Achalasia is a word that is generated from the Greek “a” which refers to “without” which is a negation prefix, the verb “Khalasis” which means “relaxation” plus the suffix “ia” which refers to “quality” ; The word achalasia describes a condition, where those muscles that are in the lower part of the esophagus do not relax and make it impossible for food to reach the esophagus. In other words, we can say that achalasia is an alteration that affects the esophagus, which includes a part of the digestive system of human beings and other living beings, made up of a muscular tube of around 30 centimeters that connects the stomach with the pharynx.

This alteration in the functioning of the esophagus consists of a blockage or blockage at its entrance to the esophagus, thanks to the increase in pressure in a valve which is called the lower esophageal sphincter. The main function of the esophagus is to transport food from the mouth to the stomach; therefore, it also has a musculature that provides certain propulsive movements that drive the food bolus and the lower esophageal sphincter valve, in its final part, which expands or opens when we eat food so that it passes, and then closes with the in order to prevent backflow.

It was in the year 1679 that the English physician, a pioneer in his neuroanatomical research, Sir Thomas Willis, discovered achalasia. In the year 1881 von Mikulicz who manifested achalasia as a cardiospasm, in order to expose that the possible symptoms were caused by a functional problem rather than a mechanical problem. Hunt and Rake, in 1929, confirmed that this condition was caused by a failure of the lower esophageal sphincter to relax, so it was called achalasia, which refers to the lack of relaxation.