title: Alteration of cardiac function in a single subject studied repeatedly between the ages of 41 and 78 years.
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000375:Aging; D001450:Ballistocardiography; D005500:Follow-Up Studies; D006321:Heart / Q000502:physiology*; D006801:Humans; D008875:Middle Aged; D010414:Pennsylvania