Incomplete upper esophageal sphincter relaxation: association with achalasia but not other esophageal motility disorders.

Incomplete upper esophageal sphincter (UES) relaxation is not well understood. We compared clinical and manometric characteristics of patients with normal and abnormal UES relaxation. Consecutive patients (n = 208) underwent manometric evaluation of the lower esophageal sphincter (LES), esophageal body, and UES/pharynx. The patients were divided into those with abnormal UES relaxation (residual pressure > 6.7 mmHg) (n = 21) and normal relaxation (n = 187). Clinical and manometric profiles were compared. Sex, age, and presenting complaint did not correlate with UES relaxation. Normal esophageal peristaltic sequences were more frequently present in the normal UES group (73.6%) compared with the abnormal (55.8%) (p < 0.01). The UES relaxation was shorter in the group with abnormal relaxation (410.0 ms vs. 510.2 ms, p < 0.001). All other manometric parameters were not different between the two groups. When individual manometric diagnoses were analyzed, only achalasia was noted to be more common in the abnormal UES group (23.8% vs. 9.1%, p < 0.05), and a trend was noted toward diffuse esophageal spasm being more common (14.3% vs. 9.6%, not significant). We conclude that incomplete UES relaxation is a rare manometric finding, associated with achalasia and not specifically associated with any other motility disturbance. This finding may represent a secondary response to the poor esophageal emptying seen in achalasia.