Prognostic value of systolic and diastolic blood pressure in treated hypertensive men

BACKGROUND: The aim of this study was to assess the cardiovascular risk in hypertensive subjects according to systolic blood pressure (SBP) and diastolic blood pressure (DBP) levels. METHODS: The study sample consisted of 4714 hypertensive men, treated by their physician, who had a standard health checkup at the d'Investigations Préventives et Cliniques Center, Paris, France, between 1972 and 1988. Cardiovascular disease (CVD) and coronary heart disease (CHD) mortality were assessed for a mean period of 14 years. RESULTS: Among treated subjects, 85.5% presented uncontrolled values for SBP (> or = 40 mm Hg) and/or DBP (> or = 90 mm Hg). After adjustment for age and associated risk factors, these subjects presented an increased risk for CVD mortality (risk ratio [RR], 1.66; 95% confidence interval [CI], 1.04-2.64) and for CHD mortality (RR, 2.35; 95% CI, 1.03-5.35) compared with controlled subjects. After adjustment for age, associated risk factors, and DBP, and compared with subjects with SBP under 140 mm Hg, the RR for CVD mortality was 1.81 (95% CI, 1.04-3.13) in subjects with SBP between 140 and 160 mm Hg and 1.94 (95% CI, 1.10-3.43) in subjects with SBP over 160 mm Hg. By contrast, after adjustment for SBP levels, CVD risk was not associated with DBP. Compared with subjects with DBP under 90 mm Hg, RR for CVD mortality was 1.17 (95% CI, 0.80-1.70) in subjects with DBP between 90 and 99 mm Hg and 1.03 (95% CI, 0.67-1.56) in subjects with DBP over 100 mm Hg. Similar results were observed for CHD mortality. CONCLUSIONS: In hypertensive men treated in clinical practice, SBP is a good predictor of CVD and CHD risk. Diastolic blood pressure, which remains the main criterion used by most physicians to determine drug efficacy, appears to be of little value in determining cardiovascular risk. Evaluation of risk in treated individuals should take SBP rather than DBP values into account.     

Determinants of arterial stiffness in Greek and French hypertensive men

The aim of the present study was to assess the main determinants of arterial stiffness in Greek and French middle-aged, hypertensive men, by using pulse wave velocity (PWV) measurements, which is an established method of quantification of arterial stiffness. The study was performed in 83 consecutive Greek and 79 consecutive French untreated male hypertensive outpatients aged 45-65 years. French subjects were examined in Paris at the "Centre d'Investigations Préventives et Cliniques" (the IPC Center). Greek patients were examined in Athens at the hypertension outpatient clinic in Sotiria Hospital (University of Athens). In both Greek and French hypertensive subjects, aortic stiffness was determined by the same parameters: age, blood pressure and heart rate (HR) explained approximately 40% of the aortic PWV variations, whereas lipids, triglycerides and tobacco smoking were not significant associated with aortic stiffness. After multivariate adjustments, Greek hypertensives had higher aortic stiffness as compared to the French patients by 1.2 m/s (approximately 10%); p < 0.001. Greek hypertensive subjects had also a higher body weight, waist, HR and prevalence of smoking. However, among all these factors only HR had a significant effect on PWV. Also after adjustment for HR, the difference in PWV between the two populations persisted. In conclusion, in two different populations, stiffness seems to be regulated by the same major factors. The higher aortic stiffness found in Greek hypertensives may be explained by the presence of other non-evaluated risk factors and/or patient selection differences.     

Impaired arterial elasticity in young patients with white-coat hypertension

BACKGROUND: Conflict still exists over whether patients with white-coat hypertension are at increased risk of developing target organ damage compared with normotensive individuals. METHODS: We studied vascular distensibility in 117 young-to-middle age patients with white-coat hypertension, 174 patients with sustained hypertension, and 51 normotensive controls. To obtain a measure of compliance, a model was used that divides the total systemic compliance into large artery (C1) and small artery (C2) compliance. With this aim, radial arterial pulse waves were recorded with a tonometer sensor array by means of an HDI CR2000 device (Eagan, Minnesota, USA). Moreover, pulse wave velocity and the augmentation index were measured using the Specaway DAT system (St Pauls, Sydney, Australia). RESULTS: Patients with sustained hypertension had a greater body mass index than patients with white-coat hypertension (P=0.04) or the normotensive individuals (P=0.01). C1 and C2 were decreased in the two hypertensive groups as compared with those in the normotensive group (P=0.0002 and 0.03, respectively, versus sustained hypertension; P=0.00007 and 0.0004, respectively, versus white-coat hypertension). Pulse wave velocity and aortic augmentation index were increased in the white-coat hypertension patients compared with the normotensive individuals (P=0.02 and 0.004, respectively). Aortic augmentation index (P=0.008) but not pulse wave velocity was increased in the sustained hypertensive patients compared with that in the normotensive individuals. All indexes of arterial distensibility were similar in the two hypertensive groups. CONCLUSIONS: Indexes of arterial distensibility are impaired in the white-coat hypertensive group and similar to those in the sustained hypertensive group, indicating that early changes in the arterial wall can occur in white-coat hypertension. This may account for the higher risk of stroke that has been described in this condition.     

