A hiatal hernia is when the upper portion of the stomach protrudes through a tear in the diaphragm into the chest. Often, there are no symptoms of a hiatal hernia, but it can cause vomiting, dull chest pains, acid reflux, and pressure on the vagus nerve.
A hiatal hernia is most often caused by straining during bowel movements, heavy lifting, or hard coughing. It can also occur as a result of pregnancy, heredity, or stress. In most cases, no treatment for a hiatal hernia is needed, but stomach surgery may be considered for patients with severe acid reflux.