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.     

Exaggerated exercise blood pressure is related to impaired endothelial vasodilator function

BACKGROUND: Persons with high normal blood pressure (BP) or mild hypertension who also have an exaggerated BP response to exercise are at risk for worsening hypertension. The mechanisms that explain this relationship are unknown. We examined the relationships of endothelial vasodilator function and of aortic stiffness with exercise BP. METHODS: Subjects were 38 men and 44 women, aged 55 to 75 years, with untreated high normal BP or mild hypertension but otherwise healthy. Exercise was performed on a treadmill. Endothelial vasodilator function was assessed as brachial artery flow-mediated vasodilation (FMD) during reactive hyperemia. Aortic stiffness was measured as pulse wave velocity (PWV). RESULTS: Among men, resting systolic BP explained 34% of the variance (P < .01) in maximal exercise systolic BP and FMD explained an additional 11% (P < .01); resting systolic BP explained 23% of the variance in maximal pulse pressure (PP) (P < .01), and FMD explained an additional 10% (P < .01). Among women, resting systolic BP was the only independent correlate of maximal systolic BP (R2 = 0.12, P < .03) and FMD correlated negatively with maximal PP (R2 = 0.12, P < .03). Among men, FMD was the only independent correlate of the difference between resting and maximal systolic BP (R2 = 0.20, P < .02). The FMD was the only independent correlate of the difference between resting and maximal PP among men (R2 = 0.17, P < .03) and among women (R2 = 0.12, P < .03). The PWV did not correlate with exercise BP responses. CONCLUSIONS: These results suggest that impaired endothelial vasodilator function may be a mechanism contributing to exercise hypertension and may also be one link between exaggerated exercise BP and worsening hypertension.     

The relationship between pulse wave velocity and pulse pressure in Chinese patients with essential hypertension.

Aortic pulse wave velocity (PWV) is a significant and independent predictor of cardiovascular disease in hypertensive subjects and in patients with end-stage renal disease, but there have been few studies on PWV in Chinese patients with essential hypertension. In this cross-sectional study, we investigated 3,156 consecutive patients (mean age: 53.7 +/- 11.58 years) of the Hypertension Division of Ruijin Hospital in Shanghai. Together with sphygmomanometric blood pressure measurements, aortic PWV was measured using a validated automatic device. PWV in patients with pulse pressure (PP) > or = 60 mmHg was significantly greater than that in patients with PP < 60 mmHg (p < 0.01). PP and PWV were positively related to age (PP: r = 0.396, p = 0.001; PWV: r = 0.531, p = 0.001). After adjustment by age and heart rate, PWV was still closely related to PP (r = 0.249, p = 0.001). At any given systolic blood pressure (SBP), PWV significantly decreased with the increase of diastolic blood pressure (DBP), whereas at any given DBP there was a significant increase of PWV with the increase of SBP. In conclusion, PWV was the major determinant of PP, and was highest in Chinese patients with isolated systolic hypertension, followed by those with systolic and diastolic hypertension, isolated diastolic hypertension, and normal blood pressure.     

Influence of sex on the relation between heart rate and aortic stiffness

BACKGROUND: Heart rate and aortic pulse wave velocity (PWV) are both cardiovascular risk factors. The aim of this study was to evaluate the influence of sex on the heart rate-PWV relationship in two populations of normotensive and hypertensive men and women. PATIENTS AND METHODS: In a first study, steady-state data describing the heart rate-PWV relationship were determined in 558 normotensive men, 308 normotensive women, 323 hypertensive men and 93 hypertensive women. In a second study, the changes in blood pressure and PWV under atrial pacing at 60, 80 and 100 beats/min were investigated in 15 men and 15 women who were either normotensive or hypertensive. RESULTS: In women in study 1, 26.8% of PWV variance in normotensive patients and 15.4% of PWV variance in hypertensive patients was explained by a multiple regression including only age and systolic blood pressure as covariates. In men in study 1, 27% of PWV variance in normotensive patients and 28.5% of PWV variance in hypertensive patients was explained by a multiple regression including age, systolic blood pressure, weight, and also heart rate, as covariates. In study 2, atrial pacing in the overall population tended to decrease mean blood pressure (P = 0.05) and increase pulse pressure (P = 0.003), with no substantial change in PWV. However, when heart rate increased, PWV tended to decrease in women and to increase in men (interaction: P = 0.07).CONCLUSION Accelerated heart rate influences PWV in both normotensive and hypertensive men and, through this mechanism, could influence cardiovascular risk. However, heart rate does not influence PWV in women.     

