The function of the esophagus (food tube) is to transport food from the mouth to the stomach. Synchronized (peristaltic) contractions follow each swallow to accomplish this task. Between swallows, the esophagus usually does not contract.
The lower esophageal sphincter (or LES) is a muscle that separates the esophagus from the stomach. It acts like a valve that normally stays tightly closed to prevent contents in the stomach from backing up into the esophagus. When we swallow, the LES opens up (the muscle relaxes) so that the food we swallow can enter the stomach.
Difficulty swallowing liquids or solids, heartburn, regurgitation, and atypical (or non-cardiac) chest pain may be symptoms of an esophageal motility disorder.
Examples of motility disorders of the esophagus that are described below include gastroesophageal reflux disease (GERD), dysphagia, achalasia, and functional chest pain.
Gastroesophageal reflux disease (GERD)
The most common symptom that occurs in the esophagus is heartburn. It happens when stomach contents washes up into the esophagus repeatedly (gastroesophageal reflux) and irritates the lining of the esophagus. This occurs when the lower esophageal sphincter (LES) does not work properly.
This can be due to a weak sphincter muscle, too-frequent spontaneous relaxations of the sphincter, or hiatal hernia. Hiatal hernia means that the stomach pushes up into the chest above the sheet of muscle that separates the abdomen from the chest (this muscle sheet is called the diaphragm). A hiatal hernia weakens the sphincter.
Dysphagia means ineffective swallowing. Sometimes this occurs when the muscles of the tongue and neck that push the food into the esophagus are not working properly because of a stroke or a disease affecting the nerves or muscles.
However, food can also stick because the lower esophageal sphincter does not relax to let the food into the stomach (a disorder called achalasia – see below), or because the esophagus contracts in an uncoordinated way (a disorder called esophageal spasm).
Dysphagia can cause food to back up in the esophagus. Symptoms may include:
- A sensation of something getting stuck
- A sensation of pain
This condition is diagnosed when there is a complete lack of peristalsis within the body of the esophagus. In addition, the lower esophageal sphincter does not relax to allow food to enter the stomach.
Most people with achalasia have symptoms for years prior to seeing a physician that may include:
- Difficulty swallowing both liquids and solids
- Weight loss
- Atypical chest discomfort
Functional chest pain
Sometimes individuals have pain in their chest that is not like heartburn (no burning quality) and that may be confused with pain from the heart. Particularly if you are over 50 years of age, your doctor will always want to first find out if there is anything wrong with your heart, but in many cases the heart turns out to be healthy.
In many people with this kind of pain and no heart disease, the pain comes from spastic contractions of the esophagus, or increased sensitivity of the nerves in the esophagus, or a combination of muscle spasm and increased sensitivity.
Adapted from IFFGD Publication: Gastrointestinal Motility Disorders of the Esophagus and Stomach by William E. Whitehead, PhD, Co-Director, Center for Functional GI & Motility Disorders Center; Professor of Medicine, Division of Digestive Diseases; and Professor of Psychology, University of North Carolina, Chapel Hill, NC, and IFFGD Publication: Other Esophageal Motility Disordersby Barry W. Jaffin, MD, Department of Gastroenterology, Mount Sinai Medical Center, New York, NY.