Bovine dilated cardiomyopathy with overlapping myocarditis in an adult Holstein-Friesian dairy cow

AbstractIn humans, it is acknowledged that dilated cardiomyopathy is also caused by infection-induced myocarditis. To evaluate whether the occurrence of lesions of dilated cardiomyopathy in cattle may be triggered by myocarditis, an adult Holstein-Friesian dairy cow which showed dilated cardiomyopathy associated with myocarditis was examined by histopathology. Traumatic pericarditis or idiopathic congestive heart failure was clinically suspected, and the animal was culled because of unfavorable prognosis. Histopathological examination revealed an intrinsic cardiomyopathic lesion that overlapped with myocarditis. Cardiomyocytes had sarcoplasmic vacuoles containing amorphous materials and/or lipofuscin granules, which were consistent with autophagic vacuoles. Inflammatory cells, such as lymphocytes and neutrophils, infiltrated the myocardium and sub-pericardial regions. Even though the pathogenetical mechanism of dilated cardiomyopathy following myocarditis in humans may not necessarily be applicable to that of the hereditarily determined dilated cardiomyopathy in the cow, the myocardium of latter showed histopathological features similar to some degree to those of the human heart disease. To confirm whether the inflammatory process may have played a role as a trigger (or promoting) factor for initiating cardiomyopathic lesions of this cow, further research of substantial numbers of relevant bovine cases appears warranted.
Source: Comparative Clinical Pathology - Category: Pathology Source Type: research