Reproducibility of esophageal high‐resolution manometry

Background Esophageal high‐resolution manometry (HRM) is a novel method for esophageal function testing that has prompted the development of new parameters for quantitative analysis of esophageal function. Until now, the reproducibility of these parameters has not been investigated. Methods Twenty healthy volunteers underwent HRM on two separate days. Standard HRM parameters were measured. In addition, in conventional (virtual) line tracings, lower esophageal sphincter (LES) resting pressure, relaxation pressure, and relative relaxation pressure were measured. Firstly, for each variable, the mean percentage of covariation (100 × SD/mean: %COV) was derived as a measure of inter‐ and intra‐individual variation. Secondly, Kendall’s coefficients of concordance (W values) were calculated. Thirdly, Bland–Altman plots were used to express concordance graphically. Key Results Statistically significant concordance values were found for upper esophageal sphincter (UES) pressure (W = 0.90, P = 0.02), transition zone length (W = 0.92, P = 0.01), LES length (W = 0.81, P = 0.04), LES pressure (W = 0.75, P = 0.05), LES relaxation pressure (W = 0.75, P = 0.03), relative LES relaxation pressure (W = 0.78, P = 0.05), gastric pressure (W = 0.81, P = 0.04), and contraction amplitude 5 cm above the LES (W = 0.86, P = 0.03). In conventional setting, only LES resting pressure (W = 0.835, P = 0.03) proved significant. In HRM tracings, concordance values for contraction wave parameters, and in conventional line tracings, LES relaxation pressure and relative relaxation pressure did not reach levels of statistical significance. Conclusions & Inferences Esophageal HRM yields reproducible results. Parameters that represent anatomic structures show better reproducibility than contraction wave parameters. The reproducibility of LES resting and relaxation pressure assessed with HRM is better than with conventional manometry and further supports the clinical use of HRM.     

Alexithymia and anxiety sensitivity in patients with non-cardiac chest pain

The aim of this study was to examine independent and combined influences of alexithymia and anxiety sensitivity on chest pain and life interference in patients with non-cardiac chest pain (NCCP). Theories of NCCP posit a central role for emotion in the experience of chest pain, however, studies have not examined how alexithymia characterized by a difficulty identifying or verbalizing emotions, may influence this relationship. This study examined 231 patients (56% females, M age = 50 years) with chest pain seeking cardiac evaluation, who showed no abnormalities during exercise tolerance testing. Forty percent (40%) scored at or above the moderate range of alexithymia. Whereas health care utilization was associated with elevated alexithymia among men, health care utilization was associated with elevated anxiety sensitivity among women. Hierarchical regression analyses revealed that alexithymia and anxiety sensitivity were both uniquely and independently associated with pain severity and life interference due to pain. Alexithymia-pain links were stronger for men compared to women. Secondary analyses conducted with a subsample suggest that alexithymia may be increasingly stable over time (i.e., 18-month follow-up). Findings are largely congruent with theoretical models of NCCP showing that personality and emotional factors are important in this medically unexplained syndrome.     

Multiple rapid swallow responses segregate achalasia subtypes on high‐resolution manometry

Background Multiple rapid swallows (MRS) inhibit esophageal peristalsis and lower esophageal sphincter (LES) tone; a rebound excitatory response then results in an exaggerated peristaltic sequence. Multiple rapid swallows responses are dependent on intact inhibitory and excitatory neural function and could vary by subtype in achalasia spectrum disorders. Methods Consecutive subjects with incomplete LES relaxation on high‐resolution manometry (HRM) (Sierra Scientific, Los Angeles, CA, USA) in the absence of mechanical obstruction were prospectively identified. Achalasia spectrum disorders were classified and HRM plots reviewed according to Chicago criteria. Esophageal peristaltic performance and LES function were assessed after 10 wet swallows and MRS (five 2 mL water swallows 2–3 s apart). Findings were compared with 18 healthy controls (28.5 ± 0.6 years, 44% women). Key Results A total of 46 subjects (57.1 ± 2.1 years, 52.2% women) met inclusion criteria. There was complete failure of peristalsis with MRS in all subjects with achalasia subtypes 1 and 2. In contrast, 80% of achalasia subtype 3 and incomplete LES relaxation (EGJ outflow obstruction) with preserved esophageal body peristalsis had a contractile response to MRS (P < 0.001 compared with subtypes 1 and 2); controls demonstrated 94.4% peristalsis. Percent decrease in LES residual pressure during MRS (compared to wet swallows) segregated achalasia subtypes; those with aperistalsis (subtypes 1 and 2) had a lesser decline (22.6%) compared to those with retained esophageal body peristalsis (40.5%) and controls (51.3%, P < 0.001 across groups). Conclusions & Inferences Multiple rapid swallow responses segregate achalasia spectrum disorders into two patterns differentiated by presence or absence of esophageal body contraction response to wet swallows. These findings support subtyping of achalasia, with pathophysiologic implications.     

Optimizing the swallow protocol of clinical high‐resolution esophageal manometry studies

Background The Chicago Classification (CC) of Esophageal Motility Disorders is based on 10 water swallows performed in the supine position. The aim of the study was to assess whether upright and provocative swallows (PS) provided important information beyond that obtained from the standard supine manometric protocol. Methods Two independent investigators reviewed high‐resolution manometry (HRM) studies of 148 patients with both supine and upright liquid swallows and additional studies from patients with PS (increased volume, viscosity, and a marshmallow) for a resultant change in CC diagnoses. Significant diagnostic changes were defined as a change from normal or borderline motor function to abnormal motor function, esophagogastric junction (EGJ) outflow obstruction, or achalasia. Discordant diagnoses were reviewed and the Kappa test was used to evaluate the agreement between diagnoses in the different protocols. Key Results The overall agreement in diagnosis between the five supine swallows and the five upright swallows was good (k = 0.583). Changing to the upright position elicited a significant diagnostic change in 10.1% (15/148) of cases. The PS suggested an alternative diagnosis from the supine position in 14 of 75 studies (18.7%); 11 of these changed to EGJ obstruction during viscous or solid bolus challenges. Conclusions & Inferences Changing position in HRM elicited a significant change in diagnosis in about 10% of studies, whereas provocative bolus challenges with viscous liquid and marshmallows increased the detection of EGJ outflow obstruction. Performing manometric evaluations in both positions with PS may increase the yield of standard HRM technique.