Relation of pulse pressure and blood pressure reduction to the incidence of myocardial infarction

Stepwise increase in arterial stiffness corresponding with the stages of chronic kidney disease

BACKGROUND

Patients with end-stage renal disease on maintenance dialysis therapy have a high prevalence of cardiovascular risk factors and cardiovascular disease (CVD). A similar finding is noted in patients with chronic kidney disease (CKD). The important contributors are premature and accelerated atherosclerosis and vascular calcification. We assessed the severity of arterial stiffness in 102 patients with CKD by using pulse wave velocity (PWV) and sought to identify associated risk factors.

METHODS

PWV was measured by calculating the distance traveled by the flow wave and divided by the time delay. Correlations between PWV and traditional cardiovascular risk factors, estimated glomerular filtration rate (GFR) per 1.73 m2 , blood pressure (BP), and pulse pressure (PP) were analyzed.

RESULTS

PWV values in patients with CKD stages 1 to 2 and the age-matched control group were similar. There was a significant trend for a stepwise increase in PWV corresponding to advance in CKD stage (P < 0.0001). Univariate linear regression analysis showed that age, prior CVD, diabetes, hypertension, any high risk, estimated GFR per 1.73 m2 , systolic BP, and PP correlated with PWV. In the multivariate model, decreased estimated GFR per 1.73 m2 and increased systolic BP were independently associated with increased PWV in patients with CKD (model R 2 = 0.539; P < 0.0001).

CONCLUSION

This is the first study to show a greater PWV in patients with more advanced CKD from stages 1 to 5. Estimated GFR per 1.73 m2 and systolic BP were the major clinical determinants of arterial stiffness in patients with CKD independent of conventional risk factors for CVD.

Importance of arterial pulse pressure as a predictor of coronary heart disease risk in PROCAM

AIMS

To investigate pulse pressure (PP) as an independent predictor of coronary heart disease (CHD) risk.

METHODS AND RESULTS

On the basis of a 10-year follow-up of 5389 men aged 35-65 at recruitment into PROCAM, we used a proportional hazards model to calculate the effect of systolic blood pressure (SBP), diastolic blood pressure (DBP), and PP on CHD risk after correcting for age, high-density lipoprotein cholesterol, LDL cholesterol, triglycerides, smoking, diabetes, and family history of premature CHD. Increases of 10 mmHg in DBP, SBP, and PP were associated with an increased CHD hazard ratio (HR) of approximately 10%. When the group was divided into the age groups <50, 50-59, and >59 years, this relationship was seen in the age group 50-59 years for DBP, SBP, and PP and in men aged > or =60 for PP only (25% increase in HR). Overall, CHD risk in men with PP > or =70 mmHg was more three times that of men with PP <50 mmHg. This increased risk was not apparent at age <50 years, was greatest at age >60 years, and was also present in men who were normotensive at recruitment (SBP < or =160 mmHg, DBP < or =95 mmHg).

CONCLUSION

In older European men, increased PP is an important independent determinant of coronary risk, even among those initially considered normotensive.

Pulse pressure correlates with leukoaraiosis in Alzheimer disease

The relation between pulse pressure (PP) and Alzheimer disease (AD) remains unclear. We performed this study to investigate the relation between PP and AD and the impact of PP to impair cognitive performance on this relationship. It is a cross-sectional study from the Neurology Memory Clinic of Chungnam National University Hospital and five senior welfare centers in the city of Taejon, Korea. A cohort of 75 patients with AD and 117 control subjects were enrolled for the study. PP was significantly higher whereas mean arterial pressure (MAP) was lower in patients with AD than those of control subjects. Elevated serum total cholesterol (TC) level was significantly associated with both PP and MAP in control subjects as well as patients with AD. We found a significant relationship between PP and cerebral white matter changes (WMCs) in AD. PP changes correlate with leukoaraiosis in AD.

Long-term prognostic impact of repeated measurements over 1 year of pulse pressure and systolic blood pressure in the elderly

Systolic blood pressure (SBP) and pulse pressure (PP) have been identified in western industrialized countries as major predictors of cardiovascular events in the elderly on the basis of measurements taken at a single visit. Considering the wide variability of blood pressure (BP) in older people, this study set out to assess the prognostic significance of measurements of SBP and PP taken over several months according to a monitoring scheme mimicking routine care. A total of 444 Italian general practitioners enrolled a cohort of 3858 unselected elderly outpatients and followed them up for 10 years. BP was recorded at recruitment, 1 week later and at quarterly visits during the first year. The average BP of these six visits was used to define the patient's BP status. During the 10-year follow-up, 1561 participants died, 709 from cardiovascular diseases. Proportional hazard regression analysis, adjusted for all main prognostic factors including antihypertensive treatment, showed that for each 10-mmHg increment in SBP and PP there were, respectively, 5 and 9% increases in risk for total mortality (TM) and 9 and 13% increases in risk for cardiovascular mortality (CVM) (all P < 0.01). However, including both SBP and PP in the model, only PP showed an independent, significant relationship with TM and CVM. In conclusion, prognostic information based on repeated measurements of PP is stronger than that given by SBP and consequently should be recommended in the definition of cardiovascular risk in the elderly.

Pulse Pressure and Cardiovascular Events in Postmenopausal Women With Coronary Heart Disease

BACKGROUND

Pulse pressure (PP) has been shown to predict risk for cardiovascular events in men; however, this association has not been well established in women. Hormone replacement therapy may improve arterial compliance, but findings from cross-sectional and prospective studies report inconsistent results. We sought to examine the relationship between PP and risk for cardiovascular events, and to determine the effect of hormone therapy on PP in postmenopausal women with coronary heart disease (CHD).

