Early adverse events of per-oral endoscopic myotomy

Background and Aims: The recently developed technique of per-oral endoscopic myotomy (POEM) has been shown to be effective for the therapy of esophageal motility disorders. Limited information is available about POEM adverse events (AEs). Methods: POEM was performed on 241 patients (58% male; mean age, 47.4 +/- 16.4 years) under general anesthesia over 61 months. The main outcome was the rate of intra-and post-procedural AEs. Post-procedural checks comprised clinical and laboratory examinations and endoscopy, with further follow-ups performed at 3, 6, and 12 months. Results: Of the 241 procedures, 238 were successfully completed (mean procedure time, 100.2 +/- 39.5 min). Reasons for abortion were excessive submucosal fibrosis preventing submucosal tunneling. Three patients had severe procedural-related AEs (SAE rate, 1.2%); 1 case of pneumothorax required intra-procedural drainage, and 2 patients had delayed SAEs (1 ischemic gastric cardia perforation and 1 hemothorax, both leading to surgery). The overall rate of minor AEs was 31.1%, mainly prolonged intra-procedural bleeding (>15 min hemostasis) and defects of the mucosa overlying the tunnel; none led to clinically relevant signs or symptoms. Patients experiencing any AE had a significantly prolonged hospital stay (P = .037) and a trend toward prolonged procedure time (P = .094). Neck/upper thoracic emphysema and free abdominal air were noted in 31.5% and 35.7%, respectively (95.3% drained), but without relevant sequelae. Conclusions: POEM has a low rate of SAEs; minor AEs are more frequent but lack a consistent definition. Therefore, based on our experience and literature analysis, we suggest a classification of AEs for POEM. (Clinical trials registration number: NCT01405417.)