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

Eighteen patients with an acute thrombosis of the splanchnic veins wer e reviewed. Most of apparently idiopathic cases of splanchnic vein thr ombosis are related to an increased coagulation related to a congenita l or acquired defect of haemostasis. The aim of this study was to asse ss the effects of a new and effective treatment. Nine male and 9 femal e patients (range of age : 19 to 81 years) experienced a mesenteric ve nous thrombosis. There were 14 mesenteric vein thromboses with infarct ion, two transient mesenteric venous ischaemias without bowel infarcti on and two acute thromboses of the splanchinc veins without bowel isch aemia. A coagulopathy was detected in seven patients : oral contracept ion, protein C (PC) or antithrombin III (AT III) congenital deficienci es, acquired deficiency of AT III, PC and protein S (PS), polycythaemi a in-the post-partum period and primary myeloproliferative disorder. N o coagulopathy was associated with thrombosis in eight cases : mesente ric haematoma, splenomegaly, cirrhosis, appendicectomy, cholescytectom y, chronic heart failure, treatment with beta-adrenergic receptor anta gonist and digitalis, stenosis of the portal anastomosis after liver t ransplantation. Twelve patients required surgery eight intestinal bowe l resections with immediate anastomosis, four resections without immed iate 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 anticoagu lant therapy was undertaken from two months to seven years. However, t hree patients suffered a recurrent thrombosis. Two of thein required a long-term anticoagulation. Six patients experienced a portal hyperten sion and oral anticoagulants were discontinued in three of them becaus e of bleeding oesophageal varices. Six patients were treated only by u nfractionated heparin (UFH) or low molecular weight heparin (LMWH) fol lowed by oral anticoagulants. After laparotomy, two were only treated with UFH without any bowel resection, as mesenteric venous ischaemia w as too extensive. These observations suggest that the choice between a n appropriate medical or surgical, treatment is important and must be discussed. Since 1989, the therapeutic choice has been modified by ult rasonography and contrast enhanced computed tomographic scan which con firmes diagnosis, allows to follow up and check the effects of anticoa gulation and to choose the time for surgery. When the diagnosis is est ablished and the patient's risk is low, the anticoagulant therapy is d ecided. 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 pati ent'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 progressive ly increased to obtain the same antifactor Xa activity in two three da ys. Congenital or acquired AT III or PC deficiencies should be treated by appropriate concentrates. Duration of treatment with oral anticoag ulants is not determined and has to be discussed. A 6-month therapy wi th an INR of 2.0 to 3.0 seems to be reasonable when no coagulopathy is associated with splanchnic venous thrombosis. A long term anticoagula tion must be discussed when a coagulopathy is associated with a splanc hnic venous thrombosis.