Takayasu's arteritis: a cause of prolonged arterial stiffness

OBJECTIVES: Cardiovascular disease is a major cause of mortality and morbidity in patients with Takayasu's arteritis (TA). Increased arterial stiffness is an independent risk factor and predictor of cardiovascular mortality in a variety of diseases. Pulse wave velocity (PWV) and the augmentation index (AI) are used as clinical measurements of arterial stiffness. METHODS: Data are presented from 10 patients with TA and 11 normal controls obtained between 2000 and 2004. Arterial compliance was assessed non-invasively by measurement of PWV, using the Complior system, and calculation of the aortic AI. RESULTS: TA patients (mean age 40.8+/-13.2 yr) were compared with a control group of healthy women from a parallel study (mean age 32.3+/-5.5 yr). The mean carotid-femoral PWV (PWV-CF) was higher in TA patients (P = 0.03). In addition, both aortic AI derived from the radial artery (P = 0.002) and carotid AI (P = 0.03) were higher in TA patients compared with controls. PWV-CF did not correlate with CRP (r = - 0.23, P = 0.23) or ESR (r = - 0.19, P = 0.27). Similar results were obtained for the correlation of carotid-radial PWV with CRP (r = 0.15, P = 0.32) and ESR (r = 0.33, P = 0.14). CONCLUSIONS: Our data show that TA is associated with elevated arterial stiffness in the central aorta, which may persist when the disease is quiescent. These data suggest that PWV represents a means by which cardiovascular risk can be detected and monitored in TA, and highlights the importance of effective management of cardiovascular risk factors in these patients.     

Increased pulse wave velocity and shortened pulse wave propagation time in young patients with rheumatoid arthritis

BACKGROUND: Rheumatoid arthritis (RA) is a systemic immune and inflammatory disease associated with excess cardiovascular morbidity and mortality. Pulse wave velocity (PWV) is an index of arterial stiffness and a marker of cardiovascular events. OBJECTIVE: To investigate arterial stiffness using carotid-femoral (aortic) PWV measurements in young patients with RA. PATIENTS AND METHODS: Eight patients (aged 21 to 34 years, seven women, mean RA duration 13.8+/-12.6 months) with RA according to the criteria of the American College of Rheumatology, and eight age- and sex-matched control subjects (aged 22 to 34 years, seven women) were recruited. Aortic PWV was determined using an automatic device, the Complior (Complior Colson, France), which allowed on-line pulse wave recording and automatic calculation of PWV. RESULTS: The carotid-femoral PWV, systolic blood pressure and heart rate were higher in young patients with RA than in sex- and age-matched control subjects (P=0.03, P=0.02 and P=0.002, respectively). In the young patients with RA, pulse wave propagation time between measurement sites was significantly shorter than in the control group (P=0.02). There were no significant differences in the sex, age, body mass index, waist to hip ratio, diastolic blood pressure, mean blood pressure or pulse pressure between the two groups (P=1.00, P=0.71, P=0.20, P=0.66, P=0.55, P=0.07 and P=0.11, respectively). CONCLUSION: The carotid-femoral PWV is increased and pulse wave propagation time is decreased in young patients with RA. Measurements of carotid-femoral PWV may provide a simple and noninvasive technique for identifying patients at increased risk of vascular disease.     

脉压及尿微量白蛋白/肌酐与老年单纯收缩期高血压患者脉搏波传导速度

目的:探讨脉压及尿微量白蛋白/肌酐(UACR)与老年单纯收缩期高血压患者主动脉脉搏波传导速度(PWV)的关系.方法:老年单纯收缩期高血压(ISH)患者354例,进行血压、生化指标及UACR测定,应用自动脉搏波传导速度分析仪检测颈-股动脉PWV.将患者分为脉压>60 mmHg(1 mmHg=0.133 kPa)和≤60 mmHg两部分进行分析.按照UACR三分位切点值分三组,UACR<10.34 mg/g组、UACR(10.34~25.60)mg/g组、UACR>25.60 mg/g组,每组118例.结果:①脉压>60 mmHg患者的颈-股动脉PWV比脉压≤60 mmHg患者高(P<0.01),差异有统计学意义.②随UACR值由低到高,三组患者颈-股动脉PWV值逐渐增高,差异有统计学意义(P相似文献   

