Aging of the heart has not impressed the physician, although the striking anatomic change, brown atrophy, has long been known and recently has been emphasized by quantitative studies.1 The electron microscope has shown that there are comparable changes in the mitochondria,2 and the biochemists measure the decline in the enzymes needed to maintain contraction.3 The nervous elements also atrophy,4 so that the heart can less effectively mobilize the catecholamines which augment the speed and force of contraction when the circulatory needs are increased by stress. The observations of I. Starr and his disciples on the change in headfoot ballistocardiograms and pulse contours in an aging "normal" population,5,6 and those of Harrison's group on the motion of the precordium,7 seem to point to a steady decline in the force of contraction and rise in resistance to diastolic filling, from nonage to nonagenarity.
The data on
Dock W. How Some Hearts Age. JAMA. 1966;195(6):442-444. doi:10.1001/jama.1966.03100060082024