Salvage POEM is not index POEM

Achalasia is a chronic, incurable neurodegenerative disorder of the esophagus, of unknown etiology in most cases, characterized not only by impaired lower esophageal sphincter (LES) relaxation but also by a progressive loss of coordinated esophageal motor function and structural integrity. Clinically, it manifests with dysphagia, regurgitation with risk of aspiration pneumonia, chest pain, and weight loss, sometimes with rapid onset and progression of symptoms. Although its incidence is low [approximately 1–2 cases per 100,000 person-years (1)], reported incidence has increased approximately 4.1-fold over time, reflecting advances in diagnostic techniques.

No available therapy modifies the underlying disease process; all current interventions are palliative and aim to reduce outflow resistance at the LES to improve symptoms and esophageal emptying.

Among the interventions targeting the LES (including botulinum toxin injection, pneumatic dilation, Heller myotomy and endoscopic myotomy), those involving direct myotomy under visual control are the most effective (2).

For decades, laparoscopic Heller myotomy (HM) with partial fundoplication represented the reference standard for durable symptom control in achalasia. Its efficacy is well-established, however long-term follow-up studies have shown that up to 20–25% of patients experience persistent or recurrent symptoms after surgery (3). This lack of response or symptom recurrence may reflect incomplete disruption of the LES, or a combination of fibrosis and scarring (4), altered compliance at the esophagogastric junction, a tight fundoplication, or progression of esophageal dysfunction, including blown-out myotomy (BOM) formation (reported in up to 27% of patients after HM (5) or end-stage achalasia. More rarely, symptom recurrence may be secondary to peptic stricture formation or underlying malignancy.

Thus, recurrence after HM may sometimes be related to a technical failure, but in many cases it reflects the complex natural history of a disease that continues to evolve despite initial symptom relief. In clinical practice, it can be challenging to differentiate true disease recurrence from an initial technical failure, such as incomplete myotomy or an overly tight fundoplication.

The advent of peroral endoscopic myotomy (POEM), performed initially by Inoue in 2008 (6), transformed the therapeutic landscape of achalasia. By enabling a tailored myotomy performed from within the esophageal wall, POEM overcame several anatomical and technical constraints inherent to surgical approaches. Randomized trials demonstrated that POEM achieves efficacy comparable to Heller myotomy as first-line therapy (7), and in some phenotypes (particularly type III achalasia) it has emerged as the preferred option (2). As POEM became widespread and gained acceptance as a primary treatment, its role as a rescue strategy after failed HM became logical. POEM could offer efficacy comparable to HM while avoiding the morbidity of redo-HM [associated with postoperative complications rates of approximately 10% (8)], or pneumatic dilation, which has demonstrated inferior efficacy in a recent randomized controlled trial [62% vs. 27%, absolute difference, 35.6%; 95% confidence interval (CI): 16.4–54.7%, P=0.001] (9).

Early reports of salvage POEM published in 2013 were encouraging (10,11). Subsequent series demonstrated high technical success, a favorable safety profile, and substantial short-term symptom improvement (12).

These findings led many expert centers to adopt POEM as the default strategy for patients with recurrent symptoms after HM, typically to complete a residual distal myotomy at the level of the cardia, replacing redo surgery or repeated pneumatic dilation.

If symptom recurrence is primarily driven by incomplete surgical myotomy, should salvage POEM be expected to achieve the same long-term outcomes as index therapy?

The study by Conner and colleagues offers a timely opportunity to re-examine outcomes after POEM performed following HM, with a particular focus on long-term results (13).

The authors analyzed a cohort of 381 patients, of whom 84 underwent POEM after a failed HM (salvage POEM). In these patients, obstructive fundoplication was excluded, and there was evidence of incomplete myotomy, impaired LES relaxation on endoscopy or manometry, or a positive response to botulinum toxin. Importantly, salvage POEM was not offered to patients with sump formation and a sink-trap esophageal morphology.

By comparing salvage POEM with index POEM using propensity score matching (generating 62 matched pairs), nonlinear mixed-effects models and Rubin’s multiple imputation to project 5-year longitudinal outcomes, the authors provide a good picture of salvage POEM.

Short-term outcomes were favorable, with feasibility and safety profiles comparable to those of index POEM. These findings are consistent with early reports showing near-equivalence between salvage and index POEM (12), as well as with a meta-analysis including 9 studies and 272 patients, which showed a significant reduction in Eckardt score (mean decrease 5.14; 95% CI: 4.19–6.09) and a pooled clinical success (defined as Eckardt Score ≤3 post POEM) rate of 90.0% (95% CI: 83.1–96.8%) across six studies, albeit with significant heterogeneity (12).

