Corpus: Portal hypertension

Portal hypertension is when the pressure in the portal vein increases to over 12 mmHg (normal approx. 5 to 10 mmHg).

Portal hypertension can be classified according to the localisation of the cause:

• prehepatic
  • arterioportal fistula
  • portal vein thrombosis
  • Compression due to neoplasia (e.g. pancreatic head carcinoma)
• intrahepatic
  • Fatty liver
  • Liver cirrhosis
  • occlusion of intrahepatic veins
  • schistosomiasis
• posthepatic
  • Budd-Chiari syndrome
  • right heart failure

Liver cirrhosis is the most common cause of portal hypertension.

In the presence of portal hypertension, the flow resistance in the hepatic stroma is increased. Proper drainage of blood and lymph from the liver is no longer guaranteed.

In an endeavour to maintain the circulation, the organism makes increased use of the portocaval anastomoses between the hepatic and systemic circulation, which under normal circumstances are unused. This leads to the development of typical complications:

• Abdominal wall varices (caput medusae, Cruveilhier-Baumgarten syndrome)
• oesophageal varices (porto-gastro-oesophageal collaterals)
• Fundus varices
• Anorectal varices (mesenteric-hemorrhoidal collaterals)

Another serious complication of portal hypertension is the accumulation of fluid in the abdominal cavity, known as ascites.

The congestion of blood in the hepatic stroma leads to moderate splenomegaly due to a backlog in the portal circulation. The prolonged retention time of the congested blood in the spleen leads to an increased breakdown of thrombocytes, which manifests itself in the form of thrombocytopenia.

The failure of the liver to detoxify the blood leads to the development of hepatic encephalopathy if portal hypertension persists for a long time, as toxic ammonia, for example, reaches the brain unhindered via the systemic circulation.

Increased lung perfusion can also lead to portopulmonary hypertension.

The diagnosis of portal hypertension is based on the patient's medical history, physical examination and typical complication-related symptoms. Sonography or Doppler sonography is suitable for visualising possible vascular anomalies in the liver.

• MDS Manuals - Portal hypertension, retrieved on 21/11/2022
• Avalos L. The role of the transjugular intrahepatic portosystemic shunt in the management of patients with liver cirrhosis - experiences from a tertiary centre, dissertation, 2022