二尖瓣球囊扩张术对患者血浆B型利钠肽水平的影响

目的:观察二尖瓣球囊扩张术(PBMV)对二尖瓣狭窄患者血浆B型利钠肽(BNP)水平的影响。方法:检测30例成功施行PBMV的二尖瓣狭窄患者(窦性心律21例,心房颤动9例)术前、术后20 min及术后24 h的血浆BNP浓度,与8例对照者比较,并将BNP浓度与血流动力学参数作相关分析。结果:术前30例二尖瓣狭窄患者血浆BNP水平显著高于对照者(P<0．01);且与平均左心房压(r=0．441,P< 0．05)和肺动脉压(r=0．488,P<0．01)呈正相关。心房颤动患者与窦性心律患者BNP浓度无明显差异。术后20 mim及术后24 h窦性心律患者BNP浓度较术前显著下降(P均<0．05),术后24 h左心室舒张末容量(P<0．01)和每搏输出量(P<0．05)较术前相应增加,左心室舒张末压不变;术后20 min的BNP浓度变化与平均左心房压变化(r=0．696,P <0．01)及肺动脉压变化(r=0．456,P<0．05)呈正相关。术后心房颤动患者BNP浓度较术前无明显改变,左心室舒张末容量和每搏输出量相应不变,左心室舒张末压术后20 min较术前增加(P<0．01)。结论:二尖瓣狭窄患者血浆BNP浓度升高和左心房压及肺动脉压升高相关。心脏节律对球囊扩张术后血浆BNP的变化起重要作用,BNP是反映窦性心律患者球囊扩张术后左心房压及肺动脉压变化的敏感指标,但这一指标不适用于心房颤动患者。     

The relationship between high-sensitive C-reactive protein and pulse wave velocity in healthy Japanese men

Although pulse wave velocity (PWV) and high-sensitive C-reactive protein (hsCRP) are known as predictors of future cardiovascular events, their association has not been examined. The present study was conducted to evaluate their association in the general population. In 2668 Japanese men (43 +/- 10 years old), PWV was obtained by volume rendering methods, and hsCRP was determined by the latex aggregation method. PWV showed a significant correlation with logarithm of hsCRP (r = 0.06, P < 0.01). The concentration of hsCRP in the highest quartile of PWV was higher than that in the other three groups (P < 0.01). However, multiple linear regression analyses demonstrated that logarithm of hsCRP was not significantly related to PWV, independent from conventional risk factors. Calculated Framingham risk score (FRS) was higher in the highest quartiles of both hsCRP and PWV than in the other groups (P < 0.05). Thus, while increased hsCRP related to increased PWV, they may be independent predictors of atherosclerotic cardiovascular risk. A prospective study to confirm the independency of their significance in predicting future cardiovascular events and to evaluate the usefulness of the combination of both parameters to screen subjects for cardiovascular risk is necessary.     

Determinants of arterial stiffness in offspring of families with essential hypertension

BACKGROUND: Arterial stiffness may be an early marker for vascular changes associated with hypertension in young adults. We investigated whether arterial stiffness measured as augmentation index and pulse wave velocity is increased in offspring of families with essential hypertension, and whether stiffness is related to various biochemical markers. METHODS: Two groups of subjects were investigated: offspring of families with essential hypertension (mean age 39 years), and normotensive control subjects (mean age 43 years). Pulse wave analysis was used to estimate augmentation index (AIx, %). Brachial pulse wave velocity (PWV, m/sec), blood pressure, homocysteine, and creatinine were determined by standard methods. RESULTS: The offspring had significantly higher systolic, diastolic, mean arterial pressures, as well as higher homocysteine, creatinine, and glucose levels compared with normotensive control subjects. Augmentation index, but not brachial pulse wave velocity, was significantly higher in offspring (P = .010) compared with control subjects. This group difference in AIx was evident in a regression model that corrected for the known cardiovascular risk factors (P = .027). In all subjects, homocysteine associated positively with brachial PWV (r = 0.15, P < .01) and negatively with AIx (r = -0.12, P < .05). AIx also associated inversely with creatinine in the whole group (r = -0.34; P < .001) and in offspring (r = -0.38; P < .001) only. A significant positive correlation was also observed between homocysteine and creatinine in all subjects (r = 0.30; P < .001), in men (r = 0.23; P < .05) and women (r = 0.26; P < .005), respectively. CONCLUSION: These data suggests that large artery abnormalities may be present early in subjects likely to develop hypertension.     

