Fatal Arrhythmogenic Right Ventricular Cardiomyopathy in 2 Related Subadult Chimpanzees (Pan troglodytes)

Abstract

Cardiovascular disease is increasingly recognized as an important cause of morbidity and mortality in captive chimpanzees (Pan troglodytes). This report records 2 cases of sudden cardiac death in closely related subadult captive chimpanzees with marked replacement fibrosis and adipocyte infiltration of the myocardium, which resemble specific atypical forms of the familial human disease arrhythmogenic right ventricular cardiomyopathy. Changes were consistent with left-dominant and biventricular subtypes, which are both phenotypic variants found within human families with familial arrhythmogenic right ventricular cardiomyopathy. Previously reported fibrosing cardiomyopathies in chimpanzees were characterized by nonspecific interstitial fibrosis, in contrast to the replacement fibrofatty infiltration with predilection for the outer myocardium seen in these 2 cases. To the authors' knowledge, this case report is the first to describe cardiomyopathy resembling arrhythmogenic right ventricular cardiomyopathy in nonhuman primates and the first to describe left-dominant arrhythmogenic cardiomyopathy-type lesions in an animal.

Unexpected Cardiac Death During Anaesthesia of a Young Rabbit Associated with Fibro-fatty Replacement of the Right Ventricular Myocardium

“…A dilated cardiomyopathy characterized by myocardial fibro-fatty replacement also occurs in young adult to mature Holstein cattle, with clinical signs particularly referable to right-sided heart failure, although there is no indication of the presence of electrocardiographical abnormalities (Robinson and Robinson, 2016). Furthermore, a similar condition causing sudden and unexpected cardiac death has been described in horses (Freel et al, 2010) and chimpanzees (Tong et al, 2014).…”

Clinical signs, diagnostics and successful treatment of a myocarditis in an adult chimpanzee (Pan troglodytes)

“…Viral myocarditis is known to be caused by picornaviruses, enteroviruses (particularly Coxsackie A and B), human herpes virus 6 (HHV‐6) and parvo B19 virus . Encephalomyocarditis and influenza virus infections are also reported as causative agent . Due to the vast variety of causative agents, it is often challenging to determine the exact cause of a myocarditis.…”

“…Cardiovascular disease (CVD) is the most prevalent cause of mortality in captive chimpanzees . Myocardial fibrosis, cardiomyopathies (dominantly left ventricular hypertrophy and dilated cardiomyopathy) and electrocardiographic abnormalities have since been observed in an increasing number of cases . There are very few documented cases of chimpanzee myocarditis available, and all are diagnosed post‐mortem .…”

“…1 Myocardial fibrosis, cardiomyopathies (dominantly left ventricular hypertrophy and dilated cardiomyopathy) and electrocardiographic abnormalities have since been observed in an increasing number of cases. [2][3][4][5][6][7][8] There are very few documented cases of chimpanzee myocarditis available, and all are diagnosed post-mortem. 9,10 Early diagnosis and onset of treatment is crucial for surviving myocarditis.…”

Natural pathology of the captive chimpanzee (Pan troglodytes): A 35‐year review

“…Except for a few short surveys of lesions and causes of mortality, an extensive documentation of chimpanzee lesions is lacking. Most of the published studies are in the form of case series that include pathology findings related to body systems (central nervous, cardiovascular, respiratory, gastrointestinal, urinary, and integumentary), etiologies (parasitic, degenerative, and neoplastic), and individual case reports . An extensive survey of the pathological lesions is lacking in literature.…”