Budd-Chiari Syndrome 

Budd-Chiari syndrome is a rare disorder that results from blood clots that completely or partially block the hepatic veins of the liver. The hepatic vein is the major vein that carries the blood from the liver. The liver, the largest internal organ in the human body, is responsible for many vital physiologic processes. Blood flow through the liver nourishes the liver, carries in substances that the liver will process, and carries away substances that the liver has produced. When the high pressure of blood in these veins is slowed, it can lead to an enlarged liver, and to ascites — an accumulation of fluid or blood in the abdomen. 

What exactly causes Budd-Chiari syndrome is unknown. Most patients with Budd-Chiari syndrome have an underlying condition that predisposes them to blood clotting. About 10 percent have polycythemia rubra vera, a condition in which abnormal amounts of red blood cells are present. Other groups that fall victim to the syndrome are those with sickle cell disease. Still other causes of Budd-Chiari may include certain infections, the use of oral contraceptives, body changes during pregnancy and the postpartum period, phlebitis (inflammation of a vein), injury to the abdomen, and membranous webs. Conditions that can afflict direct pressure on the veins, such as liver abscess, liver cancer, or kidney cancer (which can press directly on the hepatic veins), also increase the chances of developing this syndrome. 

The most common symptom in Budd-Chiari syndrome is ascites with accompanying pain in the upper right-hand portion of the abdomen. Patients can also have abnormal bloods tests indicative of liver disease. Some individuals stricken with the syndrome may be jaundiced, leaving the examining doctor to often first suspect cirrhosis. 

As the liver swells with blood, it becomes tender. The blood accumulation in the liver raises the pressure in the portal vein, but the consequences may not develop for months. One such consequence of this raised pressure is the formation of dilated, twisted (varicose) veins in the esophagus (esophageal varices). These veins may rupture and sometimes massively bleed, ultimately leaving the patient vomiting blood. 

Within a few days to several months, other symptoms of liver failure may occur. The blood clots occasionally extend to block the inferior vena cava — the largest vein entering the heart. This blockage causes swelling in the legs and abdomen. 

Diagnosis of Budd-Chiari syndrome can be explored in numerous ways. One indication is that the liver will present larger than normal. Often an ultrasound of the liver will show abnormalities in the size of the liver and an abnormal pattern of the veins within the liver. X-rays of the veins taken after injection of a radiopaque dye may reveal the precise location of any blockage. Magnetic resonance imaging (MRI) scanning or a liver biopsy may also be used to confirm the diagnosis. A liver biopsy enables the physician to examine cells from the liver. Cells damaged by Budd-Chiari syndrome have a characteristic appearance easily identifiable to a physician. 

Once these abnormalities are confirmed, the key test is the hepatic vein catheterization. In this test, the pressure within each segment of the hepatic vein can be measured. 

Most patients with Budd-Chiari syndrome must have surgery. This entails the surgeon re-routing the blood flow around the clotted hepatic vein into the vena cava. The exact technique will depend upon the specific location of the clots and other factors. In a few patients, a balloon catheter can open the blocked blood vessels, without the need for major surgery. 

Sometimes, anti-clotting drugs can be used for patients with a sudden onset of clotting in the veins of the liver. These drugs do not seem to work when the clots have become established, however. 

Less than one-third of people suffering from Budd-Chiari syndrome survive for one year without prompt and effective treatment. If surgery is done before permanent liver damage sets in, long-term survival is possible. In these cases, damaged liver cells can actually recover. If patients are already very sick with liver disease, the surgery may not be as helpful. 

If esophageal varices develop and bleed, surgery will be performed to reduce the pressure in the portal vein. During this surgery, the portal vein is connected to the inferior vena cava, causing blood flow to bypass the liver. However, this shunt can increase the risk of liver encephalopathy. 

Liver transplantation can be an effective treatment, particularly for people with severe liver failure and those stricken with Budd-Chiari syndrome who have deteriorating liver function and complications. In some cases, however, the underlying condition that caused the syndrome excludes transplantation as a treatment option. 

The best approach to prevention is to carefully control the blood disorders that can lead to Budd-Chiari syndrome. 

Works Cited: 

1. Worman, Howard J. Budd-Chiari Syndrome. Columbia University Medical Center:
 http://cpmcnet.columbia.edu/dept/gi/BC.html. 

2. MERCK Manual Medical Library. Budd-Chiari syndrome. 
www.merck.com/mmhe/sec10/ch138/ch138d.html. 

3. Lampert, Richard H. The Gale Group Inc./Healthline. 
www.healthline.com/gale/Medicine/Budd-Chiari-Syndrome/gem_01_00284.html.  

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