Plasma viscosity in isolated systolic hypertension: the role of pulse pressure

Atherosclerosis is increasingly recognized as an inflammatory vascular disease, and high blood pressure (BP) has been suggested to exert a proinflammatory action. Whether plasma viscosity (PV), a major determinant of blood flow in microcirculation and a marker of systemic inflammation and cardiovascular risk, is increased in elderly subjects with isolated systolic hypertension is not known. In addition, the correlation of BP and its pulsatile component (ie, pulse pressure [PP]), with PV levels independent of the confounding effect of other cardiovascular risk factors has not been investigated. To this aim, we measured PV in 108 elderly men with never treated, uncomplicated isolated systolic hypertension, and in 60 healthy matched normotensive control subjects. The PV values were higher in hypertensive subjects than in controls (1.39+/-0.11 v 1.34+/-0.09 cP, P<.01). The PV showed a significant direct relation with both systolic BP (r=0.32) and PP (r=0.37, both P<.01), but not with diastolic BP (r=-0.03, P=.68). The PV was also directly associated with serum low-density lipoprotein cholesterol and triglycerides. In a multivariate analysis, PP was a significant predictor of PV levels when a consistent number of cardiovascular risk factors were simultaneously controlled for. In conclusion, PV is elevated in elderly subjects with isolated systolic hypertension. Systolic BP and PP appear to be major determinants of PV levels in these patients, independent of the potential proinflammatory action of traditional cardiovascular risk factors.     

Association of risk factors with increased pulse wave velocity detected by a novel method using dual-channel photoplethysmography

BACKGROUND: Pulse wave velocity (PWV) is correlated with cardiovascular risk. This study presents a new method for measuring the arterial PWV by simultaneously recording the digital volume pulse through the finger and the toe by way of dual-channel photoplethysmography (PPG). METHODS: In this study, 100 asymptomatic subjects (54 men and 46 women, 19 to 64 years of age) were enrolled. The PWV was measured both by dual-channel PPG (PWV-DVP) and by the standard method that current used applanation tonometry (PWV-AT). The developed dual-channel PPG system recorded digital volume pulse simultaneously from both the finger and toe. Time of pulse transition was measured on the time delay difference between two digital volume pulses. The PWV was calculated by dividing the distance between finger and toe by that of transit time. RESULTS: The PWV-DVP was significantly correlated with PWV-AT (r = 0.678, P < .01). With multivariate analysis controlled for age, heart rate, systolic blood pressure, and diastolic blood pressure, PWV-DVP was still significantly correlated with PWV-AT (r = 0.669, P < .01). Subjects with hypertension and dyslipidemia had significant higher PWV detected by both methods. CONCLUSION: This study showed that PWV measured with dual-channel PPG system correlated very well with that measured using the traditional method.     

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.     

Reference ranges for natriuretic peptides for diagnostic use are dependent on age, gender and heart rate

BACKGROUND: Plasma natriuretic peptide levels may be useful in the diagnosis of heart failure. The available natriuretic peptide assays differ markedly in their performance characteristics. In addition, plasma levels are influenced by a number of factors including age and gender. AIMS: The aim of this study was to describe, in a healthy population, the influence of clinical and echocardiographic parameters on three natriuretic peptide moieties. METHODS: 1360 individuals were screened for the presence of left ventricular systolic dysfunction. We identified a cohort (n=720) of men aged 45-80 years (n=417) and women aged 55-80 years (n=303). None had history of cardiovascular disease or were taking any cardiovascular medication. All had normal echocardiographic and ECG findings. B-type (BNP), N-terminal pro-B-type (N-BNP) and N-terminal pro-Atrial (N-ANP) natriuretic peptides were assayed using in-house immunoluminometric assays. RESULTS: Of the considered clinical variables, only gender and heart rate (each P<0.005) were independently associated with levels of all three natriuretic peptides. Plasma levels of N-ANP (15%), BNP (25%) and N-BNP (75%) were higher in women compared to men. An increase in heart rate of 10 bpm corresponded to a reduction of 9% in N-ANP or BNP and a 15% reduction in N-BNP. Each 10 years of age was associated with 16% and 74% increase in ANP and N-BNP levels, respectively, but no increase in plasma BNP. Left ventricular ejection fraction could be assessed in 582 (81%) subjects and correlated positively with N-ANP (r(s)=6.48x10(-3), P<0.001) and BNP (r(s)=2.4x10(-2), P<0.001) but not N-BNP (P=0.405). No parameter of diastolic function was associated with any peptide level. CONCLUSIONS: In this healthy population, plasma levels of N-ANP, BNP and N-BNP were variably influenced by clinical covariates. While all three peptides were higher in women, only N-ANP and N-BNP were influenced by age. Levels of all peptides were inversely correlated with heart rate. Using this immunoluminometric assay, plasma BNP is not influenced by age, in contrast to N-ANP and N-BNP. In constructing normal ranges for diagnostic use, covariates such as age and gender must be considered, in addition to the format of assay being used.     

