Definition and Overview

The portal vein is the blood vessel that carries nutrient-rich blood from the pancreas, gastrointestinal tract, gallbladder, and spleen to the liver. The liver then cleanses the blood by processing nutrients and removing any toxin.

Portal hypertension is one of the most common complications of cirrhosis, a condition characterised by long-term damage to the liver and the transformation of healthy liver cells into scar tissue. Scar tissue blocks the flow of blood through the liver, resulting in abnormally high blood pressure in the portal vein. When this happens, the blood will create a new route back to the heart, causing new blood vessels to open up. These include blood vessels along the lower end of the oesophagus and the wall under the upper part of the stomach, which bypass the liver. This prevents the liver from filtering the blood that circulates throughout the body. This condition can cause considerable illness and if not diagnosed and treated promptly, it can lead to death.

Causes of Condition

Portal hypertension is a common complication of cirrhosis. Certain factors that can contribute to the development of these conditions include the following:

  • Alcoholism

  • Biliary atresia - A medical term used to describe bile ducts that do not have normal openings. The condition, which affects infants, is considered to be life-threatening.

  • Congenital portal vein atresia

  • Cystic fibrosis - A congenital disorder, which complications include liver disease. It is common for children with cystic fibrosis to develop portal hypertension.

  • Fatty liver - Also called steatosis, this condition is characterised by the abnormal buildup of fat in the liver.

  • Hepatic vein thrombosis - Refers to the obstruction of the hepatic veins caused by blood clots.

  • Hepatitis B and C infections

  • Inferior vena cava thrombosis

  • Parasite infections

  • Primary sclerosing cholangitis - A chronic disease that damages the bile ducts.

  • Wilson’s disease - A rare genetic disorder that causes copper poisoning in the body. It commonly damages the brain and the liver.

Key Symptoms

Blood vessels in the stomach and oesophagus can dilate if the blood that is supposed to flow through the portal vein is rerouted to them. The condition, which is called varices, can cause symptoms if the dilated blood vessels rupture and bleed. When this happens, a person will vomit blood or pass blood through his bowels. He will also experience rapid heart rate and lightheadedness. Bleeding from varices can lead to serious complications including shock, pneumonia, kidney or liver failure, sepsis, and coma.

Other key symptoms of portal hypertension include:

  • Ascites - The accumulation of fluid in the abdomen that tends to occur due to long-standing liver disorders. One of its complications is spontaneous bacterial peritonitis, a life-threatening condition that affects up to 30% of patients with cirrhosis.

  • Encephalopathy - A general term used to describe damage to the structure of the brain, causing patients to experience forgetfulness and confusion.

  • Decreased levels of platelets or white blood cell count, which makes a person more vulnerable to infections.

  • An enlarged spleen

Who to See and Types of Treatments Available

Portal hypertension is diagnosed through a thorough physical examination, assessment of the patient’s symptoms, blood tests, and procedures that evaluate mental function. Imaging tests, which include magnetic resonance imaging (MRI), ultrasonography, and computed tomography (CT) scan, can also be carried out to detect ascites and examine blood flow in the portal vein.

Portal hypertension treatment focuses on managing complications and preventing new ones from developing. In order to do so, doctors usually perform the following:

  • Control bleeding with drugs, such as octreotide or vasopressin. These drugs, which can be given intravenously, work by contracting the bleeding veins.

  • Blood transfusion, which prevents patients from experiencing life-threatening hypovolemic shock due to significant blood loss.

  • Vein ligation - Using an endoscope (a thin, flexible tube with a camera on its end), doctors tie off bleeding veins. The procedure involves inserting the endoscope through the mouth and then down to the oesophagus.

  • Reduce pressure in the portal vein with drugs, such as timolol or carvedilol.

  • Paracentesis - The procedure to remove fluid that has accumulated in the abdomen. As the results are usually temporary, the procedure is repeated as needed.

If the patient’s condition does not improve after undergoing treatments mentioned above, a procedure called portosystemic shunting is carried out. Its goal is to connect the portal vein to the hepatic vein to restore blood flow in the liver. By doing so, the pressure in abnormal veins is significantly reduced or totally eliminated. This procedure is effective in controlling bleeding in more than 90% of patients. In cases where the patient does not qualify for the procedure, devascularisation or the removal of the bleeding varices is recommended.

Another treatment option for patients with good liver function is called distal splenorenal shunt procedure (DSRS), which goal is also to reduce pressure in the varices. It involves detaching the splenic vein and attaching it to the left vein of the kidney.

In the case of end-stage liver disease, a patient will require a liver transplant in which the damaged liver is removed and replaced with a new liver from a living or deceased donor. Although the procedure is highly effective, getting a new liver can be very challenging as donated livers are scarce and the waiting list is extremely long. Many patients have to wait for years before they undergo the procedure and have to be hospitalised for the management of the complications of their condition while waiting for their new liver.

The prognosis for patients with portal hypertension depends on several factors including the underlying disease, liver function, and the severity of the complications.

References:

  • Garcia-Tsao G, Sanyal AJ, Grace ND, Carey WD, and the Practice Guidelines Committee of the American Association for the Study of Liver Diseases, the Practice Parameters Committee of the American College of Gastroenterology. Prevention and management of gastroesophageal varices and variceal hemorrhage in cirrhosis. Am J Gastroenterol. 2007 Sep. 102(9):2086-102

  • Seijo S, Reverter E, Miquel R, et al. Role of hepatic vein catheterisation and transient elastography in the diagnosis of idiopathic portal hypertension. Dig Liver Dis. 2012 Oct. 44(10):855-60.

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