hiatal hernia : Hiatal hernia Overview

Hernias occur when one part of the body protrudes through a gap or opening into another part. And although a hernia can theoretically develop almost anywhere, most are in the abdominal area. This includes hiatal hernias — also known as diaphragmatic hernias — which form at the opening in your diaphragm where your food pipe joins your stomach.

Most small hiatal hernias don't cause any problems, and you may never know you have a hiatal hernia unless your doctor discovers it when checking for another condition. But a large hiatal hernia can allow food and acid to back up into your esophagus, leading to heartburn and chest pain. Self-care measures or medications can usually alleviate these symptoms, although very large hiatal hernias sometimes need surgical repair

Signs and symptoms
Most small hiatal hernias cause no problems. But larger hernias may cause heartburn, belching or chest pain when stomach acids back up into your food pipe (esophagus). These signs and symptoms tend to become worse when you lean forward, strain, lift heavy objects or lie down, and they can also worsen during pregnancy.

In rare cases, the part of your stomach that protrudes into your chest cavity may become twisted (strangulated) or have its blood supply cut off, leading to:

Severe chest pain
Difficulty swallowing (dysphagia)
Obstruction of your esophagus

Signs and symptoms
Most small hiatal hernias cause no problems. But larger hernias may cause heartburn, belching or chest pain when stomach acids back up into your food pipe (esophagus). These signs and symptoms tend to become worse when you lean forward, strain, lift heavy objects or lie down, and they can also worsen during pregnancy.

In rare cases, the part of your stomach that protrudes into your chest cavity may become twisted (strangulated) or have its blood supply cut off, leading to:

Severe chest pain
Difficulty swallowing (dysphagia)
Obstruction of your esophagus

http://www.mayoclinic.com/health/hiatal-hernia/DS00099/DSECTION=2