Primary achalasia is a motility disorder with yet undiscovered etiology that is thought to be either viral, autoimmune or neurodegenerative.^[1] The incidence of achalasia is 1.63/100,000, therefore, it is considered a rare disease.^[2] It results from progressive degeneration of ganglion cells in the myenteric plexus in the esophageal wall, leading to failure of relaxation of the lower esophageal sphincter (LES).^[3] Thus, the proposed treatments aim to reduce the pressure of LES, namely pharmacologic agents, pneumatic dilation and endoscopic and surgical myotomy.^[1] For the past decade, peroral endoscopic myotomy (POEM) has proven to have excellent results and can be now considered treatment of choice in the countries where it is performed.^[4]

This is a retrospective study on the initial five patients we performed POEM on - four males and one female. All of them had symptoms of dysphagia and retrosternal pain, as well as weight reduction. Their symptoms were graded according to the Eckardt scoring system, as it is the most frequently used one when it comes to achalasia.^[5] The subjects were diagnosed via barium swallow and upper digestive endoscopy, as esophageal manometry was not available to perform.

The procedure was performed under general anesthesia and the patients were placed in supine position. A forward-viewing endoscope with a transparent distal cap was used. At the beginning, the distance between the dentition and the cardia of every subject was measured. After injecting a high molecule solution of adrenaline, gelofusine and Indigo Carmine, linear incision was positioned on the front wall of the esophagus, approximately at two o’clock, between eight and seventeen centimeters proximal of the gastroesophageal junction (GEJ). Submucosal tunnel was created from there to two centimeters distal of the GEJ, onto the gastric cardia. Once the submucosal tunnel was completed, full-thickness myotomy of the lower esophageal sphincter was performed, followed by one to two centimeters myotomy in the cardia. The tunnel was sealed with Endoclips only after the relaxation of the LES was verified. On the following day, new upper GI series were ordered, this time with peroral ingestion of urografin to confirm once again the success of the procedure and lack of perforation.

None of the subjects had severe adverse events in the early post-procedural period. In all of them subcutaneous emphysema was observed which resorbed by itself in the next couple of days. In one of the cases, classified as type III achalasia, necrosis of the mucosa occurred about 28 days after the POEM.

The subjects were endoscopically controlled at two months and at one year after the procedure. One had mild reflux and another one did not comply with the endoscopic follow-up program but kept in touch and did not report any residual symptoms. Furthermore, their symptoms, if any, were once again graded according to the Eckardt system. The comparison between the preprocedural and postprocedural score showed excellent results in relieving the symptoms.

The POEM procedure was first performed on humans in 2008 by Inoue et al.^[6] Since then, it has gained traction and has become widely used for the treatment of achalasia. Nowadays, there are meta-analyses comparing it to the Heller myotomy. They include thousands of patients^[7] and studies, where follow-ups are performed for up to 10 years^[8]. In a randomized controlled trial, comparing POEM to Heller myotomy, clinical success at the two years follow-up was observed at 83% of the POEM group and at 81.7% of the surgical myotomy group. When compared, serious adverse events occurred in 2.7% of the subjects after the POEM and in 7.3% after the laparoscopic myotomy.^[9]

Moreover, when measuring clinical outcomes of POEM and pneumatic dilatation (PD), the second most used endoscopic technique for treatment of achalasia, the patients that underwent POEM showed significantly better short- and long-term outcomes.^[10]

Since fundoplication is not performed along with POEM, as it is with Heller myotomy, the development of gastroesophageal reflux disease was a major concern. Studies show that the frequency of GERD differs according to the method used for its diagnosis – symptom development, pH monitoring and endoscopic findings.^[8,9,11] Ultimately, while the risk of GERD is higher with POEM, overall rate of severe erosive esophagitis is low.^[12]

Per-oral endoscopic myotomy is a safe, minimally-invasive procedure, that shows excellent clinical outcomes and symptoms reduction when used for the treatment of achalasia. It can be used as a therapy of choice, compared to the Heller myotomy and pneumatic dilatation.