Vascular ring anomalies
Vascular ring anomalies occur when the embryonic aortic arches develop abnormally so that a “vascular ring” is formed that constricts the esophagus. The most common anomaly is a persistent right aortic arch, where the esophagus is entrapped between the heart, the abnormally formed aorta on the right, the pulmonary artery, and the ligamentum arteriosus, which connects the aorta and pulmonary artery.81,82 Other vascular ring anomalies that have been reported in dogs and cats include a double aortic arch, anomalous right patent ductus arteriosus, and coarctation of the aorta with an aberrant left subclavian artery.83-86
The clinical signs are associated with obstruction of the esophagus and aspiration pneumonia, and include onset of regurgitation at the time of weaning, coughing, and lethargy.
A dilated esophagus filled with food may be palpated in the cervical region. Diagnosis is made on survey thoracic radiographs, which show a focally distended esophagus with an abrupt narrowing of the esophagus at the heart base. Surgical transection of the constricting bands around the esophagus is the treatment of choice.82,83,85 This procedure has recently been successfully performed by thoracoscopy.87 Prognosis for full recovery is good, but some dogs have a persistently dilated esophagus that does not return to normal size or function 82,83,85,86Key Facts
■ Regardless of the diagnosis, clinical signs of esophageal disease are often similar and include regurgitation, ptyalism, and dysphagia.
■ Videofluoroscopy is the diagnostic test of choice to help diagnose esophageal motility disorders.
■ Esophagoscopy can be an invaluable tool in the diagnosis and therapy of various esophageal diseases.
■ Esophagitis is commonly treated with H2-receptor antagonists or a proton pump inhibitor, sucralfate suspension, and a prokinetic agent. A gastrostomy tube may be needed for nutritional support in some patients.