Spontaneous heart disease in the adult chimpanzee (Pan troglodytes)

Background: A high incidence of heart disease, especially idiopathic cardiomyopathy (IC), is seen in chimpanzees (Pan troglodytes). Methods: We reviewed clinical records and necropsy reports of 87 adult chimpanzees for possible causes of heart disease/IC. We examined age, sex, cause of death, weight, diet, environment, infectious diseases, experimental uses and clinical pathology. Results: The overall prevalence of heart disease in chimpanzees was 67.81%; the prevalence of IC was 51.72%. The prevalence of IC was significantly higher in males (60.32%) than that in females (29.17%, P = 0.009). The prevalence of other heart disease was higher in females (25%) than that in males (12.70%, P = 0.165). Heart failure occurred in 47.13% of chimpanzees. Heart disease was the primary cause of death in 34.49% of chimpanzees; 29.88% died of unknown causes. Conclusions: We found no evidence that diet, environment, viral agents, experimental use or disease exposure contributed to the deaths resulting from IC in chimpanzees.