METHODS AND RESULTS

A total of 2,763 postmenopausal women (mean age, 66 +/- 7 years [+/- SD]) with CHD in the Heart and Estrogen/Progestin Replacement Study, a randomized, placebo-controlled, secondary CHD prevention trial of estrogen plus progestin, were followed up on average for 4.1 years. BP was measured at baseline and annually. Mean baseline PP was 62 +/- 16 mm Hg. There were 361 myocardial infarctions (MIs) or CHD deaths, 265 hospitalizations for congestive heart failure (CHF), and 215 strokes or transient ischemic attacks (TIAs). Women in the highest quartile of PP at baseline had a 47% increase in risk for MI or CHD death and more than a twofold increase in risk for stroke and TIA events or hospitalization for CHF (p < 0.01 for each outcome). After adjustment for other cardiovascular risk factors and mean arterial pressure, PP remained significantly associated with incident stroke or TIA events (odds ratio, 1.25; p = 0.02) and hospitalizations for CHF (odds ratio, 1.31; p < 0.01) but not with MI or CHD death. After adjustment for diastolic BP, systolic BP was similarly associated with stroke or TIA (odds ratio, 1.30; p < 0.01) and hospitalized CHF (odds ratio, 1.30; p < 0.01) and was also weakly associated with risk for MI and CHD death (odds ratio, 1.18; p = 0.02). Mean PP was 1- to 2-mm Hg higher in women randomized to hormone replacement therapy vs those receiving placebo (p < 0.01).

CONCLUSIONS

PP had predictive value for CHF and stroke or TIA, but not MI or CHD death in this cohort of postmenopausal women with CHD. Use of hormone replacement therapy produced a small, statistically significant increase in PP. Further research is necessary to determine the clinical utility of PP as a potential therapeutic target.

Systolic and diastolic blood pressure lowering as determinants of cardiovascular outcome

Based on individual patient data, we performed a quantitative overview of trials in hypertension to investigate to what extent lowering of systolic blood pressure (SBP) and diastolic blood pressure (DBP) contributed to cardiovascular prevention. We selected trials that tested active antihypertensive drugs against placebo or no treatment. Our analyses included 12,903 young (30 to 49 years of age) patients randomized in 3 trials and 14,324 old (60 to 79 years of age) and 1209 very old (> or =80 years of age) patients enrolled in 8 trials. Antihypertensive treatment reduced SBP/DBP by 8.3/4.6 mm Hg in young patients, by 10.7/4.2 mm Hg in old patients, and by 9.4/3.2 mm Hg in very old patients, respectively, resulting in ratios of DBP to SBP lowering of 0.55, 0.39, and 0.32, respectively (P=0.004 for trend with age). In spite of the differential lowering of SBP and DBP, antihypertensive treatment reduced the risk of all cardiovascular events, stroke and myocardial infarction in the 3 age strata to a similar extent. Absolute benefit increased with age and with lower ratio of DBP to SBP lowering. Furthermore, in patients with a larger-than-median reduction in SBP, active treatment consistently reduced the risk of all outcomes irrespective of the decrease in DBP or the achieved DBP. These findings remained consistent if the achieved DBP averaged <70 mm Hg. In conclusion, our overview suggests that antihypertensive drug treatment improves outcome mainly through lowering of SBP.

Aortic pressure augmentation predicts adverse cardiovascular events in patients with established coronary artery disease

Pulse pressure (PP), a marker of arterial stiffness, predicts cardiovascular risk. We aimed to determine whether augmentation pressure (AP) derived from the aortic pressure waveform predicts major adverse cardiovascular events (MACE) and death independently of PP in patients with established coronary artery disease (CAD). We prospectively followed-up 297 males undergoing coronary angiography for 1186+/-424 days. Ascending aortic pressure tracings obtained during catheterization were used to calculate AP (difference between the second and the first systolic peak). Augmentation index (AIx) was defined as AP as a percentage of PP. We evaluated whether AP and AIx can predict the risk of MACE (unstable angina, acute myocardial infarction, coronary revascularization, stroke, or death) and death using Cox regression. All models evaluating AP included PP to assess whether AP adds to the information already provided by PP. Both AP and AIx significantly predicted MACE. The hazard ratio (HR) per 10 mm Hg increase in AP was 1.20 (95% confidence interval [CI], 1.08 to 1.34; P<0.001); the HR for each 10% increase in AIx was 1.28 (95% CI, 1.11 to 1.48; P=0.004). After adjusting for other univariate predictors of MACE, age, and other potential confounders, AP remained a significant predictor of MACE (HR per 10 mm Hg increase=1.19; 95% CI, 1.06 to 1.34; P=0.002), as did AIx (adjusted HR, 1.28; 95% CI, 1.09 to 1.50; P=0.003). AP was a significant predictor of death (HR per 10 mm Hg increase=1.18; 95% CI, 1.02 to 1.39; P=0.03). Higher AIx was associated with a trend toward increased mortality (HR=1.22; 95% CI, 0.98 to 1.52; P=0.056). Aortic AP predicts adverse outcomes in patients with CAD independently of PP and other risk markers.

Is High Pulse Pressure a Marker of Preclinical Cardiovascular Disease?

This study tests the hypothesis that high brachial pulse pressure might constitute preclinical cardiovascular disease, rather than a risk factor. We studied 1250 subjects (472 nonobese normotensive [<135/80 mm Hg] and 778 untreated hypertensive). Central pulse pressure was estimated from brachial pulse pressure and age and divided by stroke volume (PP/SV). Brachial pulse pressure was considered high when >63 mm Hg, and peripheral resistance high when >90th percentile of normal distribution. Among hypertensive subjects, 34% had high resistance; among them, 33% had high brachial pulse pressure, as opposed to 147 of 516 patients (28.5%) with normal resistance ( P =not significant). After adjusting for age, sex, race, body mass index, heart rate, and center, left ventricular (LV) internal dimension and mass were lower with high resistance, and higher when brachial pulse pressure was high. PP/SV was 36% higher with high resistance than with normal resistance, and higher when brachial pulse pressure was high (all P <0.0001). Factorial analysis demonstrated that associations of high brachial pulse pressure with both higher PP/SV and LV mass were independent of other pressure components. Thus, because of these associations, our hypothesis is that in hypertension, pulse pressure may be considered as a marker of preclinical cardiovascular disease, similar to LV mass and PP/SV, rather than a cardiovascular risk factor.

