Achalasia: From Bench to Peroral Endoscopic Myotomy.

Achalasia is a primary esophageal motility disorder with an estimated annual incidence of 1 per 100,000 persons. It is characterized by the absence of esophageal peristalsis and failure of the lower esophageal sphincter (LES) to relax upon swallowing, resulting in progressively severe dysphagia for solids and liquids, regurgitation, aspiration, chest pain and weight loss. Achalasia results from a loss of enteric neurons, most likely due to an autoimmune reaction in patients with a particular immunogenetic background. To date, 3 manometric subtypes have been identified based on high resolution manometry. To what extent these subtypes also indicate differences in underlying pathophysiological mechanisms is however unclear. As achalasia cannot be cured, treatment is confined to disruption of the LES to improve bolus passage and thereby relieving symptoms. The 2 most commonly used treatment modalities available for this purpose include pneumodilation and laparoscopic Heller myotomy. Both treatments have been shown repeatedly to be successful; however, success rates decline in time, most likely due to progression of the disease. A recent European randomized trial provides objective data indicating that both treatments are equally effective. In view of these data and the low incidence of the disease, the choice between these 2 treatments should be based on the expertise and experience available. Recently, excellent short-term success rates have been reported with a new endoscopic technique, that is, peroral endoscopic myotomy. However, longer follow-up data are absolutely needed before accepting this technique as a new treatment option for achalasia in clinical practice.