Division of Cardiology, Johns Hopkins University, Baltimore, Md 21287, USA.
Hypertension. 2010 Feb;55(2):319-26. doi: 10.1161/HYPERTENSIONAHA.109.141275. Epub 2010 Jan 11.
Arterial stiffness predicts cardiovascular events beyond traditional risk factors. However, the relationship with aging of novel noninvasive measures of aortic function by MRI and their interrelationship with established markers of vascular stiffness remain unclear and currently limit their potential impact. Our aim was to compare age-related changes of central measures of aortic function with carotid distensibility, global carotid-femoral pulse wave velocity, and wave reflections. We determined aortic strain, distensibility, and aortic arch pulse wave velocity by MRI, carotid distensibility by ultrasound, and carotid-femoral pulse wave velocity by tonometry in 111 asymptomatic subjects (54 men, age range: 20 to 84 years). Central pressures were used to calculate aortic distensibility. Peripheral and central pulse pressure, augmentation index, and carotid-femoral pulse wave velocity increased with age, but aortic strain and aortic arch PWV were most closely and specifically related to aging. Ascending aortic (AA) strain and distensibility decreased, respectively, by 5.3+/-0.5% (R(2)=0.54, P<0.0001) and 13.6+/-1 kPa(-1)x10(-3) (R(2)=0.62, P<0.0001), and aortic arch pulse wave velocity increased by 1.6+/-0.13 m/sec (R(2)=0.60, P<0.0001) for each decade of age after adjustment for gender, body size, and heart rate. We demonstrate in this study a dramatic decrease in AA distensibility before the fifth decade of life in individuals with diverse prevalence of risk factors free of overt cardiovascular disease. In particular, compared with other measures of aortic function, the best markers of subclinical large artery stiffening, were AA distensibility in younger and aortic arch pulse wave velocity in older individuals.
动脉僵硬度可预测传统危险因素以外的心血管事件。然而，通过 MRI 测量新型非侵入性主动脉功能的与年龄相关的变化及其与血管僵硬度的既定标志物的相互关系尚不清楚，目前限制了其潜在影响。我们的目的是比较中心主动脉功能的与年龄相关的变化与颈动脉扩张度、整体颈动脉-股脉搏波速度和波反射之间的关系。我们通过 MRI 确定了主动脉应变、扩张度和主动脉弓脉搏波速度，通过超声确定了颈动脉扩张度，通过张力测定法确定了颈动脉-股脉搏波速度，共纳入 111 名无症状受试者（54 名男性，年龄范围：20 岁至 84 岁）。使用中心血压计算主动脉扩张度。外周和中心脉搏压、增强指数和颈动脉-股脉搏波速度随年龄增长而增加，但主动脉应变和主动脉弓脉搏波速度与年龄最密切和最具特异性相关。升主动脉（AA）应变和扩张度分别降低 5.3+/-0.5%（R(2)=0.54，P<0.0001）和 13.6+/-1 kPa(-1)x10(-3)（R(2)=0.62，P<0.0001），主动脉弓脉搏波速度增加 1.6+/-0.13 m/sec（R(2)=0.60，P<0.0001），每十年增加一次，调整性别、身体大小和心率后。我们在这项研究中表明，在没有明显心血管疾病的个体中，AA 扩张度在生命的第五个十年之前就会出现显著下降，且在不同的危险因素流行率下，AA 扩张度在年轻人中是反映大动脉僵硬度亚临床变化的最佳标志物，而在老年人中则是主动脉弓脉搏波速度。
