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.