Double-Outlet Right Ventricular Malformation in a Two-Year-Old Aberdeen Angus Cow.

A 2-year-old Aberdeen Angus cow was presented with lethargy and decreased appetite at the VA-MD College of Veterinary Medicine Large Animal Teaching Hospital. Initial clinical examination revealed cyanosis, tachycardia, polycythemia, and a significant increase in lactate levels. The heifer experienced spontaneous death while hospitalized, prompting a postmortem examination. Gross evaluation demonstrated that the aorta arose entirely from the right ventricle, while the main pulmonary artery maintained its normal position, consistent with a diagnosis of double-outlet right ventricle. Additional cardiac abnormalities were identified, including an atrial septal defect, ventricular septal defect and marked right ventricular hypertrophy. These defects fall under the category of double-outlet right ventricle malformation. While congenital heart defects are a more recognized cause of cardiac failure and mortality in calves, they should remain a consideration in cases of sudden death, even in adult cattle.