Pyloric-sphincter studies in peptic-ulcer patients: pylorus in peptic ulcer.

Pyloric pressure was assayed by a manometric procedure in the basal state and after intraduodenal infusion of HCl. 13 control subjects, 11 patients with benign gastric ulcer, 8 with duodenal ulcer, and 2 with coexistent gastric and duodenal ulcers were studied. Mean resting pyloric pressure in gastric-ulcer patients (5.17 +/- 0.71) mm Hg) was significantly lower than controls (9.40 +/- 0.85 mm Hg) and did not increase after HCl perfusion into the duodenum. Mean basal pyloric pressure in duodenal-ulcer patients (11.30 +/- 1.57 mm Hg) did not differ significantly from controls and increased after intraduodenal perfusion of HCl to 15.72 +/- 2.40 mm Hg. The two patients with coexistent ulcers had manometric patterns similar to gastric-ulcer patients. Decreased pyloric-sphincter pressure in gastric-ulcer patients may be the mechanism responsible for the increased duodeno-gastric reflux observed in these patients.