Increased pulse pressure amplification in treated hypertensive subjects with metabolic syndrome

BACKGROUND: Brachial pulse pressure (PP) is physiologically higher than central PP. This PP amplification, which protects the heart from increased afterload, is related to the progressive increase of arterial stiffness along the vascular tree and subsequent changes in pressure wave reflections. The PP amplification increases with high heart rate (HR), which is observed in subjects with metabolic syndrome (MS). The objective of this study was to investigate whether PP amplification is affected by MS and is related to cardiovascular (CV) risk. METHODS: In 613 subjects treated for hypertension (41% with MS) pulse wave analysis was used to investigate carotid blood pressure (BP), pressure wave reflections from carotid augmentation index (AI), and arterial stiffness from aortic pulse wave velocity (PWV). The CV risk was estimated from standard Framingham equations. RESULTS: Pulse pressure amplification, HR, and PWV, but not AI, were increased in subjects with MS compared to control subjects without MS with the same age, gender, and mean arterial pressure. The difference in PP amplification between the two groups disappeared after adjustment for both HR and PWV. The AI was the main predictor of PP amplification, representing 28% and 19% of its total variance in subjects without and with MS, respectively. The CV risk for coronary, but not for cerebral, mortality was related to PP amplification. CONCLUSIONS: Although PWV is increased in treated hypertensive subjects with MS, compared to control, PP amplification is increased due to the effect of increased HR and attenuated pressure wave reflections. The observed relation of increased PP amplification with organ-specific CV risk needs further investigation.     

Expert consensus document on the measurement of aortic stiffness in daily practice using carotid-femoral pulse wave velocity

Stiffness of elastic arteries like the aorta predicts cardiovascular risk. By directly reflecting arterial stiffness, having the best predictive value for cardiovascular outcome and the ease of its measurement, carotid-femoral pulse wave velocity is now considered the gold standard for arterial stiffness assessment in daily practice. Many different measurement procedures have been proposed. Therefore, standardization of its measurement is urgently needed, particularly regarding the distance measurement. This consensus document advises on the measurement procedures in general and provides arguments for the use of 80% of the direct carotid-femoral distance as the most accurate distance estimate. It also advises the use of 10?m/s as new cut-off value for carotid-femoral pulse wave velocity.     

Differences in pulse pressure day variability between the brachial artery and the aorta in healthy subjects

Objectives

To search for: (i) potential differences in the within-subject pulse pressure (PP) day time variability between the brachial artery and aorta; (ii) the presence of substantial day time variation in the aortic-to-brachial (AtB) PP disparity.

Background

Brachial blood pressure (BP) variability is a risk factor, but also a source of inaccuracy for the assessment of BP-related cardiovascular risk. PP differs substantially in simultaneous measurements at the brachial artery and the aorta; this is of clinical importance regarding accurate cardiovascular risk assessment and reduction strategies. Whether the brachial and the aortic PP time variability is similar, and whether the AtB PP disparity varies during the day is not known.

Methods

In 13 healthy volunteers hourly assessment of brachial and aortic PP was performed (8:00-19:00) under controlled conditions at home.

Results

Aortic PP day variability was consistently and significantly lower than brachial PP (assessed by: standard deviation, variance and time rate variation index, p < 0.05 for all). Individual AtB PP difference (brachial - aortic PP, mmHg) varied substantially within all the 13 subjects; a significant variation during the day in the AtB PP amplification (defined as brachial/aortic PP) was evident (p = 0.006).

Conclusions

By taking into account both time and arterial space, substantial physiological differences in PP variability between the brachial artery and the aorta were observed. These novel findings suggest that non-invasive 24-h aortic ambulatory BP monitoring is warranted in order to significantly improve CV risk assessment and reduction strategies. This possibility must be tested in future clinical studies.     

Total arterial compliance,estimated by a novel method,is better related to left ventricular mass compared to aortic pulse wave velocity: The SAFAR study

Aim: The investigation of the association between total arterial compliance (C_T)—estimated by a novel technique—with left ventricular mass (LVM) and hypertrophy (LVH). Our hypothesis was that C_T may be better related to LVM compared to the gold-standard regional aortic stiffness. Within the frame of the ongoing cross-sectional study “SAFAR,” 226 subjects with established hypertension or with suspected hypertension underwent blood pressure (BP) assessment, carotid-to-femoral pulse wave velocity (cf-PWV), and echocardiographic measurement of LVM. LVM index (LVMI) was calculated by the ratio of LVM to body surface area. C_T was estimated by a previously proposed and validated formula: C_T = 36.7 /cf-PWV² [ml/mmHg]. LVMI was related to age (r = 0.207, p = 0.002), systolic BP (r = 0.248, p < 0.001), diastolic BP (r = 0.139, p = 0.04), mean BP (r = 0.212, p = 0.002), pulse pressure (r = 0.212, p = 0.002), heart rate (r = ?0.172, p = 0.011), cf-PWV (r = 0.268, p < 0.001), and C_T (r = ?0.317, p < 0.001). The highest correlation was observed for C_T that was significantly stronger than the respective correlation of cf-PWV (p < 0.001). In multivariate analysis, C_T was a stronger determinant, compared to cf-PWV, of LVMI and LVH. It remains to be further explored whether C_T has also a superior prognostic value beyond and above local or regional (segmental) estimates of pulse wave velocity.