Characterization of esophageal striated muscle in patients with achalasia

Many studies have been conducted analyzing the manometric properties of patients with achalasia, but the striated portion of the esophagus has never been analyzed and is often overlooked. We retrospectively reviewed 120 manometric tracings (20 achalasia, 100 controls) performed between 1994 and 1997 and excluded tracings from patients with chronic cough and nutcracker esophagus. The data were assessed for age, sex, symptoms, duration of symptoms, lower esophageal sphincter pressure, gastroesophageal gradient, upper esophageal sphincter pressure, smooth muscle contraction amplitude and duration, striated muscle contraction amplitude and duration, length from upper esophageal sphincter to maximal striated muscle contraction, and esophageal length. The maximum striated muscle contraction amplitude was significantly decreased in achalasia patients with a median amplitude of 45 mm Hg (range 12-95) vs 76 mm Hg (range 30-210) in the control group (P = 0.002). Although the wave forms were similar, the maximum striated muscle contraction duration and the distance from the upper esophageal sphincter in achalasia patients was not significantly different from controls. The length of the esophagus was significantly longer in achalasia patients with a median value of 25 cm (range 21-30) vs 21 cm (range 17-26) in the control group (P < 0.001). Patients with achalasia have significantly lower maximum striated muscle contraction amplitudes and longer esophagi, but the duration of the contractions and the configuration of the wave forms are not different.