Experts Recommend Key Modifications to High-Resolution Manometry

David A. Johnson, MD


April 13, 2021

The field of esophagology was transformed by the pioneering work of the late Dr Ray Clouse, who developed color topographic plots to more accurately assess esophageal motility. Clouse's spirit of innovation in this area has since been taken up by the International High-Resolution Manometry (HRM) Working Group, who released their first version of the Chicago Classification (CC) system in 2009. The goal of the initial classification system, and subsequent versions released thereafter, was to apply rigorous methodology to unify and clarify not only the diagnosis of esophageal motility disorders but also the clinical implications, as defined by HRM.

The Working Group has now released their most-recent update — CCv4.0 — which drew upon the work of 52 esophageal experts from five continents and 20 countries. The consensus group recognized that many of the previous CC diagnoses represented incidental findings and did not imply the need for interventive therapy. Accordingly, the latest modifications featured in CCv4.0 reflect diagnostic patterns of unequivocal, vs unclear, clinical relevance.

The updated classification system includes several key changes which are helpfully summarized in an accompanying review paper.

What's New in CCv4.0

The authors recommend that the diagnostic approach be bifurcated into disorders of esophagogastric junction outflow obstruction (EGJOO) and disorders of peristalsis.

They also set forth a new standardized HRM protocol. The previous standard called for 10 wet swallows in the supine position. However, more recent evidence indicates that this may be insufficient for obtaining a definitive diagnosis to guide therapy. The modified protocol in CCv4.0 now recommends including wet swallows in both supine and upright positions, as well as multiple swallows in the supine position and a "rapid drink test" in the upright position. These extended swallows are not to be done if there is obvious achalasia with an increased risk for aspiration.

The diagnostic patterns for achalasia — elevated lower esophageal sphincter (LES) integrated relaxation pressure (IRP) and 100% absent peristalsis (defined as all swallows failed or premature) — remain unchanged. There is a caveat, however, that opioid-induced esophageal dysfunction (notably for type III achalasia) is distinct from primary achalasia. Therapeutic interventions should be appropriately conservative in these cases.

The diagnostic pattern for absent contractility (normal IRP and 100% failed peristalsis) is unchanged, although this should be done in both supine and upright positions.

The diagnosis of EGJOO has been characterized previously by elevated esophageal IRP but intact peristalsis. It is now evident that a substantial number of EGJOO cases in the supine position alone are unrelated to LES dysfunction. The new criteria call for elevated IRP in both supine and upright positions. Furthermore, the diagnosis should be considered as inconclusive in the absence of clinical symptoms of dysphagia or noncardiac chest pain. Supportive testing with anatomic assessment by timed barium swallow or functional luminal imaging probe is recommended to confirm the diagnosis. In the absence of adjunctive testing and clinical symptoms, the authors advise taking a cautious approach to EGJOO.

Disorders of peristalsis include absent contractility, diffuse esophageal spasm, hypercontractile esophagus, and ineffective esophageal motility.

Again, the authors note that opioids can lead to a pattern of distal esophageal spasm.

The diagnosis of ineffective esophageal motility has changed to require > 70% of swallows as ineffective. This diagnosis now encompasses diagnoses of fragmented peristalsis, which was previously defined as fragmented peristalsis with > 50% of swallows with a break (> 5 cm) and not otherwise matching criteria for ineffective esophageal motility by previous CCv3.0 criteria.

Overall, these updated guidelines are meant to better characterize and direct the appropriate therapeutic management for patients with esophageal motility disorders. They are a must-read for clinicians who evaluate these patients, and particularly for those who interpret the HRM reports.

David A. Johnson, MD, a regular contributor to Medscape, is professor of medicine and chief of gastroenterology at Eastern Virginia Medical School in Norfolk, Virginia, and a past president of the American College of Gastroenterology. His primary focus is the clinical practice of gastroenterology. He has published extensively in the internal medicine/gastroenterology literature, with principal research interests in esophageal and colon disease, and more recently in sleep and microbiome effects on gastrointestinal health and disease.

Follow Medscape on Facebook, Twitter, Instagram, and YouTube


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.