Aortic Insufficiency Associated with Ventricular Septal Defect in a Heifer

Abstract

A 28-month-old Holstein heifer was affected with aortic insufficiency associated with ventricular septal defect. She manifested tachycardia with a systolic and diastolic cardiac murmur, marked carotid pulsation at the base of the neck, prominent palpable cardiac impulse over the left thoracic wall, tachypnea on exercise, and abnormal ECG pattern suggesting cardiac hypertrophy.
Necropsy revealed a ventricular septal defect (1.5 cm in diameter) at the base of the aortic valve. The right aortic cusp, deformed and thickened, had prolapsed into the ventricular septal defect, causing aortic insufficiency. Two other aortic cusps were also thickened and distorted.