Arterial stiffness is associated with minimally elevated high-sensitivity cardiac, troponin T levels in a community-dwelling population

Objectives

Arterial stiffness predicts an increased risk of future cardiovascular events, possibly via myocardial damage. Minimally elevated levels of plasma cardiac troponin T (TnT), a marker of cardiomyocyte injury, can be detected by the high-sensitivity TnT (hsTnT) assay. The current study investigated the relationship between plasma hsTnT levels and alterations in arterial stiffness in a community-based population.

Methods

We related levels of plasma hsTnT to measures of arterial stiffness (carotid–femoral pulse wave velocity [PWV], office pulse pressure [PP] and carotid–radial PWV) in 1479 participants (mean age, 62.3 years; 619 men, 860 women) from a community-based population in Beijing, China.

Results

In multiple logistic regression models, carotid–femoral PWV (OR: 1.84; 95% CI: 1.06–3.17; P = 0.028) and office PP (OR: 2.02; 95% CI: 1.31–3.11; P = 0.002) were associated with a higher likelihood of detectable hsTnT. In addition, carotid–femoral PWV (OR: 2.34; 95% CI: 1.03–5.30; P = 0.042) and office PP (OR: 2.30; 95% CI: 1.13–4.66; P = 0.022) were significantly related to elevated hsTnT levels. A subsequent subgroup analysis found that, in subjects aged 60 years and older, the associations between carotid–femoral PWV and office PP and hsTnT levels were strengthened. The associations between hsTnT with any of the arterial stiffness measures were not present in the younger subgroup (<60 years old).

Conclusions

Carotid–femoral PWV and office PP are associated with minimally elevated hsTnT levels in the elderly, indicating a relationship between central artery stiffness and subclinical myocardial damage.     

The relationship between androgens and arterial stiffness in older men

OBJECTIVES: To assess the relationship between endogenous androgen levels and arterial stiffness in older men. DESIGN: A retrospective, cross-sectional study. SETTING: A London hospital-based, clinical research unit for the elderly. PARTICIPANTS: Fifty-five men (mean age+/-standard deviation=71.1+/-8.0). INTERVENTION: Sex hormone-binding globulin (SHBG), testosterone, and dehydroepiandrosterone sulfate (DHEAS) were measured in all subjects who had a stored serum sample drawn the same day as arterial stiffness measures were performed. Free testosterone index (FTI) was calculated ((total testosterone/SHBG) x 100 (%)). The measures of arterial stiffness used were pulse wave velocity (PWV) using the Complior system and systemic arterial compliance (SAC) using the area method. MEASUREMENTS: Relationship between arterial stiffness and serum androgens. RESULTS: : FTI showed a strong positive relationship with SAC (r=0.507, P<.001) and, correspondingly, an inverse relationship with carotid-femoral (C-F) and carotid-radial (C-R) PWV (r=-0.427 and -0.402, respectively, P相似文献   

Associations between reactive oxygen species, blood pressure and arterial stiffness in black South Africans: the SABPA study

Many mechanisms, including oxidative stress, contribute to hypertension. This study investigated the possible associations between oxidative stress, blood pressure and arterial stiffness in black South Africans. Ambulatory blood pressure measurements were taken for 101 black South African men and 99 women. The stiffness indices included ambulatory arterial stiffness index (AASI) and pulse pressure (PP). Reactive oxygen species (ROS) levels (P<0.0001) were higher in the African women compared with men. ROS levels were also higher in hypertensive compared with normotensive men. The 24?h systolic blood pressure (SBP; P<0.01), 24?h diastolic blood pressure (DBP; P<0.0001) and pulse wave velocity (PWV; P<0.01) were significantly higher in African men compared with women. There were unadjusted positive associations of 24?h SBP (r=0.33; P=0.001), 24?h DBP (r=0.26; P=0.008) and 24?h PP (r=0.29; P=0.003) with ROS in African men only. A positive association between AASI and ROS existed only in hypertensive men (r=0.27; P=0.035), but became nonsignificant (B=0.0014; P=0.14) after adjustments. Adjusted, positive associations of 24?h SBP (B=0.181; P=0.018) and 24?h PP (B=0.086; P=0.050) with ROS were again only evident in African men. ROS is positively associated with SBP and PP in African men, suggesting that increased ROS levels may contribute to hypertension in this population group.     

