Infective aortic valve endocarditis in a cat with patent ductus arteriosus and perimembranous ventricular septal defect

A 3-year-old, male neutered, domestic short-haired cat presented for evaluation of respiratory distress. Transthoracic echocardiography revealed a left-to-right shunting ventricular septal defect, a left-to-right shunting patent ductus arteriosus, and a vegetative growth on the aortic valve leaflet consistent with aortic valve endocarditis. Because of poor response to therapy, the owner elected euthanasia, and a necropsy was performed. Gross necropsy examination confirmed the congenital cardiac defects, and aortic valve endocarditis was noted on the echocardiogram. Histopathological examination revealed diffuse interstitial pneumonia and evidence for systemic septic embolism including renal infarcts and brain microabscesses. To the authors' knowledge, this is the first case report of aortic valve endocarditis in a cat in association with congenital cardiac malformations.