Besides hiatal hernia (see Congenital and Inherited Anomalies of the Digestive System: Hernias) the most common abnormality involving the stomach with a suspect heritable etiology is pyloric stenosis. Pyloric stenosis or hypertrophy results from muscular thickening of the pyloric sphincter, which obstructs pyloric outflow. Affected breeds include brachycephalic and smaller breeds, especially Boxers and Boston Terriers, as well as Siamese cats. Clinical signs reflect delayed gastric emptying and usually manifest as vomiting of food several hours after a meal. Treatment is through dietary modification and motility modifiers, such as metoclopramide or cisapride. In more severely affected cases, pyloromyotomy may be beneficial.

Fig. 1
Pyloric stenosis, pyloromyotomy site. Illustration by Dr. Gheorghe Constantinescu.

Last full review/revision March 2012 by Walter Ingwersen, DVM, DVSc, DACVIM