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Portal hypertension – DR DEACPIMP
Definition
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High blood pressure in the portal system, as a result of increased resistance (in the liver)
Have risk of developing varices, which may haemorrhage
Risk factors
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Alcohol
Cirrhosis
Liver damage (inc. hepatitis, haemochromatosis, Wilson’s disease)
Heart failure
Diabetes
Schistosomiasis
Differential diagnoses
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Peptic ulcer
Gastric cancer
Epidemiology
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Very common in patients with cirrhosis
30% of patients with compensated, and 60-70% of patients with decompensated cirrhosis at
the time of diagnosis also have varices
30% chance of developing varices after 6 years with liver failure
Hepatitis B and C are important causes of cirrhosis worldwide
Countries with high rates of schistosomiasis infection have cirrhosis related to this
More common in men – over 60%
Aetiology
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Increased vascular resistance to blood flow in the portal system
Poisuielle’s Law – resistance is related to radius, viscosity and length
o Is the radius that is affected in portal hypertension, with decreased width of blood
vessels for blood to pass through – leads to ‘backing up’
Can be split into pre-hepatic, intra-hepatic and post-hepatic causes
Pre-hepatic
o Splenomegaly, leading to increased flow from the spleen (overwhelming portal
system)
o Thrombotic obstruction
o Portal vein narrowing before the liver
Intra-hepatic (sinusoids are fenestrated vessels where portal vein and arterial blood meet in
the liver, separated from space of Disse)
o Pre-sinusoidal
 Primary biliary cirrhosis
 Schistosomiasis
 Sarcoidosis
o Sinusoidal
 Cirrhosis
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 Partial nodular transformation (regeneration)
o Post-sinusoidal
 Veno-occlusive disease
 Budd-Chiari syndrome (obstruction of ascending vena cava between liver
and heart)
o Other – architectural change
 Massive fatty change
 Regenerative nodules
Varices – collateral blood flow
o Blood is forced to take another route because pressure and resistance is too high in
portal system
o Use portal-systemic anastomoses – these aren’t usually used
 Oesophageal varices (left gastric vein and oesophageal vein)
 Spleen
 Caput medusae (para-umbilical vein)
 Anal varices (superior and inferior rectal vein anastomosis)
o Extra blood flow causes engorgement, and can cause rupture, leading to
haemorrhage
 Oesophageal varices are of particular concern
Clinical features
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Clinical features relating to cause (eg Dupytron’s contracture, clubbing etc in cirrhosis)
Ascites
Varices, and variceal bleeding (portosystemic shunts)
o Haematemesis
o Malaena
o Haematochezia (passage of fresh blood) – from colonic shunt (anastomosis)
o Caput medusa
o Haemarrhoids (anal varices)
Congestive splenomegaly (also a portosystemic shunt)
Hepatic encephalitis
o Lethargy
o Irritability
o Change in sleep
Pathophysiology
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Cirrhosis/sinusoidal
o Contraction of smooth muscle and myofibroblasts
o Disruption of blood flow by scarring and parenchymal nodules
o Damaged sinusoidal epithelia add to intrahepatic vasoconstriction
 Reduction in NO production
 Release of angiotensinogen (RAAS to increase BP)
o Sinusoidal remodelling between arterial and venous systems causing anastomoses in
fibrous septa imposes arterial pressure on venous system
o Arterial vasodilation (prehepatic) leads to increased blood flow to liver:
hyperdynamic
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Mostly from splanchnic artery  increased venous efflux into portal venous
system
Thought to be a result of increased NO levels
 Increased NO as a result of decrease bacteria clearance in the gut
 Can be a result of decreased activity of mononuclear phagocytes
 Or shunting of blood from portal to systemic circulation 
phagocytic Kupffer cells are bypassed
 Antibiotics can be helpful in portal hypertension because increase
bacteria clearance and therefore NO lowers and blood supply to the
liver reduces
Investigations
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Duplex Doppler ultrasonography
o Portal flow and structural changes
o Surface nodules
o Splenomegaly
o Collateral circulation
CT and MRI in cases where ultrasound is inconclusive
Angiography in cases of bleeding (can also intervene)
PR
Endoscopy for oesophageal varices
FBC
o Anaemia
o Leukopenia
o Thrombocytopenia
LFT
o Elevated AST and ALT
o Elevated bilirubin
o May not show raised enzymes (if liver is ‘burned out’)
o Raised PT and INR
Viral hepatitis serology if cause unknown
Hepatic venous pressure gradient can be measure by inserting a catheter
Management
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Beta blockers for portal hypertension
Some evidence statins might help
Band ligation for oesophageal varices
Transjugular intrahepatic portosystemic shunt (TIPS) for those who don’t respond
to/unsuitable for band ligation
Prognosis
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40% of patients with advanced cirrhosis get oesophageal varices, and 50% of these get
massive haemorrhage and death
Prognosis is poor