Esophageal varices are dilated, tortuous veins which are found mainly in the submucosa of the lower esophagus but which may also appear higher up or extend into the stomach. They develop due to increased pressure in the portal venous system, often as a result of liver cirrhosis. This condition scars and damages the liver, impeding normal blood flow through the portal vein. To compensate, blood seeks alternative pathways, forming fragile new vessels (varices) in the esophagus and stomach. These varices are prone to rupture and can cause massive hemorrhages in the upper gastrointestinal tract and the rectum.
Etiology
Unlike typical blood vessels, these collateral vessels lack elasticity and are easily ruptured, leading to bleeding. Other causes of varices include abnormalities in the splenic vein or superior vena cava, hepatic venothrombosis, portal vein thrombosis (blood clots in the portal vein), severe right-sided heart failure, constrictive pericarditis (thickening and stiffening of the pericardium), hepatic vein obstruction, and chronic alcohol consumption.
Risk Factors:
Several risk factors can trigger hemorrhages from these varices, including muscular exertion, constipation, sneezing, coughing, vomiting, esophagitis, irritation from poorly chewed foods or irritating fluids, reflux of stomach contents, and certain medications.
It is vital to recognize the complexity and potential severity of esophageal varices for prompt medical attention and management to prevent life-threatening complications.
Esophageal varices are enlarged and twisted veins primarily located in the submucosa of the lower esophagus and stomach, posing a significant risk of rupture and severe bleeding.
The primary cause of esophageal varices is portal hypertension, a condition arising from impaired portal venous circulation within a damaged liver.
This impairment causes increased obstruction in the hepatic portal vein, which impairs blood transport from the gastrointestinal system to the liver.
As a result, venous blood from the intestinal tract and spleen seeks alternative routes through collateral circulation. This process involves creating new pathways to redirect blood flow back to the heart's right atrium.
Collateral circulation in the lower esophagus and stomach leads to the development of fragile blood vessels, increasing the pressure in these veins.
This elevated pressure causes the veins to expand and form varices prone to bleeding due to the lack of elasticity.
Other causes of esophageal varices include portal vein thrombosis, right-sided heart failure, hepatic vein obstruction, splenomegaly with increased splenic vein blood flow, and heavy alcohol consumption.
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