Tracking of brachial and central aortic systolic pressure over the normal human lifespan: insight from the arterial pulse waveforms.

Despite multiple studies, it has not been possible to account for the normal changes of blood pressure that occur from infancy to old age. We sought a comprehensive explanation, by linking brachial pressure with the well documented changes in the arterial pulse waveform, whose peak and nadir determine systolic, diastolic and pulse pressure in brachial arteries. Changes in humans arterial pulse wave contour from birth to old age can be readily explained on (i) growth, with increasing length of the body from birth to adolescence, and adult height maintained thereafter, and (ii) degeneration and dilation of the aorta from elastic fibre fracture throughout life, causing progressive increase in aortic pressure wave amplitude from early return of wave reflection, and summation of incident with reflected waves in systole. These changes throughout life complement arterial pulse waveform analysis and explain brachial cuff pressure values, with optimal pulse wave pattern for cardiac interaction apparent in adolescence.