P.19.3 ESOPHAGEAL HIGH RESOLUTION MANOMETRY FINDINGS DO NOT CORRELATE WITH CLEARANCE OF GASTRO-ESOPHAGEAL REFLUX IN GERD PATIENTS

Abstract

Ineffective esophageal motility (IEM) has been observed in erosive and non-erosive reflux disease (NERD) patients and may account for delayed bolus transit and impaired esophageal reflux clearance. It has been demonstrated that conventional manometry findings cannot predict reflux clearance in GERD patients. High resolution manometry (HRM) allows an accurate analysis of esophageal motility. Distal contractile integral (DCI) integrates the length, contractile vigour, and duration of contraction of the first two segments of the distal esophagus. Aim: To assess the correlation between HRM findings and reflux clearance in GERD patients. Methods: Following a 3-week washout from PPI and/or H2 antagonists, HRM and 24-hour ambulatory multichannel pH-impedance (pH-MII) monitoring were performed in 37 consecutive GERD patients, with no evidence of hiatal hernia at endoscopy. Patients were analyzed in the supine position, a catheter with 36 solid state pressure sensors located at 1 cm intervals (MMS, HRIM, Enschede, The Netherlands) was used. Data were stored and analyzed using dedicated software. A total of 10 saline (5 ml) swallows, at 30sec intervals were analyzed in each subject. The pH-impedance assembly was positioned with the pH electrode at 5cm above the LES and impedance measuring segments at 3, 5, 7, 9, 15 and 17cm above LES (Sandhill Scientific, USA). Reflux episodes were classified according to standardized criteria. Mean reflux clearance time (RCT) and reflux exposure time (RET) were calculated using Bioview software analysis, after a manual analisys of each pH-MII tracing. DCI was calculated and correlated to RCT and RET values by means of linear regression analysis. HRM tracings were analyzed according to the Chicago classification. IEM was defined by the presence of hypothensive or absent peristaltic waves in >20% of deglutitions. Results: Of the 37 patients, 30 showed normal esophageal motility and 7 IEM. Mean DCI values were 1562 (95% CI, 1203-1921) mmHg*s−1*cm−1 in all patients and 182 (95% CI, 122-242) mmHg*s−1*cm−1 in the 7 patients with IEM (p<0.001). Mean RCT and RET were 12.2 sec. and 3.6% of total recording time in all 37 patients, 13.5 sec. and 6.5% in the 7 IEM patients. No correlation was found between DCI and mean RCT and RET (r= 0.3 and 0.25, respectively). Weak correlation was found between DCI and mean RCT in the subgroup of IEM patients (r= 0.65, p<0.05). Conclusions: failure of esophageal motility seems to play a weak role in the clearing of gastroesophageal reflux episodes. DCI is not correlated to impaired esophageal reflux clearing whose occurrence could depend on the balance between the magnitude of the motility weakness and of the flow resistance at esophago-gastric junction.