These results suggest that prior surgical scarring does not preclude favorable outcomes in expert centers; however, technical challenges may arise that are particularly demanding for less-experienced operators. For instance, in the presence of BOM, septotomy of the pseudodiverticular septum (analogous to a Z-POEM technique) may be required.

Regarding long-term outcomes, Conner and colleagues estimated that at 5 years, clinical success after salvage POEM was significantly lower than after index POEM (67% vs. 80%, P=0.028). These findings are consistent with a previous multicenter retrospective study reporting lower clinical response rates in patients with prior HM compared with treatment-naïve patients [81% vs. 94% (14)], likely reflecting more advanced disease at the time of salvage intervention.

Timed barium esophagram demonstrated that complete esophageal emptying remained suboptimal in both groups during long-term follow-up, with a trend toward less frequent complete emptying after salvage POEM.

It should also be noted that Conner and colleagues excluded patients with advanced esophageal sink-trap morphology, a subgroup in whom clinical response to salvage POEM be expected to be even less favorable.

This observation underscores an essential point: symptom recurrence after myotomy may not be solely a sphincter-related problem. In many patients, esophageal body dysfunction, elongation, sump formation with sink-trap morphology, or angulation at the hiatus likely contribute to impaired clearance, thereby limiting the benefit achievable by further reduction of junctional resistance.

In clinical practice, many patients who fail to respond to salvage POEM present with advanced disease, including BOM, sump formation, or end-stage achalasia, conditions that may ultimately require esophagectomy or, alternatively, other less aggressive palliative treatments. In this study, there was a nonsignificant trend toward higher incidence of secondary interventions in the post-HM group (7 of 62 patients after salvage POEM vs. 4 of 62 after index POEM). The authors primarily employed pneumatic balloon dilation as a secondary intervention, reserving esophagectomy for patients experiencing recurrent aspiration pneumonia, failure to thrive, or markedly impaired quality of life.

Another clinically relevant observation concerns gastroesophageal reflux disease (GERD). The authors did not find statistically significant differences in abnormal acid exposure or in the presence of esophagitis between salvage POEM and index POEM, suggesting that prior fundoplication does not confer a protective effect in the setting of salvage myotomy. These results are consistent with a previous study reporting no significant differences in GERD outcomes between salvage and index POEM (14). Together, these findings suggest that partial fundoplication may not protect against reflux after salvage POEM, a procedure that extends a previous myotomy, and may therefore be associated with an increased risk of GERD (15). Supporting this interpretation, a higher incidence of postoperative GERD has been reported after redo HM compared to index HM (8).

Accordingly, the presence of a prior fundoplication should not preclude systematic reflux surveillance or appropriate management in these patients.

Despite its retrospective nature, and inherent limitations, the study methodology includes the use of propensity score matching and the incorporation of esophageal morphology (including the length-to-height ratio) into the adjustment strategy.

These study observations carry important implications for clinical practice. Salvage POEM should remain a central component of the therapeutic armamentarium for achalasia after failed HM. It is less invasive than redo surgery, adaptable to complex anatomy, and associated with meaningful symptom relief in most patients. However, patient counseling must be realistic. Salvage POEM (like all achalasia interventions) offers palliation rather than restoration. Long-term symptom control is achievable, but the likelihood of recurrence and the need for additional interventions are higher than after index POEM.

Follow-up strategies should reflect this reality. Patients undergoing salvage POEM may benefit from closer long-term surveillance, incorporating not only symptom assessment but also objective evaluation of esophageal emptying and reflux, as suggested by the authors.

Several questions remain unanswered. The relative contribution of fibrosis, altered junctional compliance, and esophageal body dysfunction (including BOM and sump formation with a sink-trap esophageal morphology) to salvage failure remains poorly defined. The role of newer tools, such as Functional Lumen Imaging Probe (16), in selecting candidates for salvage POEM or in guiding the extent and completion of myotomy warrants further investigation, particularly with respect to predicting long-term outcomes.

In the meantime, it is important to recognize that achalasia is a chronic, noncurable disease. Even the most effective treatment options, including POEM and salvage POEM, primarily target the LES, and in advanced or complex disease this may be insufficient to fully improve symptoms or restore quality of life.

Acknowledgments

None.

Footnote

Provenance and Peer Review: This article was commissioned by the editorial office, Annals of Laparoscopic and Endoscopic Surgery. The article has undergone external peer review.

Peer Review File: Available at https://ales.amegroups.com/article/view/10.21037/ales-2026-1-0007/prf

Funding: None.

