Is peroral endoscopic myotomy (POEM) helpful for Type 1 achalasia?

POEM for Type 1 Achalasia: Efficacy and Considerations

For Type 1 achalasia, peroral endoscopic myotomy (POEM) is highly efficacious with symptom improvement rates of 89-97%, but pneumatic dilation (PD) and laparoscopic Heller myotomy (LHM) remain first-line treatments with less morbidity and cost. 1

Treatment Options for Type 1 Achalasia

• According to the American Gastroenterological Association (AGA) guidelines, both pneumatic dilation (PD) and laparoscopic Heller myotomy (LHM) are highly efficacious first-line treatments for Type 1 achalasia, with PD having less morbidity and cost 1, 2
• POEM has demonstrated high efficacy in randomized controlled trials compared to PD for Type 1 achalasia, but only short-term data is available 1
• Clinical success rates for POEM across all achalasia types range from 89-97% in large uncontrolled trials with follow-up periods of 11-36 months 1

Efficacy of POEM for Type 1 Achalasia

• POEM significantly reduces Eckardt symptom scores from pre-procedure means of 6.8 to post-procedure means of 1.2, indicating substantial symptom improvement 3
• Objective measurements show POEM reduces lower esophageal sphincter pressure by approximately 66% and improves timed barium esophagram column height by 80% 3
• In multicenter studies, 97% of patients achieved symptom remission at 3 months post-POEM, with 82% maintaining remission at 12 months 4

Important Considerations and Limitations

• Post-POEM gastroesophageal reflux is a significant concern, with studies showing esophagitis in up to 19-33% of patients and abnormal pH studies in 47.8% of patients 1, 3
• Patients should be advised about the potential need for indefinite proton pump inhibitor therapy and/or surveillance endoscopy before undergoing POEM 1, 2
• There is insufficient data on the efficacy of POEM for advanced esophageal dilation, sigmoidization, epiphrenic diverticulum, and hiatal hernia in Type 1 achalasia 1

Predictive Factors for POEM Outcomes

• Advanced achalasia stage and long symptom duration are independent predictive factors for poor treatment outcomes after POEM 5
• Post-POEM esophageal diameter >3 cm is associated with treatment failure as assessed by Eckardt score and timed barium esophagram 5

Procedural Considerations

• POEM should be performed by experienced physicians in high-volume centers, with an estimated 20-40 procedures needed to achieve competence 2
• Minor adverse events include capno/pneumoperitoneum (30.6%), capno/pneumothorax (11.0%), and subcutaneous emphysema (31.6%), while major adverse events are rare (mediastinal leak 0.3%, bleeding 1.1%) 3

Treatment Algorithm for Type 1 Achalasia

1. For initial treatment of uncomplicated Type 1 achalasia: Consider PD or LHM as first-line options due to established long-term efficacy and lower costs 1
2. Consider POEM as an alternative first-line treatment when:
   • Expertise is available at a high-volume center 2
   • Patient understands and accepts the higher risk of post-procedure reflux 1, 2
3. POEM may be particularly valuable for Type 1 achalasia patients with:
   • Previous failed Heller myotomy (90% success rate in this population) 6
   • Need for retreatment after PD 2

In conclusion, while POEM is effective for Type 1 achalasia with high success rates, the AGA guidelines still recommend PD or LHM as preferred initial treatments due to their established long-term efficacy, lower costs, and lower reflux rates. POEM remains an excellent option when performed by experienced endoscopists, particularly in cases of previous treatment failure.