(See also Overview of Vascular Disorders of the Liver Overview of Vascular Disorders of the Liver The liver has a dual blood supply. The portal vein (which is rich in nutrients and relatively high in oxygen) provides two thirds of blood flow to the liver. The hepatic artery (which is oxygen-rich)... read more .)
Etiology of Portal Vein Thrombosis
Common causes vary by age group (see table Common Causes of Portal Vein Thrombosis Common Causes of Portal Vein Thrombosis* Portal vein thrombosis causes portal hypertension and consequent gastrointestinal bleeding from varices, usually in the lower esophagus or stomach. Diagnosis is based on ultrasonography. Treatment... read more ).
Symptoms and Signs of Portal Vein Thrombosis
Acute portal vein thrombosis is commonly asymptomatic unless associated with another event, such as pancreatitis Overview of Pancreatitis Pancreatitis is classified as either acute or chronic. Acute pancreatitis is inflammation that resolves both clinically and histologically. Chronic pancreatitis is characterized by histologic... read more (the cause), or another complication, such as mesenteric venous thrombosis. Most often, clinical features—splenomegaly (especially in children) and variceal hemorrhage—develop over a period of time secondary to portal hypertension Portal Hypertension Portal hypertension is elevated pressure in the portal vein. It is caused most often by cirrhosis (in developed countries), schistosomiasis (in endemic areas), or hepatic vascular abnormalities... read more . Ascites is uncommon (10%) in pre-sinusoidal portal hypertension. Ascites Ascites Ascites is free fluid in the peritoneal cavity. The most common cause is portal hypertension. Symptoms usually result from abdominal distention. Diagnosis is based on physical examination and... read more may be precipitated when cirrhosis Cirrhosis Cirrhosis is a late stage of hepatic fibrosis that has resulted in widespread distortion of normal hepatic architecture. Cirrhosis is characterized by regenerative nodules surrounded by dense... read more is also present or when serum albumin (and thus oncotic pressure) deceases after high-volume fluid resuscitation for a major gastrointestinal bleed.
Diagnosis of Portal Vein Thrombosis
Portal vein thrombosis is suspected in patients with the following:
Mild abnormalities in liver function or enzymes plus risk factors such as neonatal umbilical infection, childhood appendicitis, or a hypercoagulability disorder
Doppler ultrasonography Doppler ultrasonography Imaging is essential for accurately diagnosing biliary tract disorders and is important for detecting focal liver lesions (eg, abscess, tumor). It is limited in detecting and diagnosing diffuse... read more is usually diagnostic, showing diminished or absent portal vein flow and sometimes the thrombus. Difficult cases may require MRI or CT with contrast. Angiography may be required to guide shunt surgery.
Treatment of Portal Vein Thrombosis
For some acute cases, thrombolysis
Management of portal hypertension and its complications
In acute cases, thrombolysis is sometimes successful, best reserved for recent occlusion, particularly in hypercoagulable states. Anticoagulation does not lyse clots but has some value for long-term prevention in hypercoagulable states despite the risk of variceal bleeding Varices Varices are dilated veins in the distal esophagus or proximal stomach caused by elevated pressure in the portal venous system, typically from cirrhosis. They may bleed massively but cause no... read more . In neonates and children, treatment is directed at the cause (eg, omphalitis, appendicitis). Otherwise, management is directed at the portal hypertension Portal Hypertension Portal hypertension is elevated pressure in the portal vein. It is caused most often by cirrhosis (in developed countries), schistosomiasis (in endemic areas), or hepatic vascular abnormalities... read more and its complications; treatment can include octreotide IV (a synthetic analog of somatostatin) and endoscopic banding to control variceal bleeding and nonselective beta-blockers to prevent rebleeding. These therapies have decreased the use of surgical shunts (eg, mesocaval, splenorenal), which can become occluded and have an operative mortality rate of 5 to 50%. Transjugular intrahepatic portosytemic shunting (TIPS) has a limited role in the treatment of portal vein thrombosis Treatment Portal vein thrombosis causes portal hypertension and consequent gastrointestinal bleeding from varices, usually in the lower esophagus or stomach. Diagnosis is based on ultrasonography. Treatment... read more (see  Treatment reference Portal vein thrombosis causes portal hypertension and consequent gastrointestinal bleeding from varices, usually in the lower esophagus or stomach. Diagnosis is based on ultrasonography. Treatment... read more ).
Valentin N, Korrapati P, Constantino J, et al: The role of transjugular intrahepatic portosystemic shunt in the management of portal vein thrombosis: A systematic review and meta-analysis. Eur J Gastroenterol Hepatol 30(10):1187-1193, 2018.
Causes of and risk factors for portal vein thrombosis include umbilical cord infection (in neonates), appendicitis (in children), and hypercoagulability states (in adults).
Suspect portal vein thrombosis if patients have manifestations of portal hypertension in the absence of cirrhosis or if they have mild, nonspecific liver abnormalities plus risk factors.
Confirm the diagnosis using Doppler ultrasonography or, if results are inconclusive, MRI or CT with contrast.
Treat the cause of portal vein thrombosis and the complications of portal hypertension.