A 3-week-old female white Bengal Tiger cub (Panthera tigris tigris) presented 
with acute onset tachypnoea, cyanosis and hypothermia. The cub was severely 
hypoxaemic with a mixed acid-base disturbance. Echocardiography revealed severe 
pulmonic stenosis, right ventricular hypertrophy, high membranous ventricular 
septal defect and an overriding aorta. Additionally, an atrial septal defect was 
found on necropsy, resulting in the final diagnosis of Tetralogy of Fallot with 
an atrial septal defect (a subclass of Pentalogy of Fallot). This report is the 
first to encompass arterial blood gas analysis, thoracic radiographs, 
echocardiography and necropsy findings in a white Bengal Tiger cub diagnosed 
with Tetralogy of Fallot with an atrial septal defect.