Neural activity of the cardiac baroreflex decreases with age in normotensive and hypertensive subjects

OBJECTIVES

Baroreflex control of the heart rate is impaired in hypertensive subjects and decreases with age. The decrease in cardiac baroreflex sensitivity (BRS) is often ascribed to decreased distension of the pressure-sensing arterial wall segments. However, alterations in the sensing and processing of neural signals may be involved as well.

DESIGN

Conventionally, both vessel wall stiffness and the sensing and neural processing of the baroreflex are incorporated in the measure of pressure-derived BRS. We introduce stretch-derived BRS, which only considers the sensing and neural components of the baroreflex.

METHODS

To determine stretch-derived BRS in a non-invasive manner, we measured the spontaneously occurring low-frequency variations (range, 0.06-0.12 Hz) in the carotid artery diameter and the corresponding R-R interval fluctuations, and determined the associated transfer function. The stretch-derived BRS in a group of age-matched (age range, 25-72 years) normotensive (n = 20) and hypertensive (n = 21) subjects was compared.

RESULTS

In both subject groups the stretch-derived BRS decreased significantly with age. Moreover, the stretch-derived BRS of both groups was only different below 50 years of age.

CONCLUSIONS

The analysis of low-frequency fluctuations in the carotid artery diameter demonstrates that aging as well as hypertension are associated with impaired neural control of the baroreflex. Beyond 50 years of age the effect of hypertension cannot be distinguished from the effect of aging.

Pharmacotherapy and blood pressure control in elderly hypertensives in a primary care setting in Bahrain

BACKGROUND AND AIMS

Antihypertensive treatment in the elderly has important beneficial effects in terms of reduced cardiovascular morbidity and mortality. The aim of this study was to determine, in elderly hypertensives, the adherence of primary care physicians to World Health Organization/International Society of Hypertension (WHO/ISH) guidelines for the drug management of hypertension and extent of blood pressure (BP) control.

METHODS

A multicentric therapeutic audit of medical records of elderly hypertensives was performed in nine primary care health centers in the Kingdom of Bahrain.

RESULTS

In elderly hypertensives (> or =60 years), the WHO/ISH-1999 recommended BP targets of <140/<90 mmHg and BP<130/85 mmHg were achieved in 11.1% of elderly hypertensives and 4.1% of elderly diabetic hypertensives, respectively. Antihypertensive combination therapy was used in approximately half of the elderly. No significant difference in BP was found in elderly hypertensives treated either with monotherapy or combination therapy. As regards mono- and overall drug utilization, beta-blockers were the most frequently prescribed drugs in hypertensives, and angiotensin-converting enzyme (ACE) inhibitors in diabetic hypertensives. Diuretics and calcium channel blockers, the preferred antihypertensives for the elderly, were less often prescribed, particularly in patients with isolated systolic hypertension.

CONCLUSIONS

Approximately one out of 9 elderly hypertensives and one out of 24 diabetic hypertensives achieved optimal BP control. Although preference for antihypertensives was markedly influenced by comorbidity with diabetes, tailoring of drug therapy was suboptimal and did not adhere to the recommended guidelines in elderly hypertensives. Efforts to improve the drug management of hypertension at primary care level, particularly in the elderly, are required.

The impact of body mass index on pulse pressure in obesity

OBJECTIVE

Pulse pressure, a marker of arterial vascular properties, has been linked to cardiovascular diseases and complications. This study examined the impact of excess body mass and cardiovascular disease risk factors on pulse pressure (PP).

DESIGN

Cross-sectional and prospective study.

METHODS

Baseline data consist of 219 obese African Americans, with mean +/- SD age of 46.8 +/- 10.9 years enrolled in a diet and exercise program of weight reduction. A non-invasive monitoring device was used to acquire 24 hourly ambulatory blood pressures. Pulse pressure was calculated as the difference between the average 24-h systolic and diastolic blood pressure and studied as a continuous variable and according to quartiles. The cross-sectional association of pulse pressure with body mass index (BMI) was examined using multivariate linear regression and proportional odds models that controlled for cardiovascular disease risk factors. In addition, we examined prospectively, in 36 participants, the effect of weight loss on pulse pressure, using the Wilcoxon signed ranked test.

RESULTS

At baseline, a 5 kg/m2 increase in BMI was independently associated with a 35% risk [relative risk (RR) = 1.35, confidence interval (CI) = 1.10-1.65, P < 0.01] in the general study population and 19% (RR = 1.19, CI = 1.07-1.56, P = 0.04) in obese normotensives for increasing PP by one quartile after adjustment for other significant variables. After 3 months of diet and exercise intervention, BMI decreased by an average of 10.6% (P < 0.01) and resulted in an 8.8% (P < 0.01) reduction in PP.

CONCLUSIONS

In the context of obesity, increasing BMI is independently associated with decreasing arterial compliance, as reflected in PP. This association highlights the potential value to cardiovascular health of any reduction in body weight in obese individuals.

Wide pulse pressure is an independent predictor of cardiovascular mortality in Puerto Rican men

BACKGROUND AND AIM

Emerging evidence suggests that pulse pressure is an independent predictor of risk for cardiovascular mortality. New studies in diverse populations are needed to further establish the applicability of this finding. Thus, the purpose of this study is to examine the relationship between pulse pressure and cardiovascular mortality in a cohort of Puerto Rican men after 12 years of follow-up.

METHODS AND RESULTS

The Puerto Rico Heart Health Program is a study of coronary disease risk factors in men aged 35-79 years at baseline who had an initial examination during the years 1962-1965. It was attended by 9824 subjects representing 80% of the total age-specific male residents in 4 rural and 3 urban areas of Puerto Rico. Cardiovascular risk factors including systolic and diastolic blood pressures were monitored prospectively. This study includes 9106 men free of overt CHD at baseline who were stratified by quartiles of pulse pressure in mmHg: quartile 1, <or=38, quartile 2, 39-46; quartile 3, 47-56; and quartile 4, >or=57. The odds ratio of cardiovascular mortality was calculated using logistic regression analysis. After adjusting for age, education, smoking status, hypercholesterolemic status, physical activity, diabetic status and mean arterial pressure, we found that those in the highest quartile of pulse pressure (pulse pressure>=57) had significantly higher cardiovascular mortality than those in the lowest quartile (reference group) (OR=1.38 95% CI=1.01-1.88).

