Records from 910 patients referred to our clinical esophageal manometry laboratory for evaluation of noncardiac chest pain between January 1983 and December 1985 were reviewed and compared with records from 251 patients referred for dysphagia. Evaluation included baseline esophageal manometry, acid perfusion test, and edrophonium provocation. In the chest-pain group, 655 patients (72%) had normal esophageal motility and 255 (28%) had abnormal motility. Nutcracker esophagus was present in 48% of abnormal tracings, suggesting that it is a manometric marker for noncardiac chest pain. Of the total chest-pain group, 243 patients (27%) had their pain reproduced during provocative testing ("definite" esophageal pain); 192 patients (21%) had baseline manometric abnormalities but no pain during provocative testing ("probable" esophageal chest pain). The highest percentage of positive provocative responses (34%) occurred in patients with nutcracker esophagus on baseline manometry. Manometric abnormalities were statistically commoner (p less than 0.001) in patients with dysphagia, occurring in 53%. Achalasia (36%) and nonspecific esophageal motility disorders (38%) were the commonest abnormalities in this group, with nutcracker esophagus being infrequent (10%).

Distal esophageal contractile amplitude and duration after wet swallows increases with age. Triple-peaked waves and wet-swallow-induced simultaneous contractions should suggest an esophageal motility disorder. Double-peaked waves are a common variant of normal. Dry swallows have little use in the current evaluation of esophageal peristalsis.

If 24-hour esophageal pH monitoring is to be a useful diagnostic tool, it must reliably discriminate gastroesophageal reflux patients despite daily variations in distal esophageal acid exposure. To address this issue, we studied 53 subjects (14 healthy normals, 14 esophagitis patients, and 25 patients with atypical symptoms) with two ambulatory pH tests performed within 10 days of each other. Intrasubject reproducibility of 12 pH parameters to discriminate the presence of abnormal acid reflux was determined. As a group, the parameters of percent time with pH less than 4 (total, upright, recumbent) were most reproducible (80%). Therefore, a subject was defined as having gastroesophageal reflux disease if at least one of these three values were abnormal. Intrasubject reproducibility for the diagnosis of reflux disease was 89% for the entire sample. Among subsets, the reproducibility was 93% for the normals and esophagitis patients and 84% for the atypical symptom patients. Total percent time with pH less than 4 was the single most discriminate pH parameter (85%) and nearly equaled that of the three combined parameters (89%). The intrasubject variability of this parameter was determined by the mean +/- 2 SD of the relative differences between the two test results for all 53 subjects. Total percent time with pH less than 4 may vary between tests by a factor of 3.2-fold or less (218% higher to 69% lower). We conclude: (1) ambulatory 24-hr esophageal monitoring is a reproducible test for the diagnosis of gastroesophageal reflux disease; and (2) the large intrastudy variability in 24-hr total acid exposure may limit this test's usefulness as a measurement of therapeutic improvement.