King's College London, British Heart Foundation Centre, London.
Brunel Institute for Bioengineering, Brunel University, Uxbridge, Middlesex, UK.
J Hypertens. 2019 Feb;37(2):347-355. doi: 10.1097/HJH.0000000000001886.
The aim of this study was to investigate the effect of age and sex on nPWV and ndI in the ascending aorta of healthy humans.
Local pulse wave velocity (nPWV) and wave intensity (ndI) in the human ascending aorta have not been studied adequately, because of the need for invasive pressure measurements. However, a recently developed technique made the noninvasive determination of nPWV and ndI possible using measurements of flow velocity and arterial diameter.
Diameter and flow velocity were measured at the level of the ascending aorta in 144 healthy participants (aged 20-77 years, 66 men), using MRI. nPWV, ndI parameters; forward (FCW); backward (BCW) compression waves, forward decompression wave (FDW), local aortic distensibility (nDs) and reflection index (nRI) were calculated.
nPWV increased significantly with age from 4.7 ± 0.3 m/s for those 20-30 years to 6.4 ± 0.2 m/s for those 70-80 years (P < 0.001) and did not differ between sexes. nDs decreased with age (5.3 ± 0.5 vs. 2.6 ± 0.2 10 1/Pa, P < 0.001) and nRI increased with age (0.17 ± 0.03 vs. 0.39 ± 0.06, P < 0.01) for those 20-30 and 70-80 years, respectively. FCW, BCW and FDW decreased significantly with age by 86.3, 71.3 and 74.2%, respectively (P < 0.001), all compared to the lowest age-band.
In healthy humans, ageing results in stiffer ascending aorta, with increase in nPWV and decrease in nDs. A decrease in FCW and FDW indicates decline in left ventricular early and late systolic functions with age in healthy humans with no differences between sexes. nRI is more sensitive than BCW in establishing the effects of ageing on reflected waves measured in the ascending aorta.
本研究旨在探讨年龄和性别对健康人体升主动脉近端脉搏波速度（nPWV）和近端脉搏波强度（ndI）的影响。
由于需要进行有创压力测量，因此尚未充分研究人体升主动脉的局部脉搏波速度（nPWV）和波强度（ndI）。然而，最近开发的一种技术使得使用流速和动脉直径测量来无创地确定 nPWV 和 ndI 成为可能。
使用 MRI 在 144 名健康参与者（年龄 20-77 岁，66 名男性）的升主动脉水平测量直径和流速。计算 nPWV、ndI 参数；正向（FCW）；反向（BCW）压缩波，正向减压波（FDW），局部主动脉顺应性（nDs）和反射指数（nRI）。
nPWV 随年龄显著增加，从 20-30 岁的 4.7±0.3m/s 增加到 70-80 岁的 6.4±0.2m/s（P<0.001），且不受性别影响。nDs 随年龄降低（5.3±0.5 与 2.6±0.2 10¹/Pa，P<0.001），nRI 随年龄增加（0.17±0.03 与 0.39±0.06，P<0.01），分别为 20-30 岁和 70-80 岁。FCW、BCW 和 FDW 分别显著随年龄下降 86.3%、71.3%和 74.2%（P<0.001），均与最低年龄组相比。
在健康人群中，衰老导致升主动脉变硬，nPWV 增加，nDs 降低。FCW 和 FDW 的降低表明，在没有性别的情况下，健康人群的左心室早期和晚期收缩功能随年龄增长而下降。nRI 比 BCW 更能反映年龄对升主动脉反射波的影响。
