Recommended therapies for esophageal achalasia are endoscopic pneumatic dilation and Heller-Dor surgical myotomy. Endoscopic myotomy has been recently proposed in human patient in expert centers in Japan, US and Germany. In theory, endoscopic myotomy is as effective as surgical myotomy but less invasive and more effective with less complications than endoscopic pneumatic dilation. Up to now, published studies have confirmed these expectations, with 100% efficacy and no clinically significant complications. The present clinical trial with study the security and efficacy of peroral endoscopic myotomy in primary achalasia patients.