Investigation of esophageal sensation and biomechanical properties in functional chest pain.

BACKGROUND: There is limited and conflicting data regarding the role of esophageal hypersensitivity in the pathogenesis of functional chest pain (FCP). We examined esophageal sensori-motor properties, mechanics, and symptoms in subjects with FCP.
METHODS: Esophageal balloon distension test was performed using impedance planimetry in 189 (m/f = 57/132) consecutive subjects with non-cardiac, non-reflux chest pain, and 36 (m/f = 16/20) healthy controls. The biomechanical and sensory properties of subjects with and without esophageal hypersensitivity were compared with controls. The frequency, intensity, and duration of chest pain were assessed. KEY
RESULTS: One hundred and forty-three (75%) subjects had esophageal hypersensitivity and 46 (25%) had normal sensitivity. Typical chest pain was reproduced in 105/143 (74%) subjects. Subjects with hypersensitivity demonstrated larger cross-sectional area (P < 0.001), decreased esophageal wall strain (P < 0.001) and distensibility (P < 0.001), and lower thresholds for perception (P < 0.01), discomfort (P < 0.01), and pain (P < 0.01) compared to those without hypersensitivity or healthy controls. Chest pain scores (mean +/- SD) for frequency, intensity and duration were 2.5 +/- 0.3, 2.2 +/- 0.2, and 2.2 +/- 0.2, respectively, and were similar between the two patient groups. CONCLUSIONS & INFERENCES: Seventy-five per cent of subjects with FCP demonstrate esophageal hypersensitivity. Visceral hyperalgesia and sensori-motor dysfunction of the esophagus play a key role in the pathogenesis of chest pain.