Achalasia is the most common primary motor disorder. It is suspected in the early stages of functional dysphagia associated with regurgitation or chest pain, and is confirmed by manometry, which in this case shows esophageal aperistalsis and lack of relaxation of the lower esophageal sphincter. At a more advanced stage, when dysphagia tends to be organic in nature, patients report respiratory symptoms with an impact on their general condition. There...