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.