Hiatal hernia is the protrusion of a portion of the stomach into the chest cavity through a natural opening in the diaphragm (between the abdomen and the chest cavity).

This condition can interfere with a sphincter (muscle) that prevents the backflow (reflux) of stomach acid into the esophagus. People with hiatal hernias may also have gastroesophageal reflux disease (GERD), a condition marked by the reflux of acid into the esophagus. Hiatal hernias are common, and are associated with increasing age (especially in people over 50) and increasing weight. In addition, women are more prone to hiatal hernias than men.

There are several different types of hiatal hernias including sliding hiatal hernia, paraesophageal hiatal hernia and diaphragmatic hernia (due to birth defect or trauma).  

It is unclear why most hiatal hernias develop. The association of age and weight may be related to the gradual slippage of the stomach into the chest and the cumulative effect of increased pressure within the abdomen over time.

Most hiatal hernias do not cause symptoms. However, people with hiatal hernias and GERD may experience heartburn, difficulty swallowing and chest pain.

Hiatal hernias may be diagnosed by a physician with a physical examination that follows a medical history. The symptoms may lead a physician to perform a barium x-ray and/or endoscopy to confirm the presence of a hiatal hernia.

Treatment for GERD and hiatal hernias varies but may include lifestyle changes (e.g., losing weight) or medications (e.g., antacids, H2 blockers and proton-pump inhibitors). In severe cases, surgery to strengthen the sphincter and/or pull the stomach back into the abdomen may be performed. These procedures may include thoracotomy, laparotomy or laparoscopic surgery.

Hiatal hernias cannot usually be prevented, but there are ways to prevent the gastroesophageal reflux that often accompanies them, such as avoiding foods and drinks that aggravate reflux, elevating the head of the bed and quitting smoking.