CONCLUSION

Our findings showed that a wide pulse pressure is independently associated with cardiovascular mortality in this group of Puerto Rican men.

Fatigue and plaque rupture in myocardial infarction

Plaque rupture plays a role in the majority of acute coronary syndromes. Rupture has been associated with stress concentrations, which are affected by tissue properties and anatomy. In this study rupture was not approached as an acute syndrome, but rather as the culmination of a chronic injury or fatigue process. The aim of our study was to investigate the impact of anatomy, tissue properties, and blood pressure on a fatigue mechanism. Incremental crack propagation was dynamically simulated based on evolving stress distributions. Stresses were resolved by a finite element solver, using vessel stiffness properties derived from in vivo data. Plaque fatigue crack growth per pressure pulse was estimated using an adapted Paris-relation. It was demonstrated that cracks begin at the lumen wall at areas of stress concentration, depending on the shape of the lumen, thickness of the fibrous cap and stiffness of the plaque components. Mean or pulse pressure did not affect initiation location. Cracks extended radially and grew at a rate that was highly dependent on both mean and pulse pressure and on lipid stiffness. Rupture rate depended on blood pressure and lipid stiffness. It was concluded that a fatigue mechanism in a pulsatile cardiovascular pressure environment reconciles clinical evidence of acute plaque rupture at seemingly low stress levels, and it could provide a framework for developing strategies to create a biomechanically benign environment which is least conducive to plaque rupture.

Age-related increase of pulse pressure and plasminogen activator inhibitor-1 I/D gene polymorphism in essential hypertension

BACKGROUND

Pulse pressure (PP), a marker of cyclic strain on the arterial wall, is a significant predictor of cardiovascular (CV) risk, particularly regarding the incidence of coronary arterial stenosis. Genes related to haemostatic and/or fibrinolytic factors are consistently influenced in vitro by mechanical strain.

OBJECTIVE

The goal of the present study was to determine, in the three genotypes of the plasminogen activator inhibitor (PAI)-1 gene polymorphism, the gender-adjusted difference in the relationships between age and PP in subjects with never treated essential hypertension.

RESULTS

In the studied population, the genotype deletion (D)/D at position -675 of the PAI-1 insertion (I)/D gene polymorphism was associated with a significant increase in the adjusted slope of the curve relating age to PP by comparison with the two other genotypes. No comparable difference in age-related changes in systolic, diastolic or mean blood pressure was found.

CONCLUSION

In subjects with essential hypertension, the PAI-1 I/D gene polymorphism modulates the age-mediated increase of PP, suggesting new insights on the complex interactions between genes, mechanical factors and CV risk.

Significance of Mean Blood Pressure for Blood Pressure Control

The significance of pulse pressure (PP) and mean blood pressure (MBP) for blood pressure (BP) control is unclear. The aim of this study was to examine the relationship between PP and MBP and BP control. We obtained home BP measurements for 117 patients aged 40-75 years with either office systolic BP (SBP) >or= 140 mmHg or office diastolic BP (DBP) >or= 90 mmHg. Patients were treated with 1 to 2 antihypertensive drugs for 6 months to achieve home SBP < 135 mmHg and home DBP < 85 mmHg. At follow-up, 72 patients were taking a single drug with good BP control, 23 were taking two drugs with good BP control, and 22 were taking two drugs without good BP control. Although office SBP and DBP at baseline were similar in the three groups, home SBP and DBP at baseline in the single drug group were lowest among the three groups (P < 0.01). Home MBP at baseline in the single drug group was lowest among the three groups (P < 0.01). Home PP at baseline was highest in the two-drug without good control group (P < 0.001). In multivariate logistic regression analysis, only home MBP at baseline was significantly correlated with a lack of BP control. Home MBP rather than home PP is associated with achieving adequate BP control.

Hypertension in the Elderly

Elderly individuals with hypertension show specific characteristics as a result of advancing arteriosclerosis, a high frequency of isolated systolic hypertension, increased pulse pressure and orthostatic hypotension. The necessity to treat hypertension in the elderly, including isolated systolic hypertension, has been demonstrated in many large-scale intervention trials. Young-old (65-74 years of age) hypertensive patients should be treated the same as nonelderly hypertensive patients. In old-old (75-84 years of age) patients with mild hypertension (140-159/90-99 mm Hg), the recommended target blood pressure (BP) is <140/90 mm Hg. In old-old (75-84 years of age) and oldest-old (> or =85 years of age) patients with systolic BP > or =160 mm Hg, cautious treatment is required. An intermediate target BP of <150 mm Hg is appropriate, followed by a final target BP of <140 mm Hg, if tolerated. Nonmedical therapy, such as salt restriction, exercise and weight reduction, is useful in the elderly. However, individualised management of nonmedical therapy is necessary to avoid deterioration of quality of life resulting from strict management of the patient's lifestyle. Diuretics, calcium channel antagonists, ACE inhibitors and angiotensin II type 1 receptor antagonists have been established as first-line antihypertensive drugs in the elderly. Use of combination therapy helps to achieve target BPs. The starting dose of each drug should be half the usual dose for nonelderly patients, and may be increased at intervals of >4 weeks, with achievement of the target BP in 3-6 months or longer. In hypertensive patients with co-morbid diseases, the target BP should be determined individually and antihypertensive drugs selected bearing in mind the patient's clinical circumstances. Avoiding hypoperfusion of target organs is very important in elderly hypertensive patients. When treating hypertension in elderly patients, the approach should be to identify individual pathophysiological characteristics and lower the BP cautiously and slowly.

