Esophageal pressure topography criteria indicative of incomplete bolus clearance: a study using high-resolution impedance manometry.

OBJECTIVES: This study used high-resolution impedance manometry (HRIM) to determine pressure topography thresholds of peristaltic integrity predictive of incomplete esophageal bolus clearance.
METHODS: A total of 16 normal controls and 8 patients with dysphagia were studied using a solid-state HRIM assembly incorporating 36 manometric sensors and 12 impedance segments. Each of the 10 saline swallows in each study was dichotomously scored as either complete or incomplete bolus clearance by impedance criteria, and peristaltic integrity was evaluated using pressure topography isobaric contours ranging from 10 to 30 mm Hg in 5- mm Hg increments. Each isobaric contour plot was characterized by the location and length of breaks in the isobaric contour.
RESULTS: All subjects had normal esophagogastric junction (EGJ) relaxation and none met the pressure topography criteria of hiatus hernia. In all, 70 (29%) of the 240 individual swallows had incomplete bolus clearance. In every case, an intact >or=20 mm Hg isobaric contour was associated with complete bolus clearance. The largest defect in the 20 and 30 mm Hg isobaric contours associated with complete bolus clearance measured 1.7 and 3.0 cm, respectively, in length, whereas the smallest defect predictive of incomplete bolus clearance measured 2.1 and 3.2 cm, respectively.
CONCLUSIONS: In individuals with normal EGJ relaxation and morphology, peristaltic contractions with breaks <2 cm in the 20 mm Hg isobaric contour or <3 cm in the 30 mm Hg isobaric contour are associated with complete bolus clearance, and longer breaks predict incomplete bolus clearance.