should be treated by appropriate concentrates. Duration of treatment with oral anticoagulants is not determined and has to be discussed. A 6-month therapy with an INR of 2.0 to 3.0 seems to be reasonable when no coagulopathy is associated with splanchnic venous thrombosis. A long term anticoagulation must be discussed when a coagulopathy is associated with a splanchnic venous thrombosis.