Conflicts of Interest: The author has completed the ICMJE uniform disclosure form (available at https://ales.amegroups.com/article/view/10.21037/ales-2026-1-0007/coif). H.U. reports proctor roles in ERBE Spain, Olympus Iberia, and Boston scientific. The author has no other conflicts of interest to declare.

Ethical Statement: The author is accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

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References

1. Lee K, Hong SP, Yoo IK, et al. Global trends in incidence and prevalence of achalasia, 1925-2021: A systematic review and meta-analysis. United European Gastroenterol J 2024;12:504-15. [Crossref] [PubMed]
2. Vaezi MF, Pandolfino JE, Yadlapati RH, Greer KB, Kavitt RT. ACG Clinical Guidelines: Diagnosis and Management of Achalasia. Am J Gastroenterol 2020;115:1393-411. [Crossref] [PubMed]
3. Barron JO, Toth AJ, Blackstone EH, Ramji S, Jain N, Tasnim S, Thota PN, Gabbard SL, Zanoni A, Sudarshan M, Murthy SC, Raja S. Heller myotomy for esophageal achalasia: Outcomes in 1010 patients with longitudinal follow-up. J Thorac Cardiovasc Surg 2025;170:1821-1830.e4. [Crossref] [PubMed]
4. Shiwaku H, Inoue H, Nimura S, et al. Histological findings of divided muscle after peroral endoscopic myotomy. Ann Gastroenterol 2016;29:94-5.
5. Triggs JR, Krause AJ, Carlson DA, et al. Blown-out myotomy: an adverse event of laparoscopic Heller myotomy and peroral endoscopic myotomy for achalasia. Gastrointest Endosc 2021;93:861-8.e1.
6. Inoue H, Minami H, Kobayashi Y, et al. Peroral endoscopic myotomy (POEM) for esophageal achalasia. Endoscopy 2010;42:265-71. [Crossref] [PubMed]
7. Werner YB, Hakanson B, Martinek J, et al. Endoscopic or Surgical Myotomy in Patients with Idiopathic Achalasia. N Engl J Med 2019;381:2219-29. [Crossref] [PubMed]
8. Capovilla G, Salvador R, Provenzano L, et al. Laparoscopic Revisional Surgery After Failed Heller Myotomy for Esophageal Achalasia: Long-Term Outcome at a Single Tertiary Center. J Gastrointest Surg 2021;25:2208-17. [Crossref] [PubMed]
9. Saleh CMG, Familiari P, Bastiaansen BAJ, et al. The Efficacy of Peroral Endoscopic Myotomy vs Pneumatic Dilation as Treatment for Patients With Achalasia Suffering From Persistent or Recurrent Symptoms After Laparoscopic Heller Myotomy: A Randomized Clinical Trial. Gastroenterology 2023;164:1108-1118.e3. [Crossref] [PubMed]
10. Onimaru M, Inoue H, Ikeda H, et al. Peroral endoscopic myotomy is a viable option for failed surgical esophagocardiomyotomy instead of redo surgical Heller myotomy: a single center prospective study. J Am Coll Surg 2013;217:598-605. [Crossref] [PubMed]
11. Zhou PH, Li QL, Yao LQ, et al. Peroral endoscopic remyotomy for failed Heller myotomy: a prospective single-center study. Endoscopy 2013;45:161-6. [Crossref] [PubMed]
12. Huang Z, Cui Y, Li Y, et al. Peroral endoscopic myotomy for patients with achalasia with previous Heller myotomy: a systematic review and meta-analysis. Gastrointestinal Endoscopy 2021;93:47-56.e5.
13. Conner A, Jain N, Barron JO, et al. When the gold standard fails: Propensity-matched comparison of peroral endoscopic myotomy after Heller myotomy versus index peroral endoscopic myotomy. J Thorac Cardiovasc Surg 2026;171:519-529.e9. [Crossref] [PubMed]
14. Ngamruengphong S, Inoue H, Ujiki MB, et al. Efficacy and Safety of Peroral Endoscopic Myotomy for Treatment of Achalasia After Failed Heller Myotomy. Clinical Gastroenterology and Hepatology 2017;15:1531-1537.e3.
15. Wu Y, Grieme A, Garza M, et al. Impact of myotomy length on per-oral endoscopic myotomy (POEM) outcomes for achalasia: a meta-analysis of randomized trials. Surg Endosc 2025;39:7428-37. [Crossref] [PubMed]
16. Nguyen AD, Carlson DA, Patel A, et al. AGA Clinical Practice Update on Incorporating Functional Lumen Imaging Probe Into Esophageal Clinical Practice: Expert Review. Gastroenterology 2025;169:726-736.e1. [Crossref] [PubMed]