What causes portal hypertension

Portal hypertension is an increase in the pressure within the portal vein (the vein that carries blood from the digestive organs to the liver). The increase in pressure is caused by a blockage in the blood flow through the liver

 

Portal hypertension

recanalized umbilical vein

What causes portal hypertension

 

Portal hypertension occurs when there is an obstruction of blood flow through the liver, and pressure rises within the portal vein. This obstruction can be intrahepatic (intra=within +hepatic=liver), pre-hepatic (pre=before) or post- hepatic (post=after).Intrahepatic causes of portal hypertension

Intrahepatic causes of portal hypertension include cirrhosis and hepatic fibrosis or scarring. A wide variety of illnesses are implicated as the cause of portal hypertension. Examples include the following:

• Alcohol abuse,
• Hepatitis B and C infections,
• Fatty liver (NASH, non-alcoholic steatohepatitis),
• Wilson's disease, an abnormality of copper metabolism,
• Hemochromatosis (iron overload), excess iron buildup
• Cystic fibrosis
• Primary sclerosing cholangitis, a hardening of the bile ducts
• Biliary atresia, poorly formed bile ducts
• Parasite infections such as schistosomiasis

Pre-hepatic causes of portal hypertension

• Portal vein thrombosis or blood clots within the portal vein
• Congenital portal vein atresia or failure of the portal vein to develop

Post-hepatic causes of portal hypertension

Post-hepatic causes are due to obstruction of blood flow from the liver to the heart and can include:

• Hepatic vein thrombosis
• Inferior vena cava thrombosis
• Restrictive pericarditis, where the lining of the heart stiffens and does not allow the heart to relax and expand when blood returns to it. Causes may include tuberculosis, fungal infections, tumors, connective tissue disorders (for example, scleroderma), and complications from radiation therapy.