Abstracts
1997 Digestive Disease Week

Association of lower esophageal sphincter length with postprandial gastroesophageal reflux.

RJ Mason, MP Ritter, M Gadenstatter, CG Bremner, JH Peters, TR DeMeester. Department of Surgery, University Southern California, Los Angeles, CA.

Loss of sphincter length and competency during gastric distension and its prevention by fundoplication has recently been demonstrated in an animal model. Intuitively, this concept suggests that patients with shorter resting sphincter lengths should have more gastroesophageal reflux after a meal than those with longer sphincter lengths. The aim of the study was to test the hypothesis by measuring the number, duration and frequency of reflux episodes (pH < 4) that occurred 2 hours following a meal in the first 500 consecutive unselected patients who had undergone both manometry and subsequent 24 hr pH monitoring of the esophagus in our laboratory, and to correlated this with sphincter length. This group included 415 patients with reflux symptoms, 55 normal volunteers and 30 patients following an antireflux procedure. Forty four percent (220/500) of this group had pathologically increased esophageal acid exposure ( 4.4% Total Time pH< 4). Postprandial gastroesophageal reflux was significantly greater in patients than in normal or postop patients (Table, Median ± IQR *p< 0.05)

           No.   LES Length     % Time pH < 4     No of reflux episodes
                                postprandially       postprandially
Normal     55     3.2 ± 0.8      1.45 ± 3.92           5.5 ± 14.5
Patients   415    2.6 ± 1.5 *     7.6 ± 16.05 *         18 ± 30.5 *
Postop     30     3.4 ± 1.08      0.0 ± 0.6            0.0 ± 3

A significant correlation was found between the initial sphincter length (r = -0.93) and the abdominal sphincter length (r= -0.92) and reflux after a meal (Figure). The correlation was less strong with the other periods (supine period r = - 0.69, upright period r = - 0.77). This study reinforces the dominant role of sphincter length in reflux disease and the need to restore length to normal and prevent unfolding during distension. [Figure not available.]