AGE ASSOCIATED CHANGES IN VASCULAR STIFFNESS PROPERTIES

在工业化社会中，动脉僵硬度增加， 心室（LV）质量被认为是正常老化的一部分。 然而，在这方面， 在与年龄相关的变化中存在相当大的异质性， 这些变量既包括跨文化的，也包括特定的 人口 该项目的最终目标是解决 动脉硬度的改变如何影响心肌的问题 以及在结果研究中它们是否与血管功能不全有关 综合征，例如，中风 我们已展开一项试验研究， 测量心脏质量（通过核磁共振）、填充特性和 等容舒张时间（通过多普勒超声心动图），颈动脉 压力脉搏（通过扁平断层扫描）和动脉脉搏波 速度（多普勒超声）是在男性和女性谁不同， 年龄、种族、动脉压、身体成分和身体状况 条件反射状态 正如预期的那样，结果表明， 随着年龄的增长，动脉硬化导致脉搏波增加 速度 这与反射脉冲的早期返回有关 来自外周部位的波， 出现颈动脉压力脉搏峰值。 重要的是注意到 这些动脉变化大体上不能通过常规方法检测到， 肱动脉压的临床测量，并且独立于 性别差异不显著，但与运动能力呈负相关。 值得注意的是， 在身体条件良好的老年人中（大于 60岁）动脉硬度和反射波指数为 与久坐不动的同龄人相比， 与年轻人不同，尽管与年龄相关的 收缩压持续升高。 我们已经承诺， 倡议将这些研究中的许多扩展到美国黑人， 其他非西方人群中，不同的动脉模式， 压力变化随着老化而发生（在中国通过研究合同 （参见：#N01-AG-02-2118））。 长期目标包括确定 心脏结构的“标准“年龄相关变化（即， 增加左心室质量）和功能（左心室延迟 心室舒张和舒张早期充盈率降低）， 与动脉硬度的变化直接相关。 如果是这种 在这种情况下，一个长期的干预试验可能是合理的，看看是否 通过药物或生活方式改善动脉僵硬度 干预可以减弱这些与年龄相关的心脏变化， 结构和功能，并减少未来心血管疾病发病率。

In industrialized societies increases in arterial stiffness and left ventricular (LV) mass are considered part of normative aging. However, considerable heterogeneity exists in the age-associated changes in these variables both across cultures as well as within a given population. The ultimate goals of this project are to address the issue of how alterations in arterial stiffness affect the myocardium and whether in outcome studies they relate to vascular insufficiency syndromes, e.g., stroke. We have initiated a pilot study in which measurements of cardiac mass (via NMR), filling properties and isovolumic relaxation time (via Doppler echocardiography), carotid pressure pulse (via applanation tomography) and arterial pulse wave velocity (Doppler sonography) are made in men and women who differ with respect to age, race, arterial pressure, body composition, and physical conditioning status. As expected, results indicate that with increasing age arterial stiffening leads to an increase in pulse wave velocity. This is associated with an early return of reflected pulse waves from peripheral sites which produce an augmented and late occurring peak of carotid pressure pulse. It is important to note that these arterial changes are, by and large, not detected by routine clinical measures of brachial arterial pressure and are independent of gender, but vary inversely with exercise capacity. Of note, also is that in highly physically conditioned older individuals (greater than 60 yrs of age) the arterial stiffness and reflected wave indices are markedly reduced relative to their sedentary age peers and do not differ from those of younger individuals, although the age-associated increase in systolic pressure persists. We have undertaken an initiative to extend many of these studies to Black Americans and to other non-Western populations in which different patterns of arterial pressure change occurs with aging (in China via a research contract (cf. #N01-AG-02-2118)). Long term goals include determination of whether "normative"age-associated changes in cardiac structure (i.e. increasing left ventricular mass) and function (delayed left ventricular relaxation and reduced early diastolic filling rates) are directly related to changes in arterial stiffness. If such is the case, a long-term intervention trial might be justified to see whether amelioration of arterial stiffness by medication or lifestyle intervention can attenuate these age-associated changes in cardiac structure and function and reduce future cardiovascular morbidity.