Peroral endoscopic myotomy (POEM) has proven to be highly effective in the treatment of achalasia and has shown promising outcomes for other esophageal motility disorders. A growing body of literature supports POEM procedures as a safe and effective therapy for the management of achalasia.
“POEM is a minimally invasive alternative to traditional surgery for patients not responding to conventional endoscopic and medical therapies,” said Julianna Yang, M.D., assistant professor of gastroenterology at Vanderbilt University Medical Center. “Not all centers offer POEM because it requires a multidisciplinary approach, specialized advanced endoscopic training and a high degree of technical precision.”
Yang, an expert in the POEM procedures for achalasia and spastic esophageal disorders, has also led international studies of its application in the management of esophageal diverticula (D-POEM) and Zenker’s diverticulum (Z-POEM). She recently joined the faculty at the Vanderbilt Digestive Disease Center to help build a clinical and research program around the technique.
POEM Procedures for Achalasia
Achalasia is a rare esophageal motility disorder characterized by loss of peristalsis and failed relaxation of the lower esophageal sphincter (LES). This results in a wide array of symptoms including dysphagia, regurgitation, chest pain, aspiration and weight loss. Standard treatments include pneumatic balloon dilation, botulinum toxin injection or dividing the LES surgically using techniques such as open or laparoscopic Heller myotomy (LHM) or pneumatic endoscopic dilation.
POEM was first introduced in 2007 in a porcine model and brought into clinical practice in 2010. The POEM technique utilizes a high-definition endoscope and endoscopic knife that allows for the creation of a submucosal tunnel; within this tunnel, myotomy is performed. POEM procedures must be performed under general anesthesia with endotracheal intubation. “Post-POEM, a patient will typically remain in the hospital 24 hours for observation,” Yang said.
Over the past nine years, POEM has shown a favorable safety and efficacy profile, with most adverse effects mild to moderate; less than one percent were severe. Studies have shown a 98 percent average clinical success rate with a mean follow-up of 12 months following POEM. This is comparable with the efficacy of LHM.
POEM has several advantages compared to surgical interventions. First, it is less invasive, as surgery often requires thoracotomy or thoracoscopy to reach the esophagus. LHM is limited by the length of the esophagus that can be reached. POEM allows full visualization of the entire esophagus and omits the need for thoracotomy or thoracoscopy.
POEM for Rescue and Difficult Cases
Although LHM is safe and effective in the management of achalasia, persistent or recurrent symptoms can occur in 3.5 to 15 percent of cases. This has been attributed to inadequate myotomy, which is circumvented in POEM with complete myotomy via direct endoscopic visualization. In the subset of patients with recurrent symptoms, POEM has been shown to have promising short-term outcomes after prior failed LHM, with a success rate between 92 to 100 percent.
Another advantage is that POEM can be performed safely in geriatric and pediatric patients. In elderly patients with significant comorbidities, POEM offers a minimally invasive alternative to surgical interventions. Although achalasia is a rare disease in children, studies have shown that POEM can be performed successfully in infants as young as 11 months.
The most challenging long-term complication of POEM is gastroesophageal reflux disease (GERD), with reported rates between six and 88 percent. “This wide variation can be due to variability in access and measurement of GERD,” Yang said. “Post-POEM, we initially prescribe acid suppression medication for all patients. This is subsequently individualized to each patient’s symptoms.”
POEM for Other Esophageal Motility Disorders
As POEM has gained a wider acceptance for treating achalasia, it has been expanded to other complex esophageal motility disorders. These include distal esophageal spasms, jackhammer esophagus and esophagogastric junction outflow obstruction. Yang said that POEM is a promising treatment for these conditions because it allows for long myotomy into the esophageal body where the spasm may be occurring.