Vascular stiffness is related to superoxide generation in the vessel wall

OBJECTIVES: Oxidative stress causes endothelial dysfunction and plays a major role in the pathogenesis of cardiovascular disease. Increased vascular stiffness is an intermediate phenotype in the development of cardiovascular disease. We hypothesized that vascular stiffness is partially determined by oxidative stress. METHODS: We examined 163 participants out of whom 80 had coronary artery disease. Vascular stiffness was assessed by pulse wave analysis, pulse wave velocity and measurement of aortic compliance by cardiac MRI. Circulating markers of oxidative stress and vascular superoxide generation in saphenous vein were measured. RESULTS: After adjustment for age, sex, BMI, heart rate, blood pressure and lipids only carotid-femoral pulse wave velocity and aortic compliance were different between patients and control group. Aortic compliance was reduced (11.4 +/- 6.3 vs. 13.9 +/- 7.3 ml x 10(-3) per mmHg; P = 0.035) and vascular superoxide generation increased (1.01 +/- 0.45 vs. 0.76 +/- 0.44 nmol/mg per min; P = 0.035) in patients with coronary artery disease compared with those without. In a multiple stepwise regression analysis, aortic compliance was determined by age (P < 0.001) and vascular superoxide production (P = 0.033). CYBA C242T and NOS3 G894T polymorphisms had additive effects on vascular superoxide generation (P = 0.026) and xanthine oxidase activity was increased in patients with CAD (P = 0.043). Genetic factors (P = 0.033) and xanthine oxidase activity (P < 0.001) were also related to aortic compliance. CONCLUSION: By measuring vascular superoxide generation and aortic compliance using cardiac MRI, we demonstrated a functional relationship between oxidative stress and vascular stiffness. Patients identified with high levels of vascular stiffness are most likely to benefit from strategies to reduce vascular oxidative stress.     

Relationship between albumin excretion rate and aortic stiffness in untreated essential hypertensive patients

OBJECTIVES: To evaluate, in a group of nondiabetic essential hypertensive patients with normal renal function, the relationship between albumin excretion rate (AER) and carotid-femoral pulse wave velocity (PWV), as an index of aortic stiffness. DESIGN: Cross-sectional study. SETTING: Outpatient hypertension clinic. SUBJECTS: Seventy patients with mild-to-moderate essential hypertension, aged 42 +/- 8 years, never pharmacologically treated. All subjects underwent routine laboratory tests, 24-h ambulatory blood pressure (BP) monitoring, measurement of carotid-femoral PWV, by means of a computerized method, and AER. RESULTS: Microalbuminuric patients (AER > or = 20 microg min(-1); n = 19), when compared with normoalbuminuric subjects, showed more elevated 24-h BP (136/88 +/- 10/10 vs. 128/83 +/- 7/6 mmHg; P < 0.001 and P = 0.013, for systolic and diastolic BP respectively) and higher values of carotid-femoral PWV (10.4 +/- 2 m s(-1) vs. 9.2 +/- 1.3; P = 0.006). This latter difference remained statistically significant, even after correction by ancova for 24-h systolic and diastolic BP, and body mass index (BMI, P = 0.016). Univariate regression analysis disclosed a tight correlation between AER and carotid-femoral PWV (r = 0.42; P = 0.0003). This association was confirmed in a multiple regression model (beta = 0.35; P = 0.009) in which, as independent variables, besides PWV, 24-h BP, age, serum glucose values, smoking status, gender and BMI, were added. CONCLUSIONS: Our results seem to confirm that microalbuminuria may represent the early renal manifestation of a widespread vascular dysfunction, and therefore it is an integrated marker of cardiovascular risk.     

Low-grade inflammation and hypoadiponectinaemia have an additive detrimental effect on aortic stiffness in essential hypertensive patients.

