Extrahepatic Portal Venous Hypertension in Adults

MR angiography of the portal venous system

MR angiography (MRA) has become an increasingly important and practical clinical tool for the noninvasive assessment of abdominal vessels. Both two-dimensional time-of-flight and phase contrast techniques allow accurate evaluation of the portal venous system. This article reviews these two MRA techniques and discusses their impact on the diagnosis of vascular abnormalities of the portal venous system.

Coagulation disorders in cancer

Coagulation disorders are common in cancer patients. This article reviews the coagulation laboratory findings in these patients and the thromboembolic and hemorrhagic manifestations of malignancy. Among the many topics addressed are Trousseau's syndrome, disseminated intravascular coagulation, and acquired von Willebrand disease. Pathogenesis of the coagulation disorders and recommendations for treatment of various syndromes are discussed.

Idiopathic acute portal vein thrombosis: a case report

There are few reported cases of acute portal vein thrombosis presenting as an acute abdomen in adolescent age group. Most published series concern chronic extrahepatic portal vein thrombosis. Acute portal vein thrombosis is rare, but can develop into serious complications. Hence, prompt diagnosis and heparinization can prevent the development of lethal complications such as venous gangrene of the bowel and portal hypertension.

Long-term follow-up study of adult patients with non-cirrhotic obstruction of the portal system: comparison with cirrhotic patients

Thirty-two patients with non-cirrhotic portal system obstruction and oesophageal varices of non-malignant etiology were recruited over 13 years. Diagnosis was based on the presence of oesophageal varices at endoscopy, minor alterations in liver function tests and liver histology, a low hepatic venous pressure gradient, and pertinent angiographic patterns. Twenty-three had portal vein thrombosis, nine had splenic vein thrombosis. Twenty-one had idiopathic portal vein obstruction, 11 had secondary obstruction. The outcome was compared with a group of 32 patients with cirrhosis and portal hypertension, matched for age, Child-Pugh class, previous history of gastrointestinal bleeding, and size of oesophageal varices. Patients with non-cirrhotic obstruction of the portal system were followed for up to 171 months (mean 94 months). During follow-up ten patients had gastrointestinal bleeding, and eight died (five of gastrointestinal bleeding). After 6 years of follow-up, the cumulative risk of gastrointestinal bleeding was 24%, the cumulative risk of death was 17%, and the cumulative risk of death from gastrointestinal bleeding was 14%. Cumulative probability of death by any cause and the probability of gastrointestinal bleeding were significantly lower in patients with non-cirrhotic obstruction of the portal system than in patients with cirrhosis comparable for liver function and portal hypertension (p = 0.04 for both). The cumulative probability of death by gastrointestinal bleeding was not significantly different. In conclusion, the prognosis for non-cirrhotic obstruction of the portal system is significantly better than for patients with cirrhosis with comparable levels of liver function impairment and severity of portal hypertension.

Adult "idiopathic" extrahepatic venous thrombosis. Importance of putative "latent" myeloproliferative disorders and comparison with cases with known etiology

The etiology of extrahepatic venous obstruction (EHVO) is unknown in 50% of cases. Recently the presence of a "latent" myeloproliferative disorder has been reported in adults with "idiopathic" EHVO. We evaluated the course of these patients to establish if any putative latent myeloproliferative disorder influenced the clinical course compared to those with a known cause. Among 132 EHVO patients, 78 (59%) had a known etiology, 7 (5%) with an overt myeloproliferative disorder. The "idiopathic" group had 54 patients; 24 (13 men, 11 women) were diagnosed after 15 years of age, (median 38 years, range 17-70) with a median follow up of 96 months (19-372). Only 2 (8%) developed an overt myeloproliferative disorder. These 24 had a similar pattern of bleeding and onset of ascites as those with known cause. In EHVO failure to diagnose a latent myeloproliferative disorder does not influence the course of variceal bleeding, and thus has little prognostic significance.

Hepatic vascular disease and portal hypertension in polycythemia vera and agnogenic myeloid metaplasia: a clinicopathological study of 145 patients examined at autopsy

The pathogenesis of portal hypertension arising in patients with myeloproliferative disorders has been difficult to understand because liver biopsy findings often show minimal changes. It has been suggested that increased splenic blood flow, hepatic infiltration with hematopoietic cells or sinusoidal fibrosis may be important. We have reviewed the autopsy findings and clinical histories of 97 patients with polycythemia vera and 48 patients with agnogenic myeloid metaplasia collected from three institutions and from the Polycythemia Vera Study Group. Cirrhosis was present in seven patients, one of whom had bleeding varices. Esophageal varices were present clinically in 10 patients without cirrhosis (seven polycythemia and three agnogenic myeloid metaplasia). All of these patients had lesions in small or medium-sized portal veins and four had stenosis of the extrahepatic portal vein with histology compatible with organized thrombi. Nodular regenerative hyperplasia occurred in 14.6% and correlated closely with the presence of portal vein lesions. Thirty patients had greater than 500 ml of ascites, seven of these patients also had varices and six of them had hepatic vein thrombosis. Ascites also correlated with hepatic vein disease confined to small intrahepatic branches. No correlation was seen between hepatic hematopoietic infiltration and signs of portal hypertension. We conclude that esophageal varices are common and are almost always associated with portal vein lesions visible by light microscopy. These portal vein lesions, and the secondary effects of nodular regenerative hyperplasia and portal hypertension, are most likely a result of portal vein thrombosis in patients with myeloproliferative disorders.

Deficiency of protein C in patients with portal vein thrombosis

Portal vein thrombosis has been considered idiopathic in 50% of cases reported in adults. Protein C deficiency is a recently described disorder characterized by a predisposition to develop thromboembolic disease. We report the findings in two patients with portal hypertension and bleeding varices due to portal vein thrombosis in whom a deficiency of protein C was present. Both cases were very similar, with a history of recurrent episodes of systemic thromboembolic disease, mesenteric venous thrombosis that required intestinal resection and upper gastrointestinal bleeding from gastroesophageal varices. Portal hypertension as well as portal vein thrombosis were demonstrated. The hematologic work-up revealed a deficiency of protein C. Both patients were subjected to the Sugiura procedure, and anticoagulation was instituted thereafter. At the time of surgery, a liver biopsy was performed, which was reported as "normal." Two years and 3 months, respectively, after surgery both patients are in good condition. We conclude that protein C deficiency should be investigated in all cases of portal vein thrombosis, especially in those with a history of thromboembolic disease elsewhere.