The function of the esophagus is to transport food from the mouth to the stomach. For food to be transported efficiently and correctly, the muscles of the esophagus must coordinate in a very structured fashion to transport food to the stomach while ensuring that the stomach contents do not escape. An esophageal dysmotility disorder is one in which this process has been disrupted. These types of disorders can prevent food from being delivered to the stomach or cause stomach contents to be regurgitated. These problems can lead to esophageal dysmotility symptoms such as chest pain, pain when swallowing or the feeling of a permanent lump in the throat.
Esophageal dysmotility disorders have a wide range of causes and effects. One disorder, called spastic esophageal motility disorder, is caused by an imbalance between nerve pathways that cause esophageal muscles to relax and contract. This imbalance leads to muscle spasms that cause difficulty and pain when swallowing, chest pain and acid reflux.
In the case of esophageal achalasia, the disorder is caused by the inability of the esophageal sphincter muscle to relax. This muscle normally relaxes and tightens in response to certain cues, so that food can pass into the stomach while preventing regurgitation of the contents of the stomach. In achalasia, the constant rigidity of the muscle causes difficulty swallowing food and drink, heartburn, coughing, chest pain and regurgitation of stomach contents, including stomach acid.
Another esophageal dysmotility disorder, called scleroderma, develops as the result of the build-up of scar tissue in the esophagus. Scleroderma is the result of an autoimmune disease in which cells of the immune system attack different cell types in the body, including esophageal cells. Over time, chronic inflammation and irritation lead to the formation of scar tissue. This scar tissue weakens the muscles of the esophagus, causing difficulty and pain when swallowing. As the disease progresses, it can cause chronic acid reflux and increase the risk of esophageal cancer.
Dysmotility disorders of the esophagus are generally incurable. The main objective of treatment is therefore symptom management and relief. Several types of medication can be used for dysmotility treatment, including calcium channel blockers and botulinum toxin. Dietary modifications can help relieve symptoms, and some disorders can be improved with surgery.
The primary medications used to treat esophageal dysmotility disorders such as achalasia are calcium channel blockers. These medications are useful because they make swallowing easier by reducing the strength of muscular contractions, including the sphincter muscle of the esophagus. Another medication option is botulinum toxin, also known as Botox®. This medication prevents strong muscle contractions because it causes partial muscle paralysis. Finally, some antidepressant medications help reduce chronic pain and might be prescribed for people who experience chronic chest pain because of dysmotility disorders of the esophagus.
Some dysmotility disorders can be treated with surgery. In the case of achalasia, the most common procedure is a Heller’s myotomy, in which the sphincter muscle is cut so that it is no longer permanently contracted. This procedure also is performed to treat other types of esophagus dysmotility, including spastic esophageal motility disorder.