AIMS: In this study, we investigated the combined effect of increased high-sensitivity C-reactive protein (hs-C-reactive protein) and hypoadiponectinaemia on aortic stiffness in essential hypertensive subjects. METHODS AND RESULTS: A total of 267 untreated patients with stage I-II essential hypertension underwent ambulatory BP and carotid-femoral pulse wave velocity (c-f PWV) evaluation. The distributions of hs-C-reactive protein and adiponectin were split by the median (1.3 mg/L and 7.8 microg/mL, respectively) and accordingly subjects were stratified into those with high and low values. Patients with high (n = 134) compared with those with low hs-C-reactive protein (n = 133) values exhibited greater c-f PWV levels (by 0.8 m/s, P < 0.0001), whereas patients with low (n = 133) compared with those with high (n = 134) adiponectin levels had higher c-f PWV (by 0.9 m/s, P < 0.0001). Stepwise regression analysis revealed that age, 24 h systolic BP, hs-C-reactive protein and adiponectin were independent predictors of arterial stiffness. In patients with low hs-C-reactive protein, hypoadiponectinaemia (n = 46) compared with high adiponectin (n = 87) was accompanied by increased c-f PWV (by 0.8 m/s, P < 0.0001). Similarly in patients with high hs-C-reactive protein, hypoadiponectinaemia (n = 84) compared with high adiponectin (n = 50) was related to heightened c-f PWV (by 0.7 m/s, P = 0.008). CONCLUSION: In essential hypertension, pronounced low-grade inflammation in conjunction with hypoadiponectinaemia exerts an additive detrimental effect on aortic stiffness, accelerating the vascular ageing process.     

高血压病患者动态血压与动脉顺应性的相关性研究

目的:探讨高血压病患者动脉顺应性的变化,及其与动态血压监测(ABPM)各指标间的相互关系。方法:对262例高血压病患者和104例正常人进行动态血压监测(ABPM)和脉搏波速度(PWV)测定。结果:高血压组的颈动脉-桡动脉(G-R)PWV、颈动脉-股动脉(C-F)PWV,24 h、白昼及夜间平均血压,平均脉压,心率,血压负荷均显著高于正常对照组(P<0.05~<0.01)。C-F PWV及C-R PWV与24 h、白昼及夜间平均血压,心率,血压负荷均呈显著正相关(r=0.108~0.406,P<0.05~<0.001)。C-F PWV比C-R PWV与平均收缩压和收缩压负荷的相关性更强。C-F PWV与动态脉压、年龄显著正相关(r=0.205~0.406,P<0.001)。结论:动脉顺应性减退是高血压的重要改变,大动脉顺应性与动态脉压、收缩压和年龄的关系更为密切。     

The relationship between aortic augmentation index and pulse wave velocity: an invasive study

OBJECTIVES : The aortic augmentation index (AI) and aortic pulse wave velocity (PWV) are known to be indicators of arterial stiffness. However, it is not clear whether aortic AI and PWV reflect aortic stiffness in similar ways. We investigated the relationship between aortic AI and PWV by measuring them directly using a catheter technique. DESIGN AND METHODS: Forty-one patients, aged 34-79 years, were studied during diagnostic cardiac catheterization. Aortic pressures were measured using a catheter-tip manometer at two points, one in the ascending aorta and one 40 cm distally in the descending aorta. Aortic AI was defined as the difference between early and late pressure peaks divided by the pulse pressure of the ascending aorta. Aortic PWV was calculated as the distance between the two measuring sites divided by the transit time. We also examined the effects of vasodilatation on AI and PWV by the intra-aortic administration of nitroglycerin in 15 patients. RESULTS: AI was significantly related to age, systolic aortic pressure, heart rate, left ventricular ejection time, and height. Aortic PWV showed an association only with age and systolic aortic pressure. There was no significant relationship between aortic AI and PWV (r = 0.28, NS). Nitroglycerin also produced different effects on aortic AI and PWV: aortic AI was significantly decreased (-0.17, P < 0.01) after nitroglycerin, but PWV remained unchanged (+0.4 m/s, NS). CONCLUSIONS: Aortic AI and PWV cannot be used interchangeably as an index of arterial stiffness. AI may not be a true indicator of arterial stiffness, but an index of wave reflection including PWV.     

