RESUMO
We report a case of ventricular septal defect causing congestive heart failure in a two-year-old, male common degu (Octodon degus). The patient presented for anorexia and dental disease, and a grade 4/6 holosystolic cardiac murmur was detected on physical exam. Thoracic radiographs showed cardiomegaly and a diffuse interstitial pulmonary pattern, consistent with congestive heart failure. Echocardiography was supportive of a perimembranous ventricular septal defect exhibiting low-velocity left-to-right shunting, and biatrial enlargement. These diagnoses were confirmed on post-mortem exam, along with pulmonary edema and cardiomyocyte hypertrophy, degeneration, and regeneration. This is the first published account of a ventricular septal defect and congestive heart failure in a degu.