Portal, mesenteric, and splenic vein thromboses after endovascular embolization for gastrointestinal bleeding caused by a splenic arteriovenous fistula.

We present an unusual case of portal, mesenteric, and splenic vein thromboses after endovascular embolization for gastrointestinal bleeding caused by a splenic arteriovenous fistula. The thromboses were successfully treated with anticoagulation therapy. The patient was a 37-year-old woman who presented with portal hypertension manifested by gastrointestinal bleeding with no evidence of liver disease. Splenic arteriography confirmed the presence of a high-flow arteriovenous fistulous communication from the splenic artery directly into the splenic vein. The arteriovenous fistula was successfully treated with percutaneous transarterial embolization by embolization coils and the patient achieved effective hemostasis. Low-molecular-weight heparin and warfarin were administrated to prevent thrombosis in the portal venous system after the procedure. Although anticoagulants were immediately administered, thromboses of the portal, mesenteric, and splenic veins were diagnosed by contrast-enhanced computed tomography after 10 days. Complete recanalization of the portal venous system confirmed by contrast-enhanced computed tomography was achieved by administering warfarin orally for 3 months.