亚甲基四氢叶酸还原酶基因C677T多态性与原发性高血压患者动脉顺应性的关系

目的研究亚甲基四氢叶酸还原酶基因C677T多态性与原发性高血压及动脉顺应性的关系。方法对695例原发性高血压患者和509例年龄匹配的正常对照者采用聚合酶链反应和限制片长多态性分析方法进行基因多态性分析,电泳判断基因型及测序,并测定颈动脉—桡动脉脉搏波速度和颈动脉—股动脉脉搏波速度。结果高血压组TT基因型频率和T等位基因频率显著高于正常对照组(26.5%比20.6%及48.7%比42.4%,P=0.015和0.002)。T等位基因携带者的颈动脉—股动脉脉搏波速度显著高于CC基因型者(P<0.05),高血压组颈动脉—桡动脉脉搏波速度在T等位基因携带者也显著高于CC基因型者(P=0.001)。携带T等位基因的高血压患者颈动脉—股动脉脉搏波速度及非单纯收缩期高血压患者颈动脉—桡动脉脉搏波速度均显著高于CC基因型者(P<0.05)。结论亚甲基四氢叶酸还原酶基因C677T多态性可能与原发性高血压发病危险性增加有关,并且677T等位基因可能是高血压动脉硬化的遗传因素。     

Pulse wave velocity as endpoint in large-scale intervention trial. The Complior study. Scientific, Quality Control, Coordination and Investigation Committees of the Complior Study

OBJECTIVE: To evaluate the ability of an antihypertensive therapy to improve arterial stiffness as assessed by aortic pulse wave velocity (PWV) in a large population of hypertensive patients. SETTING: Sixty-nine healthcare centres, private and institutional (19 countries). PATIENTS: Subjects aged 18-79 years, with essential hypertension. A total of 2,187 patients were enrolled; 1,703 (52% male) completed the study: mean age = 50 +/- 12 years; mean baseline systolic/diastolic blood pressure (S/D BP) = 158 +/- 15/98 +/- 7 mmHg; mean baseline carotid-femoral PWV = 11.6 +/- 2.4 m/s. INTERVENTIONS: Patients were treated for 6 months, starting with perindopril (angiotensin converting enzyme (ACE) inhibitor) 4 mg once daily (OD), increased to 8 mg OD, and combined to diuretic (indapamide 2.5 mg OD) if BP was uncontrolled (> 140/90 mmHg). RESULTS: It was feasible to measure carotid-femoral PWV using the automatic device Complior at inclusion, 2 and 6 months, along with conventional BP assessments in a population of 1,703 patients. Significant decreases (P < 0.001) in BP (systolic: -23.7 +/- 16.8, diastolic: -14.6 +/- 10 mmHg), and carotid-femoral PWV (-1.1 +/- 1.4 m/s) were obtained at 2 and 6 months. CONCLUSIONS: The Complior Study is the first study to show the feasibility of a large-scale intervention trial using PWV as the endpoint in hypertensive patients. Adequate results may be obtained using an automatic device and rigorous criteria for assessment. A long-term controlled intervention study is needed to confirm the results of the present uncontrolled trial.     

Increased arterial stiffness in remote Indigenous Australians with high risk of cardiovascular disease

