Portal hypertension is increased portal vein pressure over the normal pressure of 5-8 mm Hg. As the portal pressure rises above 10-12 mm Hg, collateral veins between the portal and the systemic venous system dilate. Thus an attempt is made by the body to reduce the portal venous pressure.

The main sites are gastro-esophageal junction, rectum, diaphragm, left renal vein, retroperitoneum and the anterior abdominal wall via the umbilical vein.

Causes

Pre-hepatic

The cause of obstruction is before the venous blood enters liver

• Portal vein thrombosis

Hepatic:

The obstruction is in the liver itself

• Cirrhosis of liver
• Non-cirrhosis portal fibrosis
• Schistosomiasis
• Sarcoidosis
• Arteriovenous fistulae
• Primary biliary cirrhosis
• Toxic- Vinyl chloride, copper, arsenic etc.

Post-hepatic:

The obstruction is in the system after blood leaves the liver towards the heart

• Budd Chiari syndrome
• Veno-occlusive disease
• Constrictive pericarditis
• Right sided heart failure

Clinical Features

• Splenomegaly
• Hematemesis and melena
• Ascites
• Encephalopathy