Topography of normal and high-amplitude esophageal peristalsis.

Topographic plots were created from esophageal manometric tracings in 12 asymptomatic volunteers and 10 symptomatic patients with high-amplitude peristaltic contraction waves (nutcracker esophagus) to identify segmental contraction differences between the two groups. Median waves at each centimeter of esophageal length were spatially interconnected using a computerized gridding and plotting system, and a characteristic peristaltic contraction from the proximal esophageal body through the lower sphincter was constructed for each subject. Contour plots in the volunteers revealed three amplitude troughs dividing the peristaltic contraction into four sequential segments: the skeletal muscle body, the proximal and distal segments of the smooth muscle body, and the lower sphincter region. In nutcracker-esophagus patients, only the first and third troughs could be identified, since augmented contraction in the distal smooth muscle segment blurred separation of the smooth muscle body segments. Volume measurements under the topographic plots showed no significant intergroup differences in contraction of the skeletal muscle region or lower sphincter but modest increase in contraction of the proximal smooth muscle segment [1.7 times normal, 95% confidence interval (CI) 1.2-2.0; P = 0.002 comparing 2 groups] and marked increase in the distal smooth muscle segment (2.7 times normal, 95% CI 2.0-3.3; P < 0.0001). These data indicate that normal peristalsis through the esophageal body and lower sphincter includes four separate contraction segments that can be distinguished with intraluminal manometry and the topographic analysis method. The nutcracker esophagus primarily affects the distal segment in the smooth muscle body.