Abstract
A 10-month-old, 8.5-kg female intact Shiba dog was referred to the Azabu University Veterinary Teaching Hospital for further examination of congestive heart failure. At the time of first presentation, the dog appeared thin and mildly depressed. A Levine grade V/VI systolic ejection murmur and III/VI regurgitant murmur were heard loudest with point at the heart base of the left side and at the right sternal border, respectively. Radiography revealed dilatation of the main pulmonary artery, and enlargement of the right atrial and biventricular. Echocardiography demonstrated the ventricular septal defect (VSD) and pulmonary valvular stenosis (PS) with right ventricular hypertrophy.
Pulmonay artery banding is one of the treatments for VSD. The hemodynamic conditions of the present case resemble those of a VSD case with pulmonary artery banding. Because obvious hemodynamic changes have not been noticed for about 1 year, the shunt rate of VSD seems to be appropriately controlled by PS. However, although PS may prevent left heart failure caused by VSD, progressive right heart failure may be gradually advances. Therefore, complete surgical correction with pulmonary bypass is necessary before right heart failure advances.