Pulse Pressure and Coronary Atherosclerosis Progression in Postmenopausal Women

Pulse pressure, an index of large artery stiffness, has been associated with coronary events. However, mechanisms for this association remain unclear. In this study, we examined the relationship between pulse pressure and the progression of coronary atherosclerosis and the effects of hormone replacement therapy (HRT) on pulse pressure in postmenopausal women with angiographically confirmed coronary disease followed for 3.2 years in the Estrogen Replacement in Atherosclerosis (ERA) trial. In the ERA trial, 309 postmenopausal women (mean age 66±7 years) with coronary disease were randomized to estrogen, estrogen plus progestin, or placebo, and followed for 3.2 years. Ten standardized epicardial segments were measured for minimal diameter values at baseline and follow-up using quantitative coronary angiography. For this study, mixed-model analysis of covariance was used to: (1) test the association between pulse pressure and change in mean minimum diameter (MMD) adjusted for baseline MMD and (2) the effect of HRT on follow-up pulse pressure. After adjustment for potential confounders, there was a significant graded increase in progression of coronary stenosis with increasing quartiles of baseline pulse pressure ( P test for trend=0.0001). The progression rate in women with the highest quartile of baseline pulse pressure was 5-fold higher than in women in the lowest quartile ( P <0.01). In postmenopausal women with coronary disease, increased levels of baseline pulse pressure are associated with subsequent progression of coronary atherosclerosis in postmenopausal women. HRT had no detectable effect on pulse pressure.

Assessment of arterial ventricular coupling changes in patients under therapy with various antihypertensive agents by a non-invasive echocardiographic method

BACKGROUND

The integration between arterial and ventricular function has been studied by mostly invasive techniques. We considered assessing the influence of various antihypertensive medications on arterial-ventricular coupling (AVC) with the use of a non-invasive echocardiographic method.

METHODS

A total of 9037 patients, who had been under treatment for essential arterial hypertension were studied echocardiographically at baseline prior to therapy and after 6 months of antihypertensive monotherapy (diuretics, beta-blockers without intrinsic sympathomimetic activity (ISA), beta-blockers with ISA, a-blockers, angiotensin converting enzyme inhibitors (ACEI), angiotensin II receptor blockers (AIIRA), non-dihydropyridine calcium antagonists, and dihydropyridine calcium antagonists). The AVC was calculated by echocardiographic measurements based on the equation: AVC=ESV/SV (ESV, end systolic volume; SV, stroke volume).

RESULTS

ACEI, AIIRA, and dihydropyridine calcium antagonists decreased (P<0.0001 for all) while diuretics, alpha-blockers, both beta-blocker groups, and non-dihydropyridines increased significantly the AVC values compared to baseline measurements (P<0.0001 for all, except P=0.02 for alpha-blockers). Changes in AVC were the most highly correlated with changes in EF (r=-0.979, P<0.0001).

CONCLUSION

Various antihypertensive drugs have a differential effect on AVC with ACEI, AIIRA, and dihydropyridine calcium antagonists having the most favorable effect on this index. AVC provides a meaningful index of cardiovascular performance in hypertension and offers the possibility of wide employment and serial follow-up in large numbers of patients because of its completely non-invasive nature.

Effects of telmisartan 80 mg and valsartan 160 mg on ambulatory blood pressure in patients with essential hypertension

OBJECTIVES

This trial investigated and compared the antihypertensive efficacy of telmisartan and valsartan, two angiotensin II receptor blockers, used in monotherapy at their maximum recommended dose in hypertensive patients.

METHODS

We studied 70 subjects (32 men and 38 women) aged 47.6 +/- 12.2 (mean +/- SD) years, with mild to moderate essential hypertension; they were randomly assigned to receive monotherapy with either telmisartan (80 mg) or valsartan (160 mg), in the form of a single daily tablet upon awakening. Blood pressure was measured by ambulatory monitoring every 20 min during the day and every 30 min at night for 48 consecutive hours before and after 3 months of treatment. Physical activity was simultaneously monitored every minute by wrist actigraphy to calculate accurately the diurnal and nocturnal means of blood pressure on a per subject basis.

RESULTS

There was a highly significant blood pressure reduction during the 24 h with both drugs. The blood pressure reduction in the 24-h mean was significantly larger for valsartan 160 mg (18.6 and 12.1 mmHg for systolic and diastolic blood pressure, respectively) than for telmisartan 80 mg (10.8 and 8.4 mmHg; P < 0.001 between treatment-groups). There was also a highly significant reduction (P < 0.001) of 6.5 mmHg in the 24-h mean of pulse pressure after valsartan administration only. The trough : peak ratio and the smoothness index were slightly higher in systolic, but similar in diastolic blood pressure, for telmisartan as compared to valsartan.

CONCLUSIONS

Despite a shorter half-life, 160 mg/day valsartan was more effective in lowering blood pressure over 24 h than 80 mg/day telmisartan. Furthermore, valsartan was also more effective in lowering arterial pulse pressure, an observation that may have important therapeutic implications, given the mounting evidence that pulse pressure may be a risk factor for future cardiovascular events.

Arterial stiffness and wave reflection in hypertension: Pathophysiologic and therapeutic implications

Numerous studies performed in the past decade have shown that increased pulse pressure, an indicator of arterial stiffening, is associated with adverse clinical outcomes. Research is now focused on better defining the anatomic and physiologic determinants of increased pulse pressure. Early work considered aortic stiffening to be a passive, irreversible consequence of aging that was accelerated by hypertension. Recent studies suggest that aortic stiffening is dynamic and reversible and that abnormalities in aortic function may play a primary role in the pathogenesis of hypertension. This review summarizes current work on the genesis of increased pulse pressure and abnormal pulsatile load in hypertension, and underscores areas for future research.

