【正文】 ondon 2020 20% BSP 300% APP 4x s 80 40 80 40 mmHg mmHg The pulsatile ponent, PP Determinants: 1. pattern of left ventricular ejection 2. cushioning capacity of aorta 3. the timing and intensity of wave reflections. arterial stiffness amp。 ALLCAUSE MORTALITY IN 1980 HYPERTENSIVES 0 5 10 15 20 Followup (years) Survival Low PWV tertile Medium PWV tertile High PWV tertile KaplanMeier P Laurent et al., Hypertension 2020 PWV amp。99:2434 ≤ PWV ≤ m/s ≤ PWV ≤ m/s （ PWV）較慢，反射波落在升主動脈壓力波的舒張期（上圖）。 Determinants of Arterial Stiffness pressure wall structure: vascular smooth muscle(VSM) cells, collagen fibers, and ground substance. Collagen greatly modifies arterial rigidity and the transit of wave reflections. Neurohumoral factors(RAS systems), may modulate collagen accumulation. Chemical modifications of collagen, such as breakdown, crosslinking, or glycation, result in marked changes in stiffness. 3. The function of endothelium Changes in VSM tone are modulated by nitric oxide (NO) and vasoconstrictive (norepinephrine, angiotensin, endothelin) pounds, which mainly depend on the function of endothelium. Amplitude of Earlier Wave Reflections mainly based on the geometry, number, structure, and function of smaller muscular arteries and arterioles which serve as major reflection sites ? or remodeling of small arteries and arterioles ? and branching angles of arterioles ? of the microenvironment (in particular sodium and other cations), ? endotheliummediated vasodilation, ? in matrix position of small arteries and arterioles, ? mediated alterations of vasomotor tone, arising from smooth muscle or endothelial cells. 動脈硬度與心血管危險 動脈硬度 ↑ 反射波強度 ↑ amp。 心力衰竭 舒張壓 ↓ 脈壓 ↑ 搏動性壓力和流量 ↑ 腦與腎 的微循環(huán)損害 ↑ 0 0 動脈硬化如何改變大腦與腎的循環(huán)？ 腦、腎 其它器官 ?引自 O’Rourke MF, Safar ME. Hypertension 2020。Pulse Wave Analysis A simple method to assess arterial stiffness and distensibility. Widely used. Noninvasive and reproducible. Simultaneous assessment shows modest correlation (r=). Yasmin Brown MJ. QJM. 1999。 113:233562 Reduction in LV mass with therapy in 2 years Parameters β = β = Aortic AIx 28 37 PP amplification 41 53 Radial AIx 45 59 Aortic augmented pressure 70 93 Aortic SBP 270 360 Brachial DBP 543 726 Brachial SBP 966 1294 Number of subjects required with α (twosided) = Hashimoto J, O’Rourke MF et al. Presented at AHA HBPR Council 2020, San Antonio, TX Effects of physiological phenomena on the arterial stiffness ? Aging: the dominant process altering vascular stiffness, ? wave reflections, and PP ? Physical fitness ? Heart rate ? Blood pressure ? Geic background: a potential factor of importance The change of blood pressure with age in China BPsruvey in 1990 (n=950,000)6070809010011012013014015015 20 25 30 35 40 45 50 55 60 65 70 75 80Age(yr)BP(mmHg)menwomenbothThe change of PP with age in China BP Survey in 1990 (n=950,000)354045505560657015 25 35 45 55 65 75Age(yr)Pulse Pressure(mmHg)menwomenbothNichols WW, O’Rourke MF. McDonald’s Blood Flow in Arteries. 5th ed. London。 BODY MASS INDEX PWV is related to BMI (Adapted from TotoMoukouo et al., 1986) 19 21