WASHINGTON – Natural orifice myotomy significantly improved dysphasia symptoms and significantly reduced lower esophageal sphincter pressure in achalasia patients in a prospective study.
The short-term outcome for the procedure, called peroral endoscopic myotomy (POEM), was excellent, although further study is needed to determine the procedure’s long-term efficacy and to compare it with other interventional therapies, said lead author Dr. Haruhiro (Haru) Inoue at the annual clinical congress of the American College of Surgeons.
To conduct the study, the investigators performed POEM in 17 consecutive patients (7 women, 10 men) with a mean age of 41 years, between September 2008 and December 2009. All had confirmed achalasia, including 12 nonsigmoid and 5 sigmoid cases.
The procedure was successful in all 17 patients. Mean dysphagia symptom scores dropped significantly from 10 to 1.3, while mean resting lower esophageal sphincter pressure also dropped significantly from 52.4 to 19.8. No serious related complications were encountered (Endoscopy 2010;42:265-71).
During a mean follow-up of 5 months, additional treatment or medication was necessary in one patient who developed mild reflux esophagitis, said Dr. Inoue of the Digestive Disease Center at Showa University Northern Yokohama Hospital, Japan.
POEM was done under general anesthesia with positive pressure ventilation at a higher pressure than is usually used, by endoscopic CO2 insufflation.
The surgeons created a submucosal tunnel, starting with a submucosal injection at the level of the mid esophagus. Then, using the triangle-tip knife, they dissected the circular muscle bundle. After confirming the status of the gastroesophageal junction, they closed the mucosal entry site with about five hemostatic clips.
The procedure was performed successfully on patients who had previously undergone balloon dilation or Botox injection, Dr. Inoue said.
Current common treatments for achalasia are medication, Botox injection, balloon dilation, and esophagomyotomy (which requires at least five abdominal incisions for trocar placement).
Most systematic studies of current treatments have found laparoscopic myotomy with fundoplication to be the most effective surgical technique, followed by endoscopic balloon dilation and endoscopic botulin toxin injection.
Dr. Inoue noted that endoscopic myotomy for the treatment of achalasia previously was reported in a case series published in 1980, in which a modified needle knife was used to dissect the muscle layer directly through the mucosal layer.
Since reporting the study, Dr. Inoue and his team have performed POEM in about 30 additional patients, and have not seen any recurrence of dysphasia. Of the treated patients, less than 10% have developed mild cases of gastroesophageal reflux disease (GERD), which has been treated with proton pump inhibitors.
The investigators reported no relevant conflicts of interest.