Strategies for prevention and management of hypertension throughout life

Hypertension has been acknowledged as one of the greatest and established risk factors for cardiovascular diseases. In this special article, strategies for the prevention and management of hypertension throughout human’s life were discussed. Studies showing the relationship of birth weight and height increase in childhood to future blood pressure suggest that both environments during pregnancy and during childhood and adolescence are important to prevent hypertension. The promotion of a DASH (Dietary Approach to Stop Hypertension) dietary pattern, rich in fruits and vegetables, is important not only for treatment of high blood pressure but also for long-term prevention of blood pressure rise as well. Blood pressure measured in young adulthood can effectively predict long-term risks of cardiovascular and all-cause mortality, so population-wide primary prevention of high blood pressure for young adults is important. Recent large scale cohort studies confirmed that detection and evaluation of hypertension based mainly on systolic blood pressure remains the most practical and easy approach in the general population for young adult, middle-aged, and older men and women. Researchers in Asia are desired to establish high-quality epidemiologic evidences for Asian for the prevention and management of hypertension.

Comparison of four blood pressure indexes for the prediction of 10-year stroke risk in middle-aged and older Asians

Information has been sparse on the comparison of 4 blood pressure (BP) indexes (systolic BP [SBP], diastolic BP [DBP], pulse pressure [PP], and mean BP [MBP]) in relation to long-term stroke incidence, especially in middle-aged and older Asian people. A prospective cohort study was performed in 4989 Japanese (1523 men and 3466 women) aged 35 to 79 at baseline with 10 years of follow-up. End points included stroke incidence (total, ischemic, and hemorrhagic). Multivariate-adjusted hazard ratios with a 1-SD higher value for each BP index were determined by Cox proportional hazard analyses; Wald chi2 tests were used to compare the strength of relationships. Analyses were also done for each of 4 age-gender groups consisting of men and women aged 35 to 64 and 65 to 79 years. During follow-up, 132 participants developed stroke. Adjusted hazard ratios for all strokes were 1.68 for SBP, 1.72 for DBP, and 1.80 for MBP, which were higher than that for PP (1.34). SBP and DBP were related positively to stroke risk after adjustment of each other. PP was not the strongest predictor in any age-gender groups among 4 BP indexes. In men aged 65 to 79 years, SBP showed the strongest relationship to all stoke risk (hazard ratio 1.62) among 4 BP indexes. In women aged 65 to 79 years, hazard ratios for all strokes were 2.48 for MBP, 2.46 for DBP, 2.25 for SBP, and 1.57 for PP. The long-term incident stroke risk of high BP in Asians should be assessed by SBP and DBP together, or by MBP, not by PP.

Blood Pressure Components and Cardiovascular Events in Older Adults: The Rotterdam Study

OBJECTIVES

To compare the strength of the relative risks of systolic (SBP) diastolic blood pressure (DBP) and pulse pressure (PP) as predictors of myocardial infarction and stroke in older adults.

DESIGN

Prospective cohort study.

SETTING

The Rotterdam Study, a Dutch population-based study.

PARTICIPANTS

A total of 4,234 subjects aged 55 and older with no previous myocardial infarction (MI) or stroke at baseline.

MEASUREMENTS

Blood pressure levels at baseline, first MI and stroke, all-cause mortality during follow-up.

RESULTS

During follow-up, 205 subjects had an MI (average follow-up period 7 years), 137 subjects had a stroke (average follow-up period 6.1 years), and 748 subjects died. A 1-standard deviation difference in SBP, DBP, and PP was associated with relative risks of MI of 1.24 (95% confidence interval (CI)=1.06-1.46), 1.07 (0.92-1.25), and 1.25 (1.07-1.48), respectively. Corresponding relative risks for stroke were 1.59 (1.37-1.86), 1.27 (1.10-1.48), and 1.48 (1.27-1.72). For all-cause mortality the corresponding relative risks and 95% CI were 1.21 (1.11-1.31), 1.06 (0.99-1.14), and 1.20 (1.10-1.31).

CONCLUSION

The results of this study suggest that, in a population of apparently healthy older adults, PP is not a better predictor of cardiovascular events and all-cause mortality than SBP.

Angiotensin receptor blockade in the challenging era of systolic hypertension

Systolic blood pressure is a major cardiovascular risk factor which is often associated with arterial stiffness. Markers of arterial stiffness, such as pulse pressure and carotid-femoral pulse wave velocity, have been proved independent predictors of cardiovascular risk. Recent evidence suggests that the renin-angiotensin system is involved in the pathogenesis of systolic hypertension and arterial stiffness. Outcome trials have shown impressive cardiovascular protection by reducing systolic blood pressure (BP) with drug treatment. However, in clinical practice systolic hypertension remains largely uncontrolled, first, because systolic BP goal is more difficult to be reached than diastolic and, second, because physicians are often reluctant to intensify treatment in patients with systolic BP close to 150 mmHg. Recent trials have focused on the effects of antihypertensive drugs not only on blood pressure, but also on pulse pressure and pulse-wave velocity. Blockade of the renin-angiotensin-aldosterone system, using angiotensin-converting enzyme inhibitors and more recently angiotensin receptor blockers, has been shown to provide beneficial effects on arterial stiffness that appear to be independent of their antihypertensive effects. Recent outcome trials have shown significant cardiovascular protection with angiotensin receptor blockers. These drugs have an excellent placebolike profile of adverse effects which is maintained when these drugs are combined with low-dose diuretics. Therefore, an angiotensin receptor blocker-based treatment strategy appears to be an attractive and evidence-based approach for the management of systolic hypertension, the reduction of arterial stiffness and the prevention of cardiovascular disease.

A likely explanation for the J-curve of blood pressure cardiovascular risk

We prospectively tested in the combined original and offspring Framingham cohorts the hypothesis that the increase in cardiovascular disease (CVD) incidence at low diastolic blood pressure (BP) is largely confined to subjects with increased systolic BP and hence an increased pulse pressure. The 10-year risk of 951 nonfatal CVD events and 204 CVD deaths was estimated at diastolic pressures of <80, 80 to 90, and > or =90 mm Hg, according to concomitant systolic BP. An increasing tendency for a J-curve relation of CVD incidence to diastolic BP was observed with successive increments in accompanying systolic BP. In both genders, a statistically significant excess of CVD events was observed at a diastolic BP of <80 mm Hg only when accompanied by a systolic BP of >140 mm Hg that persisted after adjustment for age and associated CVD risk factors. Patients with this condition of isolated systolic hypertension have been shown to benefit from antihypertensive treatment.

