Automated impedance‐manometry analysis detects esophageal motor dysfunction in patients who have non‐obstructive dysphagia with normal manometry

Background Automated integrated analysis of impedance and pressure signals has been reported to identify patients at risk of developing dysphagia post fundoplication. This study aimed to investigate this analysis in the evaluation of patients with non‐obstructive dysphagia (NOD) and normal manometry (NOD/NM). Methods Combined impedance‐manometry was performed in 42 patients (27F : 15M; 56.2 ± 5.1 years) and compared with that of 24 healthy subjects (8F : 16M; 48.2 ± 2.9 years). Both liquid and viscous boluses were tested. MATLAB‐based algorithms defined the median intrabolus pressure (IBP), IBP slope, peak pressure (PP), and timing of bolus flow relative to peak pressure (TNadImp‐PP). An index of pressure and flow (PFI) in the distal esophagus was derived from these variables. Key Results Diagnoses based on conventional manometric assessment: diffuse spasm (n = 5), non‐specific motor disorders (n = 19), and normal (n = 11). Patients with achalasia (n = 7) were excluded from automated impedance‐manometry (AIM) analysis. Only 2/11 (18%) patients with NOD/NM had evidence of flow abnormality on conventional impedance analysis. Several variables derived by integrated impedance‐pressure analysis were significantly different in patients as compared with healthy: higher PNadImp (P