2 NECROPSY CASES OF HYPERTROPHIC CARDIOMYOPATHY IN HOLSTEIN CATTLE

Two cases of hypertrophic cardiomyopathy in Holstein dairy cows are pr esented. At necropsy, the hearts revealed proportionate hypertrophy of the entire ventricles. The cut surface showed relatively large areas of myocardial scarring scattered throughout the ventricular walls incl uding the septum. Microscopic examination revealed marked disorganizat ion of cardiac muscle cells, intramural coronary arteries with thicken ed walls and narrowed lumina, and pronounced myocardial fibrosis. Thes e features resemble those of hypertrophic cardiomyopathy in humans, su ggesting the presence of a similar primary myocardial disease in cattl e.