Relationship between arterial stiffness and subclinical aortic atherosclerosis

BACKGROUND

Noninvasive measures of arterial compliance may be useful for the detection of subclinical atherosclerosis.

METHODS AND RESULTS

Measures of calf and thigh arterial compliance (MaxV50) were recorded in 267 subjects who also underwent MRI of the distal aorta to quantify distal aorta atherosclerosis. The average of calf and thigh MaxV50 was strongly predictive of extent of aortic atherosclerosis and risk of being in the top quartile of aortic atherosclerosis after adjustment for the Framingham Coronary Risk Score (FCRS) or the combination of the FCRS and C-reactive protein (P<0.0001). The areas under the receiver operating curves predicting the top quartile of gender-specific aortic atherosclerosis were 0.57, 0.60, and 0.75 for models containing the FCRS, the FCRS and C-reactive protein, and the FCRS, C-reactive protein, and the average of calf and thigh MaxV50.

CONCLUSIONS

Lower-extremity arterial compliance may identify subjects with extensive subclinical atherosclerosis. Further studies examining the potential value of arterial stiffness as a screening tool to guide initiation of more aggressive preventive interventions are warranted.

The effect of hypertension as a predictor of risk for congestive heart failure patients over a 10-year period in a newly developed country

AIMS

Cardiovascular disease is the leading cause of mortality and morbidity in the western world and has reached epidemic proportions. The incidence of congestive heart failure (CHD) and hypertension is also rising rapidly in many of the affluent Arab nations and cardiovascular diseases continue to be a leading cause of morbidity and mortality among adult Qataris and Asians residing in Qatar.

OBJECTIVE

The objective of this study is to assess the effect of hypertension among patients admitted to hospital in Qatar with CHD and to identify risk factors that contribute to the development of CHD in hypertensive subjects.

DESIGN

This is a retrospective cohort study.

SETTING

Hamad General Hospital, Hamad Medical Corporation.

SUBJECTS

All patients who were hospitalized with CHD with or without hypertension in the Hamad General Hospital, State of Qatar, from 1991 to 2001.

METHODS

The diagnostic classification of definite CHD was made in accordance with criteria based on the International Classification of Disease, ninth revision (ICD-9].

RESULT

A total of 20,856 patients were treated during the 10-year period; 8446 were Qataris. Among them, 60% were males and 40% females. Among the total patients (3713) hospitalized with CHD, 1744 (46.9%) had hypertension. Furthermore, the incidence of hypertension was slightly higher in males than in females (56.4 vs 43.6%). A statistically significant difference was found between hypertensive and non-hypertensive cases with diabetes mellitus and angina. Hypertensive subjects were more likely to have diabetes (p < 0.001) and angina (p < 0.030). The mortality rate of CHD patients with hypertension was higher among Qataris than among non-Qataris (p < 0.038).

CONCLUSION

Hypertension was the most common risk factor for CHD; it contributed a large proportion of heart failure cases in this population-based sample. Preventive strategies directed toward earlier detection of elevated blood pressure and its control are likely to offer the greatest promise for reducing the incidence of CHD and its associated mortality.

Metabolic syndrome amplifies the age-associated increases in vascular thickness and stiffness

OBJECTIVES

We sought to evaluate whether the clustering of multiple components of the metabolic syndrome (MS) has a greater impact on these vascular parameters than individual components of MS.

BACKGROUND

Intima-media thickness (IMT) and vascular stiffness have been shown to be independent predictors of adverse cardiovascular events. The MS is defined as the clustering of three or more of the cardiovascular risk factors of dysglycemia, hypertension, dyslipidemia, and obesity.

METHODS

Carotid IMT and stiffness were derived via B-mode ultrasonography in 471 participants from the Baltimore Longitudinal Study on Aging, who were without clinical cardiovascular disease and not receiving antihypertensive therapy.

RESULTS

The MS conferred a disproportionate increase in carotid IMT (+16%, p < 0.0001) and stiffness (+32%, p < 0.0001), compared with control subjects. Multiple regression models, which included age, gender, smoking, low-density lipoprotein, as well as each individual component of MS as continuous variables, showed that MS was an independent determinant of both IMT (p = 0.002) and stiffness (p = 0.012). The MS was associated with a greater prevalence of subjects whose values were in the highest quartiles of IMT, stiffness, or both.

CONCLUSIONS

Even after taking into account each individual component of MS, the clustering of at least three of these components is independently associated with increased IMT and stiffness. This suggests that the components of MS interact to synergistically impact vascular thickness and stiffness. Future studies should examine whether the excess cardiovascular risk associated with MS is partly mediated through the amplified alterations in these vascular properties.

Prevention and treatment of stroke in patients with hypertension

BACKGROUND

Each year, stroke occurs in 30.9 million individuals worldwide and is responsible for approximately 4 million deaths. In the United States, it is the third leading cause of death, occurring with greater frequency than myocardial infarction in patients with hypertension. The greatest burden of stroke, apart from death, is serious long-term physical and mental disability. Stroke survivors often experience physical handicap, depression, and cognitive dysfunction, which together affect their daily functioning, quality of life, and survival. The treatment of stroke is associated with extremely high costs, with stroke-related illnesses responsible for >$49 billion in the United States in 2002. Despite intensive research efforts, few effective treatments are available once stroke has occurred; thus, stroke prevention should be a primary focus for all health care providers.

OBJECTIVE

The purpose of this article was to review the epidemiology and burden of stroke in terms of disability, quality of life, and cost of care, and to summarize the evidence for treatments having therapeutic benefit, with an emphasis on antihypertensive agents.

METHODS

Relevant studies were identified through a MEDLINE search of English-language articles published between 1990 and 2004. The search terms were stroke, epidemiology, economic impact, disability, quality of life, hypertension, drug therapy, and angiotensin II-receptor antagonists. Articles describing major clinical studies, new data, or new mechanisms pertinent to the therapy of stroke were selected for review.

