Abstract
In this report, we described the clinical and pathological features of two dairy cows showing clinical signs of congestive heart failure. Case 1,a 2-year-old Holstein, showed anorexia, subcutaneous edema of the brisket, and bilateral jugular vein distension. Electrocardiograms showed decreased amplitude of the QRS complex. Echocardiography revealed markedly dilated cardiac chambers and poor left ventricular contractility. The clinical diagnosis based on these observations was dilated cardiomyopathy. Necropsy revealed thin ventricular free walls, and dilation of atrial and ventricular chambers. Microscopic examination of the heart showed enlargement, and vacuolar degeneration of myocytes and interstitial fibrosis, which coincided with the lesions of dilated cardiomyopathy, and this confirmed the diagnosis of dilated cardiomyopathy. Case 2,a 3-year-old Holstein, showed anorexia, subcutaneous edema of the brisket, and bilateral jugular vein distension. Echocardiography revealed left ventricular dilation, increased aortic root diameter, right ventricular diastolic insufficiency arising from myocardial effusion, and lack of coaptation of the aortic valve cusps. Pathological examination of the heart showed left ventricular dilation, increased aortic root diameter, and thickening of the cusps of the aortic valve associated with myxomatous degeneration. The clinical diagnosis based on these observations was aortic valve insufficiency.
