Path Notes: Portal Hypertension*****

Question 1

What are the three ways to classify Portal Hypertension?

Answer 1

1. Pre-Hepatic: Obstructive thrombosis of the portal vein
2. Hepatic: Liver Cirrhosis
3. Post-Hepatic: Severe RHF, Hepatic vein outflow obstruction, Constrictive Pericarditis

Question 2

What causes Hepatic-type Portal Hypertension, arising from Cirrhosis?

Answer 2

Perivenular scarring causes increased resistance to portal flow, both at the level of the sinusoids and of the terminal hepatic veins.

Anastomoses form (angiogenesis) between the arterial and portal systems, within the fibrous septa (but these of course bypass the parenchyma)

Question 3

What are the three main (direct) clinical consequences of portal hypertension? (Just name them)

Answer 3

1. Ascites
2. Formation of Porto-systemic venous shunts
3. Congestive Splenomegaly

Question 4

What is involved in ascites, due to portal hypertension?

Answer 4

Ascites is a collection of fluid in the peritoneal cavity - becomes detectable at ~500ml

Other things that can contribute to ascites:

• Hypoalbuminaemia
• Hepatic Lymph
• Intestinal Fluid Leakage
• Renal retention of water and sodium secondary to hypoaldosteronism

Question 5

What is involved in Porto-systemic venous shunts due to portal hypertension?

Answer 5

Oesophageal/gastric varices - seen in 65% of patients with advanced cirrhosis. Can result in massive haemetemesis.

(varices = abnormally dilated blood vessel - due to overload)

Rectal shunts

Adbonimal skin - caput medusae - from umbilical veins

Retroperitoneal vessels

Question 6

What is involved in congestive splenomegaly?

Answer 6

Might see hypersplenism - thrombycytopaenia, etc.