Function of high-resolution manometry in the analysis of peroral endoscopic myotomy for achalasia

Background: Peroral endoscopic myotomy (POEM) was introduced as a new effective therapeutic option for esophageal achalasia.

Method: A total of 112 achalasia patients categorized into three subtypes by HRM who underwent POEM were enrolled in our study. Eckardt score and HRM were performed preoperation, 6 months, and 1 year after POEM to evaluate the effectiveness, safety, and feasibility of POEM and to investigate the treatment response to POEM for the three subtypes of achalasia, classified by high-resolution manometry (HRM).

Results: POEM was successfully performed in all patients. Compared with pre-POEM scores, the Eckardt scores were significantly reduced from 7.3 ± 1.4 to 1.0 ± 0.8 6 months after POEM and to 1.2 ± 0.6 1 year after POEM (p < 0.05). The LESP before treatment was 41.8 ± 15.3 mmHg, compared with a LESP of 18.4 ± 7.1 mmHg 6 months after POEM and 20.7 ± 7.5 mmHg 1 year after POEM (p < 0.05). In addition, POEM decreased the 4-s IRP from 33.4 ± 9.0 to 14.6 ± 3.8 mmHg 6 months after POEM and to 16.4 ± 3.9 mmHg 1 year after POEM (p < 0.05). The 4-s IRP was reduced to <15 mmHg in 64 of 112 patients. Type II had the best response to POEM, while type III exhibited the worst response.

Conclusions: POEM appears to be an effective and less invasive treatment for achalasia. HRM can be useful in the classification of achalasia, while these subclassifications help to predict the responsiveness to POEM.