Type II achalasia is associated with a comparably favorable outcome following per oral endoscopic myotomy

Factors associated with peroral endoscopic myotomy for achalasia outcomes: systematic review and meta-analysis

BACKGROUND

Peroral endoscopic myotomy (POEM) is an emerging effective treatment for achalasia. However, a significant proportion of patients do not respond well to the treatment. After over a decade of clinical practice, potential risk factors associated with POEM failure have been identified. This meta-analysis aimed to summarize the evidence of risk factors for POEM failure.

METHODS

A systematic literature search was conducted on PubMed, Embase, Web of Science, and Cochrane Library from inception to June 10th, 2022. We included English studies that reported POEM outcomes in achalasia patients and identified risk factors for POEM failure. Relevant information was extracted and analyzed using fixed- or randomized-effect models to pool the effect size.

RESULTS

A total of 27 studies comprising 9371 patients with achalasia were included in this review. The pooled failure rate was 8% (90% CI 7%-10%). We identified sigmoid esophagus (OR 1.90, 95% CI 1.45-2.47), type I achalasia (OR 1.30, 95% CI 1.04-1.63), and type III achalasia (OR 1.26, 95% CI 0.89-1.78) were associated with a worse clinical response. Conversely, type II achalasia was associated with a better response (OR 0.59, 95% CI 0.47-0.75). Prior treatment with Heller myotomy (OR 5.75, 95% CI 3.97-8.34) and prior balloon dilation (OR 1.18, 95% CI 1.07-1.29) were also associated with a higher risk of clinical failure.

CONCLUSION

Our meta-analysis results demonstrated that sigmoid esophagus, manometric achalasia subtype, and prior treatment were associated with POEM failure. This information could be used to guide treatment decisions and improve the success rate of POEM in achalasia patients.

[Therapy of esophageal motility disorders]

Esophageal motility disorders are diseases in which there are malfunctions of the act of swallowing due to a change in neuromuscular structures. The main symptom is therefore dysphagia for solid and/or liquid foods, often accompanied by symptoms such as chest pain, regurgitation, heartburn, and weight loss. Esophageal manometry is the gold standard in diagnostics. Endoscopy and radiology serve to exclude inflammatory or malignant changes. With the introduction of high-resolution esophageal manometry (HRM), the diagnosis of esophageal motility disorders has improved and led to a new classification with the Chicago Classification, which has been modified several times in the last decade, most recently in 2020 with the Chicago Classification v4.0. Compared to the previous version 3.0, there are some important changes that are presented based on the most important esophageal motility disorders in everyday clinical practice.

[Therapy of esophageal motility disorders]

Esophageal motility disorders are diseases in which there are malfunctions of the act of swallowing due to a change in neuromuscular structures. The main symptom is therefore dysphagia for solid and/or liquid foods, often accompanied by symptoms such as chest pain, regurgitation, heartburn, and weight loss. Esophageal manometry is the gold standard in diagnostics. Endoscopy and radiology serve to exclude inflammatory or malignant changes. With the introduction of high-resolution esophageal manometry (HRM), the diagnosis of esophageal motility disorders has improved and led to a new classification with the Chicago Classification, which has been modified several times in the last decade, most recently in 2020 with the Chicago Classification v4.0. Compared to the previous version 3.0, there are some important changes that are presented based on the most important esophageal motility disorders in everyday clinical practice.

Long-term outcomes of peroral endoscopic myotomy for Chicago classification type I vs type III achalasia in treatment-naive patients

The efficacy of peroral endoscopic myotomy (POEM) for achalasia has potential associations with Chicago classification by high-resolution manometry (HRM). Type II achalasia demonstrates the best response to POEM of all subtypes, while there remain controversies between type I and type III. Moreover, previous treatment history might cause discrepancy in direct comparison. We aimed to compare the clinical outcome of POEM for type I vs type III in treatment-naive patients. In total, 82 patients with type I or type III achalasia (45 type I, 37 type III) from February 2015 to December 2018 were enrolled and POEM was carried out as the initial treatment. Clinical success, change of Eckardt scores and HRM parameters were analyzed and compared between type I and type III group. About, 43 (95.6%) patients and 34 (91.9%) patients in type I and type III group acquired the clinical success (P = 0.821). Eckardt score and HRM results after POEM treatment decreased significantly in either group (P<0.01). Compared to type III group, higher reduction rates of Eckardt score (type I vs type III, 78.6 vs 66.9%, P = 0.034) and basal LES pressure (type I vs type III, 58.9 vs 40.4%, P = 0.040) were observed in type I group. Type I achalasia patients showed better response to POEM with more favorable clinical remission in Eckardt score and HRM outcomes than type III.

Modified Peroral Endoscopic Myotomy Technique for Type II Achalasia: A Multicenter Retrospective Study

Aim

This retrospective study is aimed at evaluating the outcomes of a modified peroral endoscopic myotomy (POEM) technique in patients with type II achalasia.

Methods

We performed a modified POEM procedure, which involved a shorter (total myotomy length = 4 cm), full-thickness myotomy, on 31 patients with type II achalasia. Clinical success rates, technical success rates, pre- and postoperative esophageal manometry results, complications, and reflux-related adverse events were evaluated.

Results

The clinical success (Eckardt score ≤ 3) rates were 100% and 88.9% within 2 years and beyond 2 years postoperatively, respectively. The median lower esophageal sphincter pressures (LESP) decreased from 31.6 (26.7-49.7) mmHg preoperatively to 13.4 (10.5-21.6) and 11.8 (7.4-16.7) mmHg (P < 0.001) at 6 and 12 months postoperatively, respectively. The median integrated relaxation pressure (IRP) decreased from 27.8 (20.6-37.5) mmHg preoperatively to 12.9 (11.3-23.4) and 11.6 (9.6-16.8) mmHg (P < 0.001) at 6 and 12 months after POEM, respectively. Only one case (3.2%) of mucosal injury, four (12.9%) cases of reflux esophagitis, and two (6.5%) cases of gastroesophageal reflux symptoms were reported.

Conclusions

The modified POEM technique showed excellent outcomes in patients with type II achalasia.