Pressure-impedance analysis: Assist the diagnosis and classification of ineffective esophageal motility disorder

Background and Aim We elucidated the clinical significance of distal contractile integral-to-esophageal impedance integral (EII) ratio (DCIIR) in ineffective esophageal motility (IEM) adult patients. Methods We recruited 101 patients with IEM (48.38 +/- 1.58 years) and 42 matched healthy volunteers (44.28 +/- 1.85 years) in this case-control study. All subjects underwent esophageal high-resolution impedance manometry from October 2014 to May 2018. The diagnosis of IEM was based on the Chicago Classification version 3.0. The EII, EII ratio, and DCIIR were analyzed by matlab software. Results The EII, EII ratio, and DCIIR calculated at an impedance threshold of 1500 omega (EII1500, EII ratio1500, and DCIIR1500, respectively) were significantly lower in the IEM group than in healthy controls (P < 0.0001, < 0.0001, and < 0.0001, respectively). Receiver operating characteristic analysis showed that DCIIR1500 < 0.008 mmHg/omega, EII1500 > 71 000 omega.s.cm, and EII ratio1500 > 0.43 were all predictive of IEM. Only DCIIR1500 < 0.008 mmHg/omega remained significant in diagnosing IEM in the multivariate logistic regression analysis (odds ratio = 72.13, P < 0.001). The DCIIR1500 is negatively correlated with Eckardt score and the Reflux Disease Questionnaire (correlation coefficient = -0.2844 and -0.3136; P = 0.0006 and 0.0002, respectively). Receiver operating characteristic analysis further showed that a DCIIR1500 cut-off of 0.002 mmHg/omega achieved the best differentiation between the IEM-alternans and IEM-persistens subtypes among IEM patients (P < 0.001). Conclusions The novel pressure-impedance parameter of high-resolution impedance manometry, DCIIR1500, may assist in the diagnosis and classification of IEM and correlated with clinical symptoms.