Human Technology Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki, Japan.
Hypertension. 2010 Nov;56(5):920-5. doi: 10.1161/HYPERTENSIONAHA.110.160549. Epub 2010 Sep 27.
An early return of reflected waves, the backward propagation of the arterial pressure wave from the periphery to the heart, is associated with the augmentation of central pulse pressure and cardiovascular risks. The locations of arterial pressure wave reflection, along with arterial stiffening, have a major influence on the timing of the reflected wave. To determine the influence of aging on the location of a major reflection site, arterial length (via 3D artery tracing of MRI) and central (carotid-femoral) and peripheral (femoral-ankle) pulse wave velocities were measured in 208 adults varying in age. The major reflection site was detected by carotid-femoral pulse wave velocity and the reflected wave transit time (via carotid arterial pressure wave analysis). The length from the aortic valve to the major reflection site (eg, effective reflecting length) significantly increased with aging. The effective reflecting length normalized by the arterial length demonstrated that the major reflection sites were located between the aortic bifurcation and femoral site in most of the subjects. The normalized effective reflecting length did not alter with aging until 65 years of age and increased remarkably thereafter in men and women. The effective reflecting length was significantly and positively associated with the difference between central and peripheral pulse wave velocities (r=0.76). This correlation remained significant even when the influence of aortic pulse wave velocity was partial out (r=0.35). These results suggest that the major reflection site shifts distally with aging partly because of the closer matching of impedance provided by central and peripheral arterial stiffness.
动脉压力波从外周向心脏的反向传播，即早期反射波，与中心脉搏压的增强和心血管风险相关。反射波的位置与动脉僵硬度一起，对反射波的时间有重大影响。为了确定衰老对主要反射部位位置的影响，对 208 名年龄不同的成年人进行了动脉长度（通过 MRI 的 3D 动脉追踪）和中心（颈股）及外周（股踝）脉搏波速度的测量。主要反射部位通过颈股脉搏波速度和反射波通过时间（通过颈动脉脉搏波分析）进行检测。从主动脉瓣到主要反射部位的距离（例如，有效反射长度）随年龄增长而显著增加。以动脉长度标准化的有效反射长度表明，在大多数受试者中，主要反射部位位于主动脉分叉和股部之间。在 65 岁之前，归一化有效反射长度不会随年龄变化而变化，之后在男性和女性中显著增加。有效反射长度与中心和外周脉搏波速度之间的差异呈显著正相关（r=0.76）。即使在部分考虑到主动脉脉搏波速度的影响后（r=0.35），这种相关性仍然显著。这些结果表明，主要反射部位随年龄的推移而向远端移动，部分原因是中心和外周动脉僵硬度提供的阻抗更加匹配。
