Esophagogastric junction contractile integral (EGJ-CI) complements reflux disease severity and provides insight into the pathophysiology of reflux disease.

Abstract

Esophagogastric junction contractile integral (EGJ-CI) has not come into routine use due to methodological discrepancies and its unclear clinical utility. We aimed to determine which method of calculating EGJ-CI was best at discriminating between common reflux disease states. High-resolution manometry (HRM) and pH-Impedance measurements were acquired for 100 patients; 25 Barrett's esophagus (>3 cm/acid exposure time (AET) > 6), 25 endoscopy-negative reflux disease (ENRD; AET >6), 25 borderline reflux (AET 4-6), 25 functional heartburn (FH; AET <4), constituting the developmental cohort. EGJ-CI was calculated at 20 mmHg, 2 mmHg, and 0 mmHg isobaric contour. Empirical associations, univariable, multivariable and ROC analyses were performed between EGJ-CI and manometric/pH-impedance metrics. A validation cohort (n = 25) was used to test the new EGJ-CI cutoff. Significant correlations with AET were observed when EGJ-CI was calculated with an isobaric threshold of 20 mmHg (p < 0.001). Significant differences in EGJ-CI were observed between patients with FH and Barrett's esophagus (p = 0.004) and with ENRD (p = 0.01); however, LES basal pressure was unable to differentiate between these disease states (p = 0.09, p = 0.25, respectively). ROC analysis on the developmental cohort found that EGJ-CI 21.2 mmHg.cm demonstrated sensitivity 72% and specificity 72% between patients with reflux (Barrett's esophagus/ENRD) and FH. In the validation cohort, 92.8% with a low EGJ-CI had good/moderate improvement in symptoms following therapy compared to 54.5% with raised EGJ-CI (p = 0.026). This study re-affirms EGJ-CI as a reliable discriminator between reflux disease (Barrett's esophagus/ENRD) and FH. In borderline reflux patients, patients with a lower EGJ-CI score (<21.2 mmHg) appear to respond better to anti-reflux therapies compared to those with a higher value.