The lower part of the oesophagus (food pipe) where it joins the stomach is normally configured to only allow food to go one way – into the stomach. It achieves this by various mechanisms such as a lower oesophageal sphincter and the shape of the top of the stomach, and prevents acid from travelling back up into the oesophagus.
Gastro-oesophageal reflux disease, or GORD, is a condition where these mechanisms fail, and the stomach acid refluxes back into oesophagus and causes irritation. This causes burning discomfort in the chest, called ‘heartburn’. This may be worse when lying down, and is relieved by anti-acid medications such as Nexium or Pariet. In severe cases food may even regurgitate back up into the throat. Conditions such as asthma or chest infections may be worsened as some of the acid that comes up may travel down the windpipe into the lungs.
Another part of the anti-reflux mechanism is the hiatus of the diaphragm. The diaphragm is a large sheet of muscle which separates the lungs from the abdomen and the hiatus is the opening through which the oesophagus enters the stomach. This may become weakened and enlarged so that part of the stomach, which normally sits entirely in the abdomen, may protrude up into the chest – hiatus hernia. Sometimes, other organs such as the small or large bowel may even go up into the hernia as well.
A hiatus hernia is often associated with reflux and therefore we consider the two conditions to be related.