Left ventricular ejection time: a potential determinant of pulse wave velocity in young, healthy males

OBJECTIVE: Pulse wave velocity (PWV) is a classic marker of vascular stiffness. Recent studies showed that heart rate is an important determinant of PWV. The purpose of this study was to evaluate the role of myocardial function in determining PWV under resting conditions and under adrenergic stimulation. DESIGN AND METHODS: Hemodynamic parameters were investigated under resting conditions in 102 young, healthy males and under stimulation of either beta- or alpha(2)-adrenoceptors in six young, healthy males. PWV was determined from pressure tracing over the carotid and femoral artery. Central hemodynamics were assessed by impedance cardiography and systolic time intervals. Simple (r) and multiple (beta) regression analyses were used to assess the relationships between PWV and hemodynamic parameters. RESULTS: Under resting conditions, PWV was correlated to age (beta = 0.259, P = 0.0052), diastolic blood pressure (beta = 0.279, P = 0.0072) and left ventricular ejection time (beta = -0.314, P = 0.0277). Under alpha(2)-adrenergic stimulation PWV was only correlated to diastolic blood pressure (DBP) (beta = 0.806, P = 0.0020). Under beta-adrenergic stimulation PWV was only correlated to left ventricular ejection time index (r = -0.52, P = 0.0325). CONCLUSIONS: Left ventricular ejection time may be an important determinant of pulse wave velocity under resting and adrenergic conditions in young, healthy males. Further studies are needed to evaluate this relationship in other populations including females and patients with cardiovascular disease.     

冠心病患者红细胞分布宽度与动脉硬化的相关性

目的 探讨冠心病患者红细胞分布宽度(RDW)与脉搏波传导速度(PWV)之间的相关性。方法 选择冠心病患者(冠心病组)87例,健康体检者(对照组)94例。将87例冠心病患者按RDW四分位数将患者分为:最低四分位数组(A组)28例,低四分位数组(B组)21例,高四分位数组(C组)26例,最高四分位数组(D组)12例。收集临床一般资料及心血管病危险因素,测定血脂、肌酐、白细胞、血尿酸等,测量肱-踝PWV(ba PWV)。结果 冠心病组RDW和ba PWV水平较正常对照组明显升高〔(13.1±0.8)%vs.(14.2±0.6)%,(1856±392)cm/s vs.(2029±649)cm/s,P<0.05〕;从A组到D组,ba PWV逐渐增高,分别为〔(1945.5±525.3),(1973.5±598.4),(2020.7±650.9),(2616.3±695.6)cm/s〕;D组与前3组之间的差异有统计学意义(P<0.05);相关分析显示,RDW与ba PWV(r=0.236,P<0.05)、年龄(r=0.220,P<0.05)呈正相关,多元线性逐步回归分析表明RDW是ba PWV的独立影响因素(B=602.52,P<0.01)。结论 冠心病患者的RDW与ba PWV有相关性,RDW增高患者动脉硬化程度增加。     

Atrial and brain natriuretic peptides as markers of cardiac load and volume retention in primary aldosteronism

BACKGROUND: Atrial and brain natriuretic peptides (ANP and BNP, respectively) are cardiac hormones with natriuretic and vasodilator actions. The present study was carried out to determine the natriuretic peptide that is closely related to cardiac load and volume retention in patients with primary aldosteronism (PA). METHODS: We examined 11 patients with PA due to aldosterone-producing adrenal adenoma before and after surgical resection. Plasma levels of ANP and BNP were measured by specific immunoradiometric assays, and total blood volume was determined by a plasma tracer method with (131)I-human albumin. RESULTS: Plasma levels of ANP and BNP were elevated in the PA patients compared with normotensive control subjects (P < .01), and the elevated ANP and BNP levels were reduced (P < .01) after adenoma resection. When analyzed with the pre- and postoperative data, a significant relationship was observed between mean blood pressure and plasma levels of ANP (r = 0.64, P < .01) and BNP (r = 0.58, P < .01). The BNP was significantly correlated with the SV1 + RV5 voltage (r = 0.65, P < .01) and with total blood volume (r = 0.57, P < .01), but this was not the case for ANP. CONCLUSION: The present results suggest that the plasma level of BNP is more closely related to cardiac load or volume status than ANP is, in patients with PA due to adrenal adenoma.     

