Brown atrophy of the heart is atrophy of the heart muscle (or myocardium) commonly found in the elderly. It is described as brown because fibers become pigmented by intracellular lipofuscin deposits (mostly around the cell nucleus) a type of lipochrome granule.
It has no known effect on function, and is described as being expected or normal in aging.
Other types of brown atrophy include brown atrophy of neuronia and brown atrophy of the liver.
References
Brown atrophy of the heart Wikipedia(Text) CC BY-SA