BACKGROUND: This study defines the entity of the hypertensive lower esophageal sphincter (HLES) and its treatment, including surgical implications. METHODS: Esophageal manometry was performed on 1,300 patients, Of these, 53 (4%) had HLES with resting pressure >26.5 mm Hg, defined as the upper limit of normal resting LES pressure. Thirty-two of these patients had 24-hour esophageal pH studies. The response to treatment was assessed. RESULTS: Fourteen patients (26%) with HLES had achalasia. Of the remaining 39 (74%), 25 had an isolated HLES with normal esophageal body motility, 5 had a nonspecific esophageal motility disorders (NEMD), 4 were post-Nissen fundoplication, 3 had a nutcracker esophagus, and 2 had diffuse esophageal spasm (DES). Nineteen percent of HLES patients had gastroesophageal reflux on pH studies. Eighty-two percent of HLES patients responded well to symptom-directed medical therapy. Two patients with esophageal body dysmotility responded well to an esophageal myotomy with a partial fundoplication. CONCLUSIONS: Patients with the HLES form a heterogeneous group. Gastroesophageal reflux in HLES patients is not uncommon. Patients with HLES respond well to medical therapy. Carefully selected patients require surgery. (C) 1996 by Excerpta Medica, Inc.