OBJECTIVE: To assess central and peripheral arterial stiffness in Indigenous and European Australians with and without type 2 diabetes using applanation tonometry to obtain the augmentation index (AI) and pulse wave velocity (PWV). METHODS: AI was assessed in 162 Indigenous Australians (60 with type 2 diabetes) participating in a population-based study and 121 Australians of European ancestry (38 with diabetes) of similar age and sex. PWV was assessed in a subgroup: n = 62 indigenous, n = 118 European participants. RESULTS: The indigenous group had higher AI than the European group [mean (SD) 32 (12) versus 24 (12)%, P < 0.0001] and carotid-femoral PWV [8.4 (1.8) versus 7.1 (2.2) ms(-1), P < 0.0001]. There were no significant differences between groups regarding blood pressure and total cholesterol; however, indigenous individuals had higher fasting glucose, insulin, haemoglobin A1c, triglycerides, waist circumference (despite lower body mass index), and a higher prevalence of cigarette smoking. Fifty-five per cent of the variance in AI was explained on multiple regression analysis by age, sex, indigenous participant, heart rate, mean arterial pressure, height, triglycerides and waist circumference. Age, indigenous participant, heart rate, mean arterial pressure and antihypertensive medication explained 56% of the variance in PWV. Variables of the metabolic syndrome and smoking, C-reactive protein (CRP), homocysteine and heart rate clustered with indigenous status on factor analysis. CONCLUSIONS: Indigenous Australians have higher indices of peripheral and central arterial stiffness than European Australians of similar age and sex. Factor analysis revealed that metabolic syndrome variables, smoking, CRP, homocysteine and heart rate clustered with 'indigenous participant' and may explain increased arterial stiffness in this group.     

Validity of pulse pressure and augmentation index as surrogate measures of arterial stiffness during beta-adrenergic stimulation

OBJECTIVE: Increased arterial stiffness is a determinant of cardiovascular mortality. Pulse wave velocity (PWV) is a direct measure of arterial stiffness. Aortic augmentation index (AI) and pulse pressure (PP) are surrogate measures of arterial stiffness. Both PWV, AI and PP increase with cardiovascular risk factors. The aim of this study was to test the validity of AI and PP as surrogate measures of arterial stiffness compared with PWV, during beta-adrenergic stimulation with Isoprenaline (Iso). DESIGN AND METHODS: A total of 41 healthy volunteers entered a randomized, double-blind, placebo-controlled, cross-over study. In random order, subjects were given intravenous infusion in equal volume of Iso 8 microg/kg per min (dissolved in glucose 5%) and placebo (glucose 5%). A wash-out period of 25 min was observed between the infusions. Measurements included blood pressure (BP), heart rate (HR), PWV, and AI. PWV were determined using complior (Complior, Artech-Medical, Paris, France). AI and aortic PP were obtained from pulse wave analysis of radial applanation tonometry, using transfer function (SphygmoCor Windows software). RESULTS: Baseline AI increased (P < 0.05) with aging, a lower height and a larger diastolic BP (DBP). Iso increased (P < 0.0001) HR, brachial SBP, brachial and aortic PP as compared with placebo. In contrast, Iso decreased (P < 0.05) AI, brachial DBP, peripheral PWV, but not aortic PWV. Decrease of AI induced by Iso was not related to PWV. In stepwise multiple regression changes in HR, brachial SBP and DBP were independent determinants of AI response to Iso (r = 0.78, P < 0.0001). CONCLUSIONS: Our findings show that AI and PP fail as surrogate measures of arterial stiffness during beta-adrenergic stimulation.     

Acute effects of oral melatonin administration on arterial distensibility, as determined by carotid-femoral pulse wave velocity, in healthy young men

The aim of the present study was to investigate the effects of melatonin administration on arterial distensibility by using carotid-femoral (aortic) pulse wave velocity (PWV) measurements in healthy young men. Ten men were studied (five men in the melatonin group and five men in the placebo group) by physicians. Carotid-femoral (aortic) PWV, blood pressure and plasma melatonin were measured in the supine position before and 60 min after oral administration of melatonin or placebo. Although carotid-femoral (aortic) PWV, systolic blood pressure and mean blood pressure were decreased, pulse wave propagation time and plasma melatonin levels were increased at 60 min after oral melatonin (1 mg) administration (P=0.04, P=0.04, P=0.04, P=0.04 and P=0.04, respectively). No significant differences were found between all parameters in the placebo group (P>0.05). In conclusion, these findings indicate that melatonin administration, compared with placebo, decreased carotid-femoral PWV and systolic blood pressure in the supine position in healthy young men. Administration of melatonin may have an inhibitory effect on sympathetic tone.     

