What is the recommended treatment approach for Per-Oral Endoscopic Myotomy (POEM) in patients with achalasia and other swallowing disorders?

Per-Oral Endoscopic Myotomy (POEM) Treatment Approach for Achalasia and Swallowing Disorders

POEM is the recommended first-line treatment for type III achalasia and should be considered as a treatment option comparable to laparoscopic Heller myotomy (LHM) for all achalasia syndromes, with specific treatment selection based on achalasia subtype. 1

Treatment Recommendations by Achalasia Subtype

Type I and Type II Achalasia

• Both pneumatic dilation (PD) and LHM are highly efficacious in randomized controlled trials; PD has less morbidity and cost 1
• POEM has shown high efficacy in short-term data compared to PD 1
• Important considerations for POEM in these subtypes:
  • Higher risk of post-procedure gastroesophageal reflux, especially with hiatal hernia 1
  • Limited long-term outcome data currently available 1
  • Insufficient data on POEM efficacy for advanced esophageal dilation, sigmoidization, epiphrenic diverticulum, and hiatal hernia 1

Type III Achalasia

• POEM is the preferred treatment option due to ability to perform longer myotomy 1
• Myotomy length should be calibrated to the spastic segment as imaged on high-resolution manometry (HRM) or thickened segment on endoscopic ultrasound (EUS) 1
• POEM is favored over LHM for this subtype specifically 2

Other Esophageal Motility Disorders

• Distal Esophageal Spasm (DES): If achalasia therapies are applied, treat as type III achalasia with POEM calibrated to the spastic segment 1
• Esophagogastric Junction (EGJ) Outflow Obstruction:
  • Many cases resolve spontaneously 1
  • Image the EGJ (EUS, CT) to rule out obstruction 1
  • If achalasia therapies are applied, consider it type II achalasia 1
• Absent Contractility deemed to be achalasia:
  • Use functional luminal imaging probe (FLIP), timed barium esophagram, or multiple repetitive swallows on HRM to establish need for treatment 1
  • If achalasia therapies are applied, consider it type I achalasia 1
• Opioid-induced dysfunction:
  • First choice: discontinue opioid
  • Second choice: botox
  • Third choice: POEM 1

Efficacy of POEM

• Clinical success rates at 1,2, and 3 years: 94%, 91%, and 90%, respectively 3
• Significant improvement in Eckardt scores from mean 7.07 pre-POEM to 1.27 post-POEM at 1 year 3
• Significant reduction in lower esophageal sphincter pressure from mean 45 mmHg to 15.6 mmHg 3
• Improvement in esophageal emptying on timed barium esophagram in 93.8% of patients at 1-year follow-up 3
• Technical success rate of 97% across large studies 3

Safety Considerations

• Major adverse events requiring medical or surgical interventions occur in approximately 14% of cases, but most can be managed conservatively 4
• Common minor adverse events include:
  • Capno/pneumoperitoneum (30.6%) 5
  • Capno/pneumothorax (11.0%) 5
  • Subcutaneous emphysema (31.6%) 5
• Serious complications are rare:
  • Mediastinal leak (0.3%) 5
  • Postoperative bleeding (1.1%) 5
  • Mortality (0.09%) 5

Post-POEM Gastroesophageal Reflux

• Post-POEM patients should be considered high risk for developing reflux esophagitis 1
• GERD documented in 28.3% of patients with 24-hour pH-impedance study 3
• Erosive esophagitis seen in 18.5% of patients post-POEM 3
• Patients should be advised about potential need for indefinite proton pump inhibitor therapy and/or surveillance endoscopy before undergoing the procedure 1

Implementation Considerations

• POEM should be performed by experienced physicians in high-volume centers 1
• An estimated 20-40 procedures are needed to achieve competence 1
• POEM should only be performed in centers able to treat potential complications such as pneumothorax or pneumoperitoneum 4
• Prior treatment for achalasia does not significantly influence the outcomes of POEM 3

Key Pitfalls and Caveats

• Accurate diagnosis is essential as several conditions can mimic achalasia (pseudoachalasia):
  • Eosinophilic esophagitis
  • Cancer
  • Reflux stricture
  • Post-myotomy stricture 1
• Patient selection should consider Chicago Classification subtype, comorbidities, disease stage, and primary or secondary causes 1
• Patients must be informed about the high risk of post-POEM reflux and the potential need for long-term PPI therapy 1
• POEM requires specialized training and should not be performed by inexperienced endoscopists 1