The efficacy of peroral endoscopic myotomy (POEM) for type III achalasia: a systematic review and meta-analysis

Peroral endoscopic myotomy (POEM), a newly invented treatment for patients with achalasia, has achieved great success; however, for the rarest manometric subtype (type III), its efficacy remains unknown. We aimed to evaluate the efficacy of peroral endoscopic myotomy (POEM) for type III achalasia.

A search was conducted in three databases (PubMed, Embase, and Cochrane Library) from inception to July 2025. The primary outcome was the pooled efficacy (defined by an Eckardt score ≤ 3 after the operation) at the longest available follow-up time. Secondary outcomes included the assessment of clinical efficacy over time, the impact of myotomy length on efficacy, and the evaluation of postoperative reflux.

Twenty studies involving 606 patients with type III achalasia were included. The pooled efficacy of POEM for type III achalasia was 89.3% (95% CI: 85-93%), with moderate heterogeneity (I² = 38.1%). Subgroup analyses revealed that heterogeneity was attributed to a single influential study. Subgroup analyses based on patient age, sex, and myotomy length revealed no statistically significant differences in efficacy. A significant decrease in efficacy was observed between the early (3-6 months: 93.6%) (95% CI: 85.7-98.9%) and long-term (24 months: 78.5%) (95% CI: 64.3-90.2%) follow-up groups (p = 0.027). In this study, postoperative reflux incidence varied widely due to the lack of standardized assessment methods.

This meta-analysis on POEM for type III achalasia showed a pooled success rate of 89.3%, with efficacy declining significantly from early (3-6 months) to long-term (24 months) follow-up. Myotomy length did not influence outcomes. Postprocedural GERD incidence assessed by symptoms, endoscopy, and pH monitoring were 18.7, 25.6, and 60.8%, supporting empirical PPI use and combined objective surveillance. Given the retrospective, small-sample evidence, POEM is effective in experienced centers but not yet a universal recommendation; randomized trials versus LHM with fundoplication are needed to establish it as first-line therapy.