Rapid Drink Challenge During High-resolution Manometry for Evaluation of Esophageal Emptying in Treated Achalasia

BACKGROUND & AIMS

Incomplete esophageal emptying is a key variable predicting symptom relapse after achalasia treatment. Although optimally evaluated using the timed barium esophagogram (TBE), incomplete esophageal emptying can also be identified on rapid drink challenge (RDC) performed during high-resolution manometry.

METHODS

We evaluated if RDC differentiates complete from incomplete esophageal emptying in treated patients with achalasia, against a TBE gold standard. Unselected treated patients with achalasia with both TBE (200 mL of low-density barium suspension) and RDC (200 mL of water in sitting position) were enrolled in 5 tertiary referral centers. TBE barium column height at 1, 2, and 5 minutes were compared with RDC variables: pressurizations >20 mmHg, maximal RDC pressurization, proportion of RDC time occupied by pressurizations, trans-esophagogastric junction gradient, and integrated relaxation pressure.

RESULTS

Of 175 patients recruited (mean age, 59 years; 47% female), 138 (79%) were in clinical remission. Complete TBE emptying occurred in 45.1% at 1 minute, 64.0% at 2 minutes, and 73.1% at 5 minutes. RDC integrated relaxation pressure correlated strongly with TBE column height, and a 10-mmHg threshold discriminated complete from incomplete emptying at all 3 TBE time points with area under receiver operating characteristic curves of 0.85, 0.87, and 0.85, respectively. This threshold had high negative predictive values for complete emptying (88% at 2 minutes, 94% at 5 minutes), and modest positive predictive values for incomplete emptying (77% at 2 minutes, 62% at 5 minutes).

CONCLUSIONS

RDC during high-resolution manometry is an effective surrogate for TBE in assessing esophageal emptying in treated patients with achalasia.

Rapid Drink Challenge in high-resolution manometry: an adjunctive test for detection of esophageal motility disorders

BACKGROUND/AIMS

The Chicago Classification for diagnosis of esophageal motility disorders by high-resolution manometry (HRM) is based on single water swallows (SWS). Emerging data suggest that a "Rapid Drink Challenge" (RDC) increases sensitivity for motility disorders. This study establishes normal values and diagnostic thresholds for RDC in clinical practice.

METHODS

Two cohort studies were performed in patients with dysphagia or reflux symptoms (development and validation sets). Healthy subjects and patient controls provided reference values. Ten SWS and two 200-mL RDC were performed. Primary diagnosis for SWS was established by the Chicago Classification. Abnormal RDC was defined by impaired esophagogastric junction (EGJ) function (elevated integrated relaxation pressure during RDC [IRP-RDC]); incomplete inhibition of contractility during and ineffective contraction after RDC. Diagnostic thresholds identified in the development set were prospectively tested in the validation set.

RESULTS

Normal values were determined in healthy (n=95; age 37.8 ± 12) and patient controls (n=44; age 46.4 ± 15). Development and validation sets included 178 (54 ± 17 years) and 226 (53 ± 16 years) patients, respectively. Integrated relaxation pressure during RDC was higher for SWS than RDC in all groups (overall P<.001), except achalasia. Rapid Drink Challenge suppressed contractility, except in achalasia type III, spasm, and hypercontractile motility disorders (P<.001). An effective after-contraction was present more often in health than disease (P<.001). Optimal diagnostic thresholds identified in the development set (IRP-RDC ≥12 mmHg achalasia, IRP-RDC ≥ 8mmHg "all cause" EGJ dysfunction), were confirmed in the validation set (both, sensitivity ~85%, specificity >95%).

CONCLUSIONS

Rapid Drink Challenge contributes clinically relevant information to routine HRM studies, especially in patients with EGJ dysfunction.