A Meta-Analysis of the Mechanism of Blood Pressure Change With Aging
Arun J. Baksi, MBBS*,
Thomas A. Treibel, MA, MBBS,
Justin E. Davies, MBBS, PhD,
Nearchos Hadjiloizou, MBBS,
Rodney A. Foale, MD,
Kim H. Parker, MA, PhD,
Darrel P. Francis, MD,
Jamil Mayet, MD and
Alun D. Hughes, MBBS, PhD
International Centre for Circulatory Health, St Mary's Hospital, Imperial College Healthcare NHS Trust and Imperial College London, London, United Kingdom
View larger version (21K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 2 Annotated Human Arterial Pulse Pressure Waveform
Arterial pressure waveform recorded from the human proximal aorta showing the foot of pressure waveform and a shoulder point due to arrival of a reflected wave. The time interval between these 2 points is the reflection time. The duration of systole is calculated as the time interval between the foot of the pressure waveform and the dicrotic notch. Augmentation pressure is the rise in pressure from the shoulder point to peak pressure.
|
|
View larger version (22K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 3 The Mean Timings Obtained From Each Cohort and 99% CI by Mean Age
This figure shows the mean time of arrival of the reflected wave (solid diamonds) and the mean duration of systole (open diamonds) for each cohort plotted by mean age. The horizontal bars denote 1 standard deviation. The regression line for the time of arrival of reflected wave with age is shown. The large solid diamond describes the mean and the 99% confidence interval (CI) for the weighted mean time of arrival of the reflected wave, and the large open diamond shows the mean and the 99% CI for the weighted mean time for the duration of systole.
|
|
View larger version (10K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 4 Large Increase in Augmentation Index Despite Only Modest Advance in Time of Arrival of Reflected Wave With Age
This figure shows the mean time of arrival of the reflected wave (solid diamonds) and the augmentation index (open circles) for each cohort plotted by mean age. The regression lines through these data show that relative to the duration of the cardiac cycle, the time of arrival of the reflected wave advances very little with increasing age, in comparison with augmentation index (shown relative to the theoretical maximum value of 50%), which increases >10-fold over the age range studied.
|
|
|
