A person with esophageal varices has abnormally enlarged veins in the lower esophagus and upper part of the stomach.

Esophageal varices are usually caused by liver failure, cirrhosis, or other conditions that result in reduced blood flow through the liver. This causes blood to back-up into veins in the esophagus and stomach forming varices.

The enlargement causes the walls of the veins to stretch and become fragile. Severe gastrointestinal bleeding can occur if the veins rupture. The most common causes of esophageal varices are viral hepatitis and alcoholism, which result in cirrhosis.