The Evolution of the Sinus Heart Rate and Variability as a Function of Age from Birth to 16 Years

From our experience with adults, the study of heart rate has appeared to be fundamental in the appreciation of the alterations in adrenergic and vagal tone with age. The purpose of this study, therefore, is to evaluate the sinus heart rate-age relationship from birth to midadolescence to establish normal values and to offer an optimal approach to the postnatal maturation and spontaneous development of the cardiovascular regulatory nervous system.