Yerkes Researchers Find Different Types of Heart Disease in Humans and Chimpanzees

Researchers at the Yerkes National Primate Research Center and University of California, San Diego, have found distinctly different causes of “heart attacks” experienced by humans and chimpanzees. Both chimpanzees and humans may die from heart disease without advance warning, a happening known as sudden cardiac death. In humans, heart disease is most frequently associated with atherosclerosis, blockage of blood vessels of the heart leading to loss of oxygen to heart tissues.

In chimpanzees, however, sudden death is not associated with atherosclerosis, but rather with a condition known as interstitial myocardial fibrosis. Fibrosis is scarring of the heart tissue. While the disease is commonly associated with coronary heart disease in humans, it is not thought to lead to sudden death. In chimpanzees, an interstitial component means simply that scarring occurs between heart muscles in the interstitium of the heart, the normal connective tissue that separates heart muscle fibers. The cause for scarring in this area of the chimpanzee heart is unknown. Sudden death in chimpanzees due to interstitial myocardial fibrosis happens much more commonly in male chimpanzees than in female chimpanzees, with sudden deaths in males happening at a relatively early age, late teens to early 30s.

The study, which aims to understand the evolutionary differences between the most common cause of death in both humans and chimpanzees, is available in the current issue of Evolutionary Applications