Indices of pulse wave analysis are better predictors of left ventricular mass reduction than cuff pressure

BACKGROUND: Studies have required large numbers of patients to associate regression of left ventricular (LV) mass with a decrease in brachial cuff blood pressure (BP) in the treatment of hypertension. Hence, we prospectively examined potential superiority of pulse wave analysis over conventional BP measurement in predicting treatment-induced LV mass reduction. METHODS: Forty-six untreated patients (mean age, 56 +/- 7 years) with hypertension received standard medical treatment based on international guidelines. Echocardiography and measurements of various LV load indices were made before and after 1 year of treatment. RESULTS: Antihypertensive treatment significantly (P < .05) reduced LV load, manifest by a decrease in measured brachial BP, estimated aortic BP, carotid-femoral pulse wave velocity (PWV(cf)), aortic augmentation index (AI(a)), aortic augmented pressure (AugP), and radial augmentation index (AI(r)). These changes were accompanied by significant reduction in LV mass index (LVMI) and improvements in systolic ejection fraction and diastolic early-to-atrial ratio of transmitral flow velocities. The treatment-induced LVMI change was not correlated with changes in brachial BP or PWV(cf), but was closely correlated with factors influenced by wave reflection - changes in AI(a), AI(r), AugP, and aorta-to-arm pulse pressure amplification. On multivariate analysis, AI(a) change was the strongest determinant of LVMI change, independent of brachial BP and PWV(cf) changes (beta = 0.51, P < .001). Estimated subject numbers required for predicting a significant LVMI reduction were far less when wave reflection-related factors were used rather than conventional bracial BP. CONCLUSIONS: These results suggest that reduction in wave reflection is an important therapeutic strategy for reducing LV mass, which can be predicted with modest subject numbers.     

Aortic stiffness, inflammation, denutrition and prognosis in the oldest people

Observational studies have shown that some of the classic CV risk factors, namely hypertension or hypercholesterolemia, become nebulous, or even act in the reverse direction, in the oldest people. We investigated whether in the elderly, increased aortic stiffness was associated with higher mortality risk, before and after adjustments on common geriatric confounders. In a cohort of 331 (86 men) subjects aged >70 years (mean age (± s.d.): 85 ± 7 years), aortic stiffness was assessed by carotid-femoral pulse wave velocity (PWV). Classical CV risk factors were determined simultaneously, in association with inflammation and denutrition parameters. One hundred and ten subjects died during a 2-year follow-up period. In crude analysis, a positive non-significant trend was observed between PWV and mortality risk. Multivariate Cox regression analysis showed that five parameters entered the prediction model: two were positively related to mortality risk, PWV (P = 0.008) and orosomucoide (P = 0.045), and three were related negatively, total cholesterol (P = 0.006), albumin (P = 0.026) and body weight (P = 0.035). Interaction analysis revealed that the effect of PWV on mortality was increased in the presence of renal dysfunction and increased inflammation. In conclusion, although marginally significant in crude analysis, PWV is a powerful determinant of prognosis in the oldest people taking into account inflammation and denutrition.     

Influence of the metabolic syndrome on aortic stiffness in never treated hypertensive patients

BACKGROUND AND AIM: Metabolic syndrome (MS) carries an increased risk for cardiovascular events and there is a growing awareness that large artery stiffening is a powerful predictor of cardiovascular morbidity and mortality. Little is known about the relationship of MS with aortic stiffness. The aim of our study was to analyze, in patients with essential hypertension, the influence of MS, defined according to the criteria proposed by the Third Report of the National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (NCEP-ATP III), on carotid-femoral pulse wave velocity (PWV), a measure of aortic stiffness. METHODS: Ninety-three untreated essential hypertensives, aged between 23 and 61 years, without diabetes mellitus, were studied. All subjects underwent routine blood chemistry, oral glucose tolerance test with glucose and insulin determinations, albumin excretion rate (AER) measurement, 24-h ambulatory blood pressure monitoring, and measurement of carotid-femoral PWV, by means of a computerized method. RESULTS: Patients with MS (n = 28) showed higher age-adjusted carotid-femoral PWV (10.1 +/- 1.4 vs 9.3 +/- 1.4 m/s; p = 0.01) when compared to subjects without MS. This difference held after controlling for gender and for 24-h mean blood pressure (MBP) (p = 0.02) and lost its statistical significance after further adjustment for AER. In a multiple regression model, excluding the individual components of MS, in which metabolic syndrome was added along with age, gender, smoking habit, LDL cholesterol, HOMA index, 24-h MBP and 24-h heart rate, MS remained independently associated with carotid-femoral PWV (beta = 0.29; p = 0.002). The statistical significance of this association disappeared after the inclusion into this model of AER. CONCLUSIONS: Metabolic syndrome is associated with an increased aortic stiffness. Main explanatory factors of this association are age, systolic blood pressure and albumin excretion rate.     

