Spastic esophageal motility disorders induced significant symptoms including dysphagia, retrosternal pain and regurgitation. Per oral endoscopic myotomy (P.O.E.M.) is a novel approach to perform myotomy through the esophagus with long submucosal tunnel. This study aimed to investigate the feasibility and safety of P.O.E.M. and translate the techniques from animal study to clinical practice in human.