There are many different causes of esophageal sphincter pain. One of the most common is gastroesophageal reflux disease. Other causes include diffuse esophageal spasms, a nutcracker esophagus, and a hypersensitive esophagus. Many cases of pain in the esophagus present similar symptoms as heart failure, so a proper diagnosis from a doctor is necessary to rule out heart disease.
One of the most common causes of esophageal sphincter pain is gastroesophageal reflux disease, also called GERD. The lower esophageal sphincter normally remains closed except when allowing food to pass into the stomach in order to prevent stomach acid and food from spilling back into the esophagus. If the sphincter is weakened from overeating, a hiatus hernia, or any other reason, harmful stomach acid can enter the esophagus, causing pain.
Pain in the esophageal sphincter is sometimes caused by esophageal spasms. There are two distinct types of esophageal spasms, including diffuse esophageal spasms and a nutcracker esophagus. The esophagus contracts when healthy and serves to move food down from the throat to the stomach for digestion. Occasionally there are dysfunctions in this system that can cause esophageal pain.
Diffuse esophageal spasms occur when the normal contractions that push down food do not function correctly. This disorder most often presents as several sections of the esophagus contracting at the same time. When the esophagus contracts improperly, food can get stuck in place, unable to move into the stomach, causing pain. The exact cause of this disorder is unknown, but it occurs most frequently in Caucasian adult women. Some theories about the cause of this dysfunction include gastric reflux, a primary nerve or motor disorder, or compression of the blood vessels in the vagus nerve.
A nutcracker esophagus is another cause of esophageal sphincter pain that is very similar to diffuse esophageal spasms. This disorder occurs when the contractions in the esophagus are in the proper sequence to push down food, but the intensity of the contractions is more than two times stronger than normal contractions. The cause of this disorder, like diffuse esophageal spasms, is unknown.
Esophageal hypersensitivity is another possible cause of esophageal sphincter pain. Esophageal hypersensitivity occurs when normal processes in the esophagus trigger abnormal pain sensations. It is caused by a dysfunction in the pain receptors, resulting in a decreased pain threshold. The esophagus contains chemoreceptor nerves, mechanoreceptor nerves, and thermoreceptor nerves, which may be overstimulated, causing pain.