Transoral endoscopic esophageal myotomy based on esophageal function testing in a survival porcine model

BackgroundThe most effective treatment of achalasia is Heller myotomy.ObjectiveTo explore a submucosal endoscopic myotomy technique tailored on esophageal physiology testing and to compare it with the open technique.DesignProspective acute and survival comparative study in pigs (n = 12; 35 kg).SettingUniversity animal research center.InterventionEight acute—4 open and 4 endoscopic—myotomies followed by 4 survival endoscopic procedures.Main Outcome MeasurementsPreoperative and postoperative manometry; esophagogastric junction (EGJ) distensibility before and after selective division of muscular fibers at the EGJ and after the myotomy was prolonged to a standard length by using the EndoFLIP Functional Lumen Imaging Probe (Crospon, Galway, Ireland).ResultsAll procedures were successful, with no intraoperative and postoperative complications. In the survival group, the animals recovered promptly from surgery. Postoperative manometry demonstrated a 50% drop in mean lower esophageal sphincter pressure (LESp) in the endoscopic group (mean preoperative LESp, 22.2 ± 3.3 mm Hg; mean postoperative LESp, 11.34 ± 2.7 mm Hg; P < .005) and a 69% loss in the open procedure group (mean preoperative LESp, 24.2 ± 3.2 mm Hg; mean postoperative LESp, 7.4 ± 4 mm Hg; P < .005). The EndoFLIP monitoring did not show any distensibility difference between the 2 techniques, with the main improvement occurring when the clasp circular fibers were taken.LimitationsHealthy animal model; small sample.ConclusionEndoscopic submucosal esophageal myotomy is feasible and safe. The lack of a significant difference in EGJ distensibility between the open and endoscopic procedure is very appealing. Were it to be perfected in a human population, this endoscopic approach could suggest a new strategy in the treatment of selected achalasia patients.