The first US experience of peroral endoscopic myotomy with fundoplication. Lessons learned. These are our disclosures. Peroral endoscopic myotomy has become a popular minimally invasive alternative to the surgical gold standard laparoscopic heller myotomy for the treatment of achillesia. Both POEM and HM induce a loss in the lower esophageal sphincter function and thus leave patients However, HM is almost always accompanied by fundoplication to protect against GER, whereas POEM is not typically accompanied by fundoplication. In recent studies, the incidence of postpoem GER ranging from 39 to 58% has been reported. To address the issue of postpoem GER, a novel POEM with fundoplication, termed as POEM-F, was recently described, which mimics the DOR fundoplication. POEM-F involves anterior myotomy followed by retraction and tightening of the anterior wall of the fundus into the myotomy tunnel using a loop ligating device to create a partial fundoplication. A total of 13 patients were included with a mean age of 50. Most patients had type 2 achillesia and the mean BMI was 25 and the mean baseline ECAD score was 8. After a standard anterior full thickness myotomy, we proceeded with fundoplication. Using transillumination as a guide, the muscular defect at the most distal end of the myotomy was carefully enlarged using a coagulation grasper. Extraperitoneal vessels are of a larger caliber than those encountered during standard POEM and thus, care must be taken during this action. Accordingly, we recommend floating the fat to improve the visualization of these vessels and to prevent inadvertent injury to them. This image shows an extraperitoneal blood vessel before and after floating of the fat. The peritoneal lining was then opened and the standard gastroscope was advanced through the peritoneal lining angling upwards and leftwards to reach the anterior surface of the gastric fundus. The stomach was then grasped using grasping forceps and was retracted into the submucosal tunnel to simulate the fundoplication wrap. Wrap formation was continuously monitored using the ultraslim gastroscope. When the wrap was deemed satisfactory, the corresponding spot on the fundus was marked using cautery. A through-the-scope clip was then advanced down the channel of the scope and was used to grasp the tip of a 3 cm loop-ligating device. While we found determination of an adequate wrap and efficient process, the exchange of grasping forceps to a cautery-enhanced device followed by the loop-ligating device carrying through-the-scope clips time-consuming and problematic. In one patient, finding the cautery marking proved difficult as it was covered by fat. Additionally, placement of subsequent clips at the fundus also proved to be difficult due to the intervening fat. Thus, we recommend choosing a position that is far from fat. We also recommend noting the orientation to the liver and the presence and appearance of nearby vessels in the fundic serosa. Finally, the serosa should be abraded to increase visualization. The standard gastroscope carrying the loop-ligating device was then reinserted and the previously marked fundic serosa was identified. In one of our patients, while fixing the loop to the fundic serosa, which is the distal anchoring site, the loop fell off. This can be prevented by slowly opening the clip while maintaining forward pressure and ensuring adequate loop slack. After fixing the loop-ligating device at the fundus using 3-4 clips, the scope was then withdrawn into the tunnel. The proximal part of the loop-ligating device was then fixed to the distal myotomy edge using 3-4 clips. Under direct visualization by the Ultraslim gastroscope, the loop-ligating device was then gradually tightened. Following complete loop closure, the tails of the loop-ligating device were cut using a loop cutter. Of note, the sharp cut ends of the loop-ligating device or the clips can erode through the mucosal lining and into the distal esophagus or the gastroesophageal junction. Thus, to prevent this, the clips should be oriented towards the peritoneal side and the cut ends of the loop-ligating device should be turned and oriented towards the peritoneal side. In our earlier patients, following entry into the peritoneal cavity, a Verest needle was placed in the right lower quadrant to moderate degree of capnoperitoneum. To avoid the placement of a Verest needle, continuously suction the peritoneal carbondioxide using the standard gastroscope. Whenever the scope is within the peritoneal cavity during RAB simulation, marking of the fundus and fixing of the loop at the fundus and then finally before the scope is pulled in the esophageal tunnel for anchoring at the distal myotomy edge. Retroflexed view of the stomach showed the completed anterior partial fundoplication RAB. Finally, standard mucosal incision closure was performed using thru-the-scope clips. This clip shows the sheared mucosal incision. There is an increased risk of shearing with POEMF due to the passage of the loop-ligating device catheter alongside the gastroscope through the esophageal mucosal incision and then into the submucosal tunnel and finally into the peritoneal cavity. To prevent this, we recommend a generous incision at the esophageal mucosa and at the peritoneal lining. Additionally, the catheter should be kept close to the scope by maintaining tension on the loop-ligating device and passage should be performed under direct visualization to prevent inadvertent injury to the surrounding structures. POEMF was technically successful in all but one patient. The mean total procedural duration was 105 minutes and a mean of 55 minutes were required for fundoplication. The mean hospital stay was one day and post-operatively, one patient developed atelectasis and new-onset oxygen requirement, which was managed conservatively and was treated as mild. At the median follow-up of 134 days, the mean ECARD score decreased to 0.2. An intact wrap was seen in 80% of patients and no LA-grade COD esophagitis was noted. Of note, one patient developed abnormal esophageal acid exposure time. In summary, to prevent injury to the extraperitoneal blood vessels, float the fat to improve visualization of the extraperitoneal blood vessels. To prevent the loss of an adequate wrap position, choose a position that is far from the peritoneal fat making it easily visible and note the orientation to the liver and the presence and appearance of nearby vessels in the fundic serosa. Additionally, abrade the serosa to increase visualization. To prevent the loss of the loop while anchoring, slowly open the endoclip while maintaining forward pressure and ensuring adequate loop slack. To prevent erosion of the mucosal lining, orient the endoclip and the cut ends of the loop-ligating device towards the peritoneal side. To avoid using a verres needle, continuously suction peritoneal carbon dioxide using the standard gastroscope. To prevent shearing of surrounding structures, make a generous incision at the esophageal mucosa and at the peritoneal lining. Additionally, the catheter should be kept close to the gastroscope and passage should be performed only under direct visualization. In conclusion, 4MF is safe and technically feasible with excellent short-term outcomes. Greater experience, procedural standardization and the development of dedicated tools is likely to refine this procedure further. Larger prospective studies with longer-term follow-up are critical to further validate this procedure.

POEM-F

minimally invasive alternative

achalasia

post-poem gastroesophageal reflux

DOR fundoplication