What causes portal hypertension?
Any condition or abnormality that changes the blood flow, and therefore the pressure within the vessels, can cause hypertension. The cause of the increased pressure in the portal venous system may be above the liver (suprahepatic), within the liver (hepatic) or below the liver (infrahepatic), and may include cardiac disease, hepatic vein thrombosis (Budd-Chiari syndrome), cirrhosis and arteriovenous malformations (AVMs) within the splenic vasculature.
What are the symptoms of portal hypertension?
Gastrointestinal bleeding with a low platelet count may be the first symptom of portal hypertension. Depending on the severity of liver disease, symptoms may also include ascites (fluid collection in the abdominal cavity), jaundice, hepatic encephalopathy, coagulopathy (slow clotting), or spider angiomata. The patient may also have an enlarged liver (hepatomegaly) or spleen (splenomegaly).
How is portal hypertension diagnosed?
Clinically, portal hypertension is diagnosed in the presence of end-stage liver disease with ascites and/or varices. Subclinical cases are more difficult to diagnose. Imaging studies are helpful in diagnosing portal hypertension as they define the portal venous anatomy. Doppler ultrasonography is a noninvasive technique and offers good information on the venous blood flow. Magnetic resonance imaging (MRI) and computed tomography (CT) may also provide valuable information. Pressure measurement of the portal system is possible, but it is invasive and usually not practical.
What is portal hypertension?
Portal hypertension is a term for elevated pressures in the blood vessels that drain the intestinal tract and spleen into the liver (portal circulation). These increased pressures lead to dilations of the vessels called varices. Depending on the severity of liver disease and/or portal hypertension, varices may develop in the esophagus and in the stomach.
What are varices?
Varices are blood vessels that have dilated due to higher pressure. They appear similar to varicose veins. These dilated and out-pouched vessels are prone to bleeding because the vessel walls are weakened from increased pressure. Larger varices have thinner walls and are more prone to bleed.
Will I need an endoscopy?
Endoscopy is indicated in cases of a gastrointestinal bleed. It is performed as soon after an upper GI bleed as possible, ideally within 12 hours or when the patient is stabilized. Varices are visible in the esophagus as long bluish bulging columns along the surface of the esophagus. Large varices are either ligated with elastic bands to cut off circulation to the vessel or injected with a sclerosing agent.
What is the treatment for portal hypertension?
The goal of therapy for portal hypertension is to decrease portal pressures. Medical management may include the use of beta-blockers (such as propranolol) to decrease portal resistance and to decrease the risk of variceal bleeding. Vasopressin or somatostatin may be used in an acute bleeding episode. Beta-blockers and vasopressin have powerful systemic effects and may not be the best choice due to adverse cardiac or circulatory effects. Somatostatin (octreotide) is more specific to the portal circulatory system and is safer.
Endoscopic therapy is effective in episodes of gastrointestinal bleeding to ligate (band) or inject varices with sclerosing agents. During an acute variceal bleed, the vessels may be tamponaded with pressure from an inflated balloon, though this is rarely required.
Shunting or stenting procedures may be performed to change the blood flow and thereby decrease portal pressure. Transjugular intrahepatic portal systemic shunting is a nonsurgical, radiological procedure. Surgical shunts may also be used to reduce venous pressure and to maintain hepatic and portal blood flow.
Liver transplantation is the most effective treatment for liver disease. There are many considerations in the allocation of scarce human cadaver donors. Depending on the severity of liver disease or liver failure, patients are placed on a list in priority of need.
Does portal hypertension have a genetic or hereditary link?
No. Portal hypertension is the result of structural changes within the liver that cause increased resistance in blood flow and increased pressure within the vessels.
What is cirrhosis of the liver?
Cirrhosis is a chronic degenerative disease of the liver in which the organ becomes fibrotic with changes in the cells and connective tissue. The result is a loss of liver function and an increase in resistance to the flow of blood through the liver. Some causes of cirrhosis include alcoholism, hepatitis, cholestatic liver disease, hemochromatosis and drug-induced liver disease.
What is Budd-Chiari syndrome?
Budd-Chiari syndrome is a disorder in which blood clots (thrombosis) develop in hepatic veins. These clots increase the pressure in the portal circulation, leading to portal hypertension. This syndrome may be associated with abdominal trauma; clotting deficiencies; tumors of the pancreas, kidneys or adrenal glands; hepatocellular carcinoma; lupus; oral contraceptives; or may be without a known cause (idiopathic).
The symptoms of Budd-Chiari syndrome include ascites, abdominal pain, hepatosplenomegaly (enlargement of the liver and spleen), jaundice, hepatic encephalopathy and variceal bleeding.
What is hepatic encephalopathy?
Hepatic encephalopathy is a reversible dysfunction of the brain that stems from liver disease. Clinically, symptoms can vary from subtle personality changes to deep coma.
What is hepatorenal syndrome?
This is a complication in patients with liver disease or cirrhosis and ascites. The kidneys fail secondary to constriction of the blood vessels supplying them.