Pulse pressure and aortic pulse wave are markers of cardiovascular risk in hypertensive populations

BACKGROUND: Pulse pressure (PP) and aortic pulse wave velocity (PWV) are significant markers of cardiovascular risk, but a similar role for central wave reflections has never been investigated. PROCEDURES: To determine the factors influencing PP, PWV, and carotid wave reflections, a cohort of 1087 patients with essential hypertension either treated or untreated was studied cross-sectionally. Atherosclerotic alterations (AA) were defined on the basis of clinical events and PWV evaluated from an automatic device. The carotid amplification index (CAI), a quantitative estimation of the magnitude of central wave reflections, was measured noninvasively from pulse wave analysis using radial and carotid aplanation tonometry. RESULTS: In the overall population, age and mean arterial pressure represented 30.4%, 32.3%, and 5.6% of the variance of, respectively PP, PWV, and CAI. For the latter, body weight and heart rate represented 22.9% of variability. On the basis of logistic regression, AA were associated, in addition to age, plasma creatinine and HDL cholesterol levels, and tobacco consumption to three mechanical factors, increased PP, increased PWV, and low diastolic blood pressure, but not by CAI (adjusted odds ratio: 1.00; 95% confidence intervals: 0.99-1.01). CONCLUSION: In cross-sectional hypertensive populations, PP and PWV, but not CAI, are significantly and independently associated with cardiovascular amplications.     

Diastolic blood pressure is an important determinant of augmentation index and pulse wave velocity in young,healthy males

Pulse wave velocity (PWV) and augmentation index are widely used measures of arterial stiffness. The purpose of this study was to evaluate the role of blood pressure as a determinant of both indices independent of potentially confounding factors including gender, age and cardiovascular disorders. A total of 77 young, healthy subjects were investigated under resting conditions. Augmentation index was derived by pulse wave analysis using carotid applanation tonometry. PWV was determined from pressure tracing over the carotid and femoral artery. The relations between stiffness markers and haemodynamic parameters were analysed by simple (r) and multiple (beta) regression analysis. Using simple regression analysis, augmentation index was correlated to age (r=0.292, P=0.0105), diastolic blood pressure (DBP, r=0.483, P<0.0001), mean arterial blood pressure (MAP, r=0.381, P=0.0007), pulse pressure (r=-0.414, P=0.0002) and total peripheral resistance (r=0.266, P=0.0204). After multiple regression analysis, augmentation index remained significantly correlated only to DBP (beta=0.347, P=0.0051). Using simple regression analysis, PWV was correlated to age (r=0.304, P=0.0067), systolic blood pressure (r=0.280, P=0.0129). DBP (r=0.455, P<0.0001), MAP (r=0.446, P&<0.0001) and heart rate (r=0.348, P=0.0018). After multiple regression analysis, PWV remained correlated only to age (beta=0.218, P=0.0422) and DBP (beta=0.4105, P=0.0316). In summary, DBP is an important determinant of augmentation index and PWV in young, healthy males. Further studies are needed to characterize the impact of blood pressure on arterial stiffness in other populations including females and older subjects.     

Anemia as a factor that elevates plasma brain natriuretic peptide concentration in apparently healthy subjects

Plasma brain natriuretic peptide (BNP) is widely used as a biomarker of heart failure (HF); however, its concentration is often found to be high even in apparently healthy subjects and little is known about which factors contribute to physiological change in plasma BNP concentration in subjects without HF. We examined the effects of gender, age, and anemia on plasma BNP concentration in apparently healthy subjects. The study population consisted of 1036 healthy subjects who underwent an annual health examination at their company in 2005. There were 874 women, ranging in age from 30 to 63 years (mean, 41 years). Plasma BNP concentration was abnormal (> 18.4 pg/mL) in 292 subjects. The incidence was significantly higher in women than in men (31% versus 14%, P < 0.01). Mean plasma BNP concentration was higher in women than in men. The difference in plasma BNP concentration was associated with the difference in blood hemoglobin and age. Logarithmically transformed BNP concentration correlated inversely with blood hemoglobin (r = -0.30, P < 0.01 for all; r = -0.21, P < 0.01 for women; r = -0.20, P < 0.01 for men). By multiple regression analysis, logarithmically transformed BNP concentration correlated with hemoglobin, age, and gender. In conclusion, anemia is likely a critical determinant that elevates plasma BNP concentration in apparently healthy subjects.