高血压大鼠模型主动脉僵硬度的超声多普勒评价

目的 建立一种大鼠模型超声多普勒颈-股脉搏波传播速度（PWV）准确测量方法，将其应用于自发性高血压大鼠（SHR）及其对照组中，验证该方法能否区分SHR已知增加的动脉僵硬度（AS），并探讨其应用价值。 方法 纳入雄性SHR大鼠12只，周龄、体质量相当的健康对照组Wistar Kyoto（WKY）大鼠12只。大鼠颈-股PWV的测量采用超声多普勒法完成。 结果 SHR与WKY大鼠在周龄、体长、体质量、测量期间的心率等指标对比的差异均无统计学意义。SHR大鼠的收缩压、舒张压显著高于WKY大鼠[（176 ± 4)mmHg vs (121 ± 5) mmHg，(123 ± 4) mmHg vs (85 ± 5) mmHg，均P < 0.01]；SHR大鼠的颈-股PWV测值与对照组相比显著增高[（6.5 ± 1.0)m/s vs (4.5 ± 0.9) m/s, P < 0.01]；Bland-Altman一致性检验显示两组大鼠的颈-股PWV测值在观察者间具有良好的重复性。 结论 超声多普勒颈-股PWV测量方法能够精确测量SHR大鼠模型脉搏波传播时间和距离，藉以评价其AS。基于超声多普勒的PWV测量是一种评价大鼠模型AS的可靠方法。     

Isolated systolic hypertension is characterized by increased aortic stiffness and endothelial dysfunction

Isolated systolic hypertension is associated with increased cardiovascular risk. It is thought to result from large artery stiffening, which is determined by structural components within the vasculature but also by functional factors including NO and endothelin-1. We hypothesized that endothelial dysfunction would account for increased arterial stiffness in patients with isolated systolic hypertension. The aim of this study was to investigate the relationship between endothelial function and arterial stiffness in these patients along with control subjects. We studied 113 subjects: 35 patients with isolated systolic hypertension (mean age+/-SD: 68+/-6 years), 30 age-matched control subjects (65+/-5 years), and 48 young control subjects (37+/-9 years). Aortic pulse wave velocity (PWV) was derived by sequential carotid/femoral waveform recordings. Conduit artery endothelial function was determined by flow-mediated dilatation. Aortic PWV was higher (9.65+/-2.56 m/s versus 8.26+/-0.85 m/s; P=0.009), and flow-mediated dilatation was lower (2.67+/-1.64% versus 4.79+/-3.1%; P=0.03) in patients with isolated systolic hypertension compared with age-matched control subjects. Similarly, aortic PWV was also higher, and flow-mediated dilatation lower, in older versus young control subjects (8.26+/-0.85 m/s versus 7.09+/-1.01 m/s and 4.79+/-3.1% versus 6.94+/-2.7%; P=0.004 for both). Overall, aortic PWV correlated inversely with flow-mediated dilatation (r=-0.3; P=0.001), which remained significant after adjustment for confounding factors (P=0.01). Patients with isolated systolic hypertension have higher aortic PWV and decreased endothelial function compared with age-matched control subjects. Our results suggest that endothelial function contributes significantly to increased arterial stiffness in patients with isolated systolic hypertension and with age.     

