High-Resolution Impedance Manometry Metrics of the Esophagogastric Junction for the Assessment of Treatment Response in Achalasia

Abstract

Objective We aimed to evaluate the value of novel high-resolution impedance manometry (HRIM) metrics, bolus flow time (BFT) and esophagogastric junction (EGJ) contractile integral (CI), as well as EGJ pressure (EGJP) and the integrated relaxation pressure (IRP), as indicators of treatment response in achalasia. Design We prospectively evaluated 75 patients (ages 19–81, 32 female) with achalasia during follow-up after pneumatic dilation or myotomy with Eckardt score (ES), timed-barium esophagram (TBE), and HRIM. Receiver-operating characteristic (ROC) curves for good symptomatic outcome (ES ≤ 3) and good radiographic outcome (TBE column height at 5 minutes < 5 cm) were generated for each potential predictor of treatment response (EGJP, IRP, BFT, and EGJ-CI). Results Follow-up occurred at a median (range) 12 (3 – 291) months following treatment. 49 patients had good symptomatic outcome and 46 had good radiographic outcome. The area-under-the-curves (AUCs) on the ROC curve for symptomatic outcome were 0.55 (EGJP), 0.62 (IRP), 0.77 (BFT) and 0.56 (EGJ-CI). The AUCs for radiographic outcome were 0.64 (EGJP), 0.48 (IRP), 0.73 (BFT), and 0.65 (EGJ-CI). Optimal cut-points were determined as 11 mmHg (EGJP) 12 mmHg (IRP), zero seconds (BFT), and 30 mmHg•cm (EGJ-CI) that provided sensitivities/specificities of 57%/46% (EGJP), 65%/58% (IRP), 78%/77% (BFT), and 53%/62% (EGJ-CI) to predict symptomatic outcome and 57%/66% (EGJP), 57%/41% (IRP), 76%/69% (BFT), and 57%/66% (EGJ-CI) to predict radiographic outcome. Conclusions BFT, a novel HRIM metric, provided an improved functional assessment over manometric measures of EGJP, IRP, and EGJ-CI at follow-up after achalasia treatment and may help direct clinical management.

A study of dysphagia symptoms and esophageal body function in children undergoing anti‐reflux surgery

“…Interestingly, in the subgroup of patients for whom preand post-operative HRIM data was available, fundoplication increased EGJ resistance but had little or no effect on clearance pressures. Bolus flow time, a parameter which is typically shorter in nonobstructive dysphagia 37 and achalasia 48,49 , was paradoxically longer in relation to dysphagia in our study. Furthermore, the IRP4 parameter used to diagnose EGJ outflow obstruction was not associated with dysphagia.…”

High-resolution esophageal manometry

“…30 HRIM metrics examining bolus transit include the esophageal impedance integral as a surrogate for bolus retention 31 , intrabolus pressure as a marker of esophageal wall state during bolus transit 32 , and bolus flow time as a measurement of trans-EGJ pressure gradients during flow. 33, 34 Post-prandial HRIM also provides valuable information about manometric responses to digestive stimuli such as transient LES relaxation episodes, rumination syndrome, and belching disorders. 35–37 …”

Inter‐rater agreement of novel high‐resolution impedance manometry metrics: Bolus flow time and esophageal impedance integral ratio

“…The HRIM data for each subject were exported to MATLAB ™ to apply to a customized program for analysis of BFT and EII ratio as previously described; Figure 1. 9, 10 …”

“…6,7 Both the BFT and EII ratio demonstrated promise with enhanced symptomassociation over other manometric measures among patients with achalasia and also with non-obstructive dysphagia without a major esophageal motility disorder. [8][9][10] However, inter-rater reliability of Abbreviations: AIM, automated impedance manometry; BPT, bolus presence time; BFT, bolus flow time; CD, crural diaphragm; EGJ, esophagogastric junction; EII, esophageal impedance integral; HRIM, high-resolution impedance manometry; ICC, intraclass correlation coefficient; IRP, integrated relaxation pressure. the analysis to generate the BFT and EII ratio has not been assessed and thus the aim of this study was to evaluate the inter-rater agreement of the BFT and EII ratio among a cohort of patients evaluated for dysphagia.…”

“…Median (per-patient) values generated by one rater were median (inter-quartile range) 16(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22) mm Hg for IRP, 1.3 (0-3) seconds for bolus presence time, 0.2 (0-1.1) seconds for BFT, and 0.33 (0-0.52) for EII ratio and were similar (ie all P > .05) than those generated by the other rater: 15 (8-22) mm Hg for IRP, 1.6 (0.1-3.2) seconds for BPT, 0.7 (0-1.6) seconds for BFT, and 0.30 (0.05-0.51) for EII ratio. Intraclass correlation coefficients demonstrated strong to almost perfect agreement of each metric whether evaluating median values (n = 40) or all upright swallows (n = 200); Table 1.…”