Portals hypertensionK76.6

Pressure increase in the portal vein (v. portae hepatis) >12mm Hg. The increase in pressure is usually the result of cirrhosis of the liver (in industrialized countries), schistosomiasis (in endemic areas) or changes in liver vessels. The consequences are esophageal varices and a possible portosystemic encephalopathy. The diagnosis is based on clinical criteria and on imaging and endoscopic procedures.

Increased portal flow (rare) e.g. arteriovenous fistula

Prehepatic

• Thrombosis of the portal vein (e.g. thrombosis pancreatitis, pancreatic carcinoma, polycythaemia vera, when taking estrogen-containing contraceptives, thrombophilia) Compression syndromes of the portal vein (e.g. due to tumours, lymph nodes)

Hepatic (>90% of cases)

• Praesinusoidal: Idiopathic portal hypertension; other periportal disorders (e.g. myeloproliferative diseases, liver metastases (common cause), sarcoidosis, congenital liver fibrosis; bilharzia (schistosomiasis) - common cause in the tropics!
• Sinusoidal: Cirrhosis (all forms)
• Postsinusoidal: Hepatic sinusoidal obstruction syndrome (hepatic venous occlusive disease)

Posthepatic

• Closure of the hepatic veins (e.g. hepatic vein thrombosis - Budd-Chiari syndrome = closure of the hepatic veins due to thrombosis, tumor compression or congenital occlusion. Obstruction of the inferior vena cava.
• Cardiac ascites (right heart failure, severe heart failure)

The portal vein, formed by the confluence of the superior mesenteric and lienal veins, carries blood from the gastrointestinal tract, spleen and pancreas to the liver. Within the sinusoids, blood from the portal circulation mixes with arterial blood. From the sinusoids, blood is passed through the hepatic veins into the inferior vena cava. The normal portal pressure is 5 to 10 mmHg, which exceeds the pressure in the inferior vena cava by 4 to 5 mmHg (portal venous gradient). Disturbances of the outflow (pre-, intra- or posthepatic) or, more rarely, an increase in blood flow lead to an increase in pressure in the hepatic circulation.

The consequence of chronic persistent portal hypertension are portosystemic collaterals. These reduce the blood flow in the liver (reduced hepatic reserve). In addition, toxic substances from the intestine, bypassing the liver, directly enter the systemic circulation. In the long term, this causes portosystemic encephalopathy.

The venous congestion in the visceral organs leads to venous collateralisation with varicose veins in different organ systems, to ascites formation, splenomegaly and hypersplenism.

Portal hypertension, regardless of its cause, leads to the formation of venous collateralisation (varicose veins). Submucous varices in the distal esophagus (esophageal varices) and also in the gastric fundus can suddenly rupture (danger of life-threatening gastrointestinal bleeding). 1/3 of patients with liver cirrhosis suffer variceal bleeding.

Porto-gastroesophageal collaterals lead to a backlog in the stomach mucosa (portal hypertensive gastropathy); acute or chronic bleeding is possible regardless of the formation of varices.

Visible collaterals in the abdominal wall, starting from the navel region, are called caput medusae. They are rarer and indicate a shunt in the umbilical and periumbilical veins (Note: a caput medusae can only develop in open umbilical veins - only in 1% of cases).

Venous collaterals in the rectal area can cause rectal varices (risk of bleeding).

Portal hypertension itself is asymptomatic. Symptoms and clinical signs are based on the chronic sequelae of venous hypertension. The most dangerous complication is acute varicose vein bleeding. Patients typically experience a sudden painless upper gastrointestinal bleeding, which is often massive. Bleeding due to portal hypertensive gastropathy is often subacute or chronic. Further clinical symptoms are caused by the symptoms of congestion in the various organs, such as splenomegaly and hyperplenia syndrome or ascites.

Clinic; portal hypertension can be assumed if there are signs of collateralization, splenomegaly, ascites or portosystemic encephalopathy in patients with liver cirrhosis

Measurement of portal pressure by duplex sonography (relatively inaccurate). More precise is an invasive measurement using a hepatic vein catheter (WHPV = wedged hepatic vein pressure).

Dilated intra-abdominal collaterals can be detected by sonography or computed tomography. A Doppler ultrasound examination provides information about the patency and flow in the portal vein.

Oesophagogastric varices and portal hypertensive gastropathy are diagnosed endoscopically, as is the presence of a risk of bleeding from varices (e.g. reddened areas on the varices, so-called cherry spots).

treatment of the underlying disease. Long-term treatment of esophageal varices at risk of bleeding consists of rubber band ligatures (so-called varicose vein banding) and sclerotherapy (polidocanol).

Non-selective beta-blockers with or without isosorbide mononitrate: Long-term drug therapy of varicose veins that have bled consists of the administration of beta-blockers; these drugs reduce portal pressure mainly by reducing portal flow (e.g. propranolol: 40-80 mg p.o. 2x/day, Nadolol: 40-160 mg p.o. 1x/day, Timolol: 10-20 mg p.o. 2x/day). The combination with isosorbide mononitrate 10-20 mg p.o. 2x/day can additionally reduce the portal pressure.

In case of an inadequate response to one of the therapies, a transjugular intrahepatic portosystemic shunt (TIPS), or alternatively a surgical portocaval shunt, may be considered. In TIPS, the shunt is created by stent implantation between the portal and hepatic venous blood circulation.

Hypersplenism rarely leads to clinical problems and usually does not require specific treatment.

The mortality rate for acute variceal bleeding is > 50%. The prognosis is determined by the extent of the hepatic reserve and bleeding. In survivors, there is a risk of bleeding recurrence within the next one to two years of 50 to 75%. Controlled permanent, endoscopic or drug treatment reduces the risk of bleeding, but has only a marginal effect on long-term mortality.

1. Bloom S et al (2015) Portal hypertension: pathophysiology, diagnosis and management. Internal Med J 45:16-26.
2. Classen M et al (2008) Repetitorium Internal Medicine. Urban&Fischer Publisher Munich S 279
3. Hahn JM (2013) Checklist Internal Medicine. Georg Thieme Publishing House, Stuttgart S 424-426
4. Pillai AK et al (2015) Portal hypertension: a review of portosystemic collateral pathways and endovascular interventions. Clin Radiol 70:1047-1059.
5. Schouten JN et al (2015) Idiopathic non-cirrhotic portal hypertension: a review. Orphanet J Rare Dis 10:67.