What's a "normal" resting heart rate?  Can it change as a result of age or medical conditions such as high blood pressure?
D000367:Age Factors; D000375:Aging; D001794:Blood Pressure; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D006973:Hypertension / Q000503:physiopathology*; D012307:Risk Factors