Assessment of vascular aging and atherosclerosis in hypertensive subjects: second derivative of photoplethysmogram versus pulse wave velocity

The pulse wave velocity (PWV) and the photoplethysmogram (PTG) are noninvasive methods for evaluating the pulse wave. The PWV has been associated with age and arterial hypertension, and an index of the second derivative of PTG (SDPTG) is correlated with age and other risk factors for atherosclerosis. The aim of this study was to compare SDPTG and PWV concerning the influencing factors of vascular compliance, including age and atherosclerosis, in a large hypertensive population. We studied consecutively 524 essential hypertensives, 140 with atherosclerotic alterations (AA), defined on the basis of clinical events including coronary heart disease, peripheral vascular disease, stroke, and abdominal aorta aneurysm. The PWV carotid-femoral was measured by a Complior device and the SDPTG was recorded by Fukuda FCP-3166. The augmentation index (AUI) of PTG was defined as the ratio of the late systolic peak to that of the early systolic peak in the pulse. The SDPTG consists of an a,b,c, and d wave in systole and an e wave in diastole; an SDPTG aging index (AI) was calculated as (b-c-d-e)/a. The patients with AA presented a higher PWV (14.9 +/- 4 m/sec v 12.4 +/- 2 m/sec, P < .001), PTG AUI (0.322 +/- 0.16 v 0.252 +/-0.09, P < .001), and SDPTG AI (-0.093 +/- 0.03 v -0.271 +/- 0.018, P < .001). However, in patients 60 years of age, only PWV remained higher in those with AA, whereas in patients >60 yr, both PWV and SDPTG AI remained higher in those with AA. The PWV was independently influenced by age, systolic blood pressure, glucose, AA, and plasma creatinine, whereas the PTG AUI was influenced by age and systolic pressure and the SDPTG AI by age and AA. In a logistic regression model for the presence of AA, including age, plasma creatinine, smoking, and diastolic BP, PWV was a significant independent determinant of AA, whereas SDPTG-AI weakly entered into the model. This study provides evidence that the aortic PWV reflects better than the SDPTG the modifications of the arterial compliance related to age, blood pressure, and atherosclerosis. However, the SDPTG AI may be useful for evaluation of vascular aging in hypertensives.     

Left ventricular diastolic dysfunction is accompanied by increased aortic stiffness in the early stages of essential hypertension: a TDI approach

OBJECTIVE: To investigate the inter-relationship between aortic stiffness and left ventricular (LV) diastolic function in subjects with newly diagnosed uncomplicated essential hypertension. METHODS: We studied 106 consecutive newly diagnosed subjects (aged 51 years, 80 males) with stage I-II essential hypertension, and 50 normotensives matched for age, sex and body mass index. LV diastolic function was estimated by pulsed tissue Doppler imaging (TDI) echocardiography, averaging diastolic mitral annular velocity measurements (Emav, Amav, Emav/Amav ratio) from four separate sites (basal septal, lateral, anterior, and inferior LV wall). Moreover, aortic stiffness was evaluated by non-invasive carotid-femoral pulse wave velocity (c-f PWV) measurement. RESULTS: Hypertensives compared with normotensives exhibited greater LV mass index and Amav (110 versus 95 g/m and 10 versus 8.8 cm/s, respectively, P < 0.001 for both cases), and greater c-f PWV (8.47 versus 7.48 m/s, P < 0.03), as well as lower Emav and Emav/Amav values, (8.4 versus 10 cm/s and 0.82 versus 1.15, respectively, P < 0.001 for both cases). In the group of hypertensives, a univariate analysis revealed that c-f PWV was negatively associated with Emav (r = -0.305, P = 0.005), as well as with Emav/Amav ratio (r = -0.437, P < 0.001). Moreover, a multivariate analysis showed that the TDI-derived Emav/Amav ratio was significantly associated with age (P = 0.001), relative wall thickness (P = 0.006) and c-f PWV (P = 0.03), while the conventional Doppler-derived E/A ratio was significantly associated only with age (P = 0.001). CONCLUSIONS: TDI-detected LV diastolic dysfunction is accompanied by increased aortic stiffness in newly diagnosed essential hypertension, suggesting that there may be a common pathophysiological pathway linking these two entities.