This ASG video tip is brought to you by an educational grant from Braintree, a part of Cibela Pharmaceuticals, makers of SUTAB. POEM has become a widely accepted first-line therapy for the treatment of achalasia. Data is emerging on its efficacy as a salvage therapy for recurrent or persistent problems after prior Heller myotomy, which may have a long-term failure rate of 5-15%. The benefit of POEM in this scenario is that a repeat myotomy can be performed in a different orientation from the anterior location of the Heller myotomy. Frequently, the approach for POEM is on the posterior side of the esophagus. Early data has shown salvage POEM after Heller to be safe and effective. However, POEM may be more technically challenging due to the presence of a fundoplication and fibrosis at the level of the GE junction. The most common adverse event reported in POEM after Heller myotomy is mucosal injury. Our case involves a 33-year-old male with a history of symptomatic type 2 achalasia treated by Heller myotomy with door fundoplication 33 months prior to presentation. The patient's onset of symptoms, which included solid and liquid dysphagia with regurgitation, began 12 months prior to the Heller myotomy. The patient felt incomplete improvement of symptoms after the surgery and then had complete recurrence of symptoms five months post-op. He underwent multiple EGD dilation procedures to 20-millimeter diameter with his local gastroenterologist with limited and transient benefit. The patient reported no acid reflux symptoms. A repeat barium esophagum showed a severely dilated and redundant distal esophagus with narrowing at the GE junction and retention of contrast in a barium tablet in the distal esophagus. The patient's ECCARD score at the time of presentation to our clinic was 6. After discussion with the patient regarding the risks, benefits, and alternative therapies, the decision was made to proceed with a salvaged POEM to treat his persistent achalasia symptoms. Initial evaluation of the esophagus showed a sigmoid, dilated esophagus with a blown-out appearance of the lateral wall. Retroflex view revealed a prior surgical fundoplication. The mucosotomy and tunnel formation were performed on the posterior aspect of the esophagus. Submucosal dissection was performed in the usual fashion using a multifunctional electrocautery injection knife using precise cut settings to tunnel through the lower esophageal sphincter into the gastric cardio. Submucosal fibrosis was encountered during the tunneling process. Completion of the tunnel was confirmed by passing across the LES, visualization of large gastric vessels, and retroflex view from the stomach showing submucosal injection. Reentering the tunnel proved to be technically challenging due to severe dilation of the esophagus and significant torque required on the endoscope to reenter the tunnel. Eventually the tunnel was reentered and the myotomy was commenced. Full thickness myotomy was performed for the majority of the length of the tunnel. Submucosal fibrosis was found in the muscular tissue near the LES. In the region of the LES, surgical suture material was encountered and was transected. In the process of performing the myotomy it was noted that a mucosal perforation was created. This was suspected to have occurred as a result of transection of muscular fibers involved with the fundoplication which led to a mucosal perforation in the gastric cardio on the posterior aspect of the tunnel. A large blood vessel was also noted in this area of the myotomy. Multiple attempts with the coagulation graspers were required to achieve effective hemostasis. After hemostasis was achieved, the myotomy was extended onto the gastric cardio side. After completion of the myotomy, attention was paid to the large mucosal defect injury seen in the tunnel. The defect was large as the endoscope could easily traverse it into the gastric lumen. Attempts to visualize the perforation from the luminal side in forward and retroflex view were not possible. The primary objective at this point in the procedure was to determine a method to close the mucosal defect from inside the tunnel given that visualization was not possible from the luminal side. Also a secondary objective was to minimize leaving of any significant foreign body material inside the tunnel if possible. Conventional options for closer consideration at this point included through the scope clips, over the scope clips, and endoscopic suturing. Because of the large metallic footprints that would be left in the tunnel with through the scope clips and over the scope clips, these options were decided against. The optimal strategy would be endoscopic suturing from inside the tunnel, however due to extreme difficulty advancing even a standard upper endoscope into the tunnel cavity, the success of advancing a therapeutic endoscope preloaded with an over the scope suturing system seemed unlikely. Therefore, it was decided to use a novel suture based intramuscular enhanced fixation device that could be employed through the standard endoscope from inside the tunnel and leave a minimal foreign body footprint. Four barbed helical tacks connected by a polypropylene suture and cinch system were inserted circumferentially into the muscular tissue around the mucosal defect from inside the tunnel. Attention was paid to make sure each barbed tack had adequate retention force on the grasped tissue. Once the tacks were placed, the suture was retracted and cinched, thus closing the defect. Careful inspection showed significant reduction in the size of the mucosal defect, but the possibility of a persistent small edge that remained tightened. Therefore, a second suture-based intramuscular enhanced fixation system was employed to close the remainder of the defect. The esophageal mucosotomy was closed with standard endoscopic suturing technique. The patient was admitted for overnight observation, and routine water-soluble esophagram the following morning showed no evidence for leak in the esophagus or gastric cardia with adequate passage of contrast across the GE junction. The patient had normal vital signs and no leukocytosis post-op day 1 and was discharged home on a liquid diet and oral antibiotics. Clinical follow-up 3 weeks post-procedure revealed that the patient recovered without any acute events and was experiencing significant improvement of his symptoms with an improved Eckhart's cohort from 6 to 1 while tolerating a solid diet. Learning points from this case include the following. Mucosal perforation can occur on the posterior aspect of the tunnel in the setting of prior heller myotomy due to prior fundoplication. Careful navigation of the muscular fibers at the level of the fundoplication is crucial to avoid mucosal perforation in this area. Visualization of the gastric cardia mucosal injury may be nearly impossible in both the forward view from the esophagus and retroflex view from the stomach given its posterior location in the fundoplication. Novel suture-based fixation devices can be considered to manage mucosal perforations on the gastric side of the LES from inside the tunnel itself.

peroral endoscopic myotomy

POEM

salvage therapy

achalasia

Heller myotomy