Discordance between high-resolution manometry, esophagoscopy and contrast esophagogram in determining landmarks for per-oral endoscopic myotomy in spastic esophageal disorders: a word of caution.

BACKGROUND: Myotomy length for per-oral endoscopic myotomy (POEM) is standardized for type I and II achalasia. However, for type III achalasia, jackhammer esophagus, diffuse esophageal spasms and esophagogastric junction outflow obstruction, there is no standard. Determining myotomy length based on the high-pressure zone found during high-resolution manometry (HRM) and spastic length found during esophagography may be used to determine adequate myotomy length without excess muscle destruction. METHODS: The records of patients who have undergone POEM procedures at our institution had the following data gleaned: age, sex, esophageal spastic diagnosis, length of high-pressure zone and lower esophageal sphincter (LES) position by HRM, length of spastic esophagus by esophagography, position of the z-line by esophagoscopy and length of myotomy performed. Outcomes were assessed based on patient symptomatic improvement and need for re-intervention. RESULTS: 71 patients were evaluated for POEM, with 67 completing POEM. There was an average difference in LES position by HRM and z-line position by esophagoscopy of 3.9 ± 3.0 cm. There was an average difference in high-pressure zone by HRM and spastic length by esophagography of 4.9 ± 3.2 cm. Overall, with a median of 20 months follow-up, 74% achieved long-term symptomatic improvement, with 17 patients requiring re-intervention. CONCLUSIONS: Discordance among HRM, esophagography and esophagoscopy can be significant. Caution should be employed with using these methods to determine myotomy length in POEM.