CONCLUSIONS

Identifying and modifying key risk factors is crucial to reducing the morbidity and mortality of stroke. Hypertension is one of the most important risk factors for stroke, and treatment with a variety of antihypertensive agents reduces the risk. Recent evidence suggests that the angiotensin II (ATII)-receptor antagonist losartan may offer advantages beyond blood pressure lowering, including attenuation of the central aortic reflected pressure wave, molecule-specific properties, and neural protective influences on brain ATII type 2 receptors.

Pulse pressure, heart rate, and drug treatment of hypertension

Peak-systolic blood pressure (SBP) and end-diastolic blood pressure (DBP) have been considered the exclusive mechanical factors predicting cardiovascular (CV) risk in populations of normotensive and hypertensive subjects. The purpose of this review is to show that in addition to SBP and DBP, other hemodynamic indices that have particular relevance for coronary complications and originate from pulse pressure (PP) should be taken into account, namely brachial PP and, potentially, heart rate (HR). In normotensive and hypertensive populations, increased PP is an independent predictor for myocardial infarction, more powerful than SBP, even in hypertensive subjects under successful antihypertensive drug therapy. Increased HR is an additional CV risk factor, acting particularly through the presence of an enhanced PP x HR product. Such findings, observed during a period in which standard antihypertensive agents are known to reduce SBP and PP to a much lesser extent than DBP, require the development of intervention trials using drugs acting specifically on SBP, PP, and arterial stiffness.

Cardiac calcification in renal patients: what we do and don't know

Cardiovascular (CV) disease is one of the major causes of mortality in patients with renal diseases, with an increased odds ratio of mortality with risk factors as diverse as blood pressure (high or low), cholesterol level (high or low), left ventricular hypertrophy, vascular stiffness, chronic inflammation, and hyperhomocysteinemia. Mainly cross-sectional studies of renal patients showed excess CV calcification (CVC) compared with the general population, but a clear link between calcification and subsequent mortality is tenuous to date. Several factors have been incriminated to explain the increase in CVC in this particular population. Increased duration of dialysis therapy, dyslipidemia, altered calcium-phosphorus metabolism, and chronic inflammation have all been associated with increased CVC. However, with the shortage of large, observational, population-based, prospective studies tracking these potential risk factors and the pathogenesis of CVC in renal patients not yet sufficiently understood, it is difficult with the present state of knowledge to make robust recommendations about care strategies. The purpose of this review is to examine the 10 available studies of renal patients that have used modern CVC imaging and quantification techniques for clues to likely targets for future interventional studies.

Arterial stiffness and function in end-stage renal disease

Cardiovascular disease is a major cause of mortality in patients with end-stage renal disease, with damage to arteries as a major contributing factor. Arterial stiffness is a factor associated with high systolic and pulse pressure in these patients and is a strong independent factor associated with morbidity and mortality. Arterial stiffness is one of the principal factors opposing left ventricular ejection. The appropriate term to define the arterial factor(s) opposing left ventricular ejection is aortic input impedance. Aortic input impedance depends on TPR, arterial distensibility, and wave reflections. Distensibility defines the capacitive properties of arterial stiffness, whose role it is to dampen pressure and flow oscillations and to transform pulsatile flow and pressure in arteries into a steady flow and pressure in peripheral tissues. Stiffness is the reciprocal value of distensibility. These parameters are blood pressure dependent; arteries become stiffer at high pressure. While distensibility provides information about the elasticity of the artery as a hollow structure, the elastic incremental modulus characterizes the properties of the arterial wall biomaterials independent of vessel geometry. Alternatively, arterial distensibility can be evaluated by measuring pulse wave velocity, which increases with the stiffening of arteries. Arterial stiffening increases left ventricular afterload and alters the coronary perfusion. With increased pulse wave velocity, the wave reflections affects the aorta during systole, which increases systolic pressures and myocardial oxygen consumption and decreases diastolic blood pressure and coronary flow. The arterial stiffness is altered primarily in association with increased collagen content and alterations of extracellular matrix and calcification of the arterial wall. The arterial stiffening estimated by changes in aortic pulse wave velocity and intensity of wave reflections are independent predictors of survival in end-stage renal disease and in the general population. Improvement of arterial stiffening could be obtained by antihypertensive treatments as observed with calcium-channel blockers and angiotensin-converting enzyme inhibitors. Angiotensin-converting enzymes inhibitors increase AC and reduce wave reflections. It has been shown that reversibility of aortic stiffening and use of angiotensin-converting enzyme inhibitors had a favorable independent effect on survival in hypertensive patients with advanced renal disease.

Should pulse pressure become part of the Framingham risk score?

An increased pulse pressure suggests aortic stiffening. New evidence also suggests that pulse pressure is a more sensitive measure of risk than other indexes of blood pressure in middle-aged and older persons. The objective of the study was to relate pulse pressure to the risk of cardiovascular events in the general population, and to assess whether pulse pressure could improve the Framingham risk prediction. A total of 378 men and 391 women over the age of 50 years (mean 62.7 years) were followed. Sex-specific Framingham cardiovascular risk scores were derived from age, systolic pressure, diastolic pressure, total and HDL cholesterol, smoking status and the presence or absence of diabetes mellitus. The cutoff points used to develop a pulse pressure score were calculated by determining the percentile points corresponding to the blood pressure categories in the Framingham risk score. We calculated relative hazard rates by multiple Cox regression. After a median follow-up of 7.2 years (range: 11 months-15 years), a total of 148 cardiovascular events occurred. In Cox regression analysis, a 10 mmHg higher pulse pressure was associated with 31% (P<0.0001) increase in the risk for cardiovascular events (fatal and nonfatal) after adjustment for sex, age, total and HDL cholesterol, smoking and the presence of diabetes mellitus. After adjustment for the aforementioned risk factors, a one-point increment in the blood pressure and pulse pressure scores was associated with a 40 and 48% (both P<0.0001) increase in the risk of fatal and nonfatal cardiovascular events, respectively. When both the blood pressure and pulse pressure scores were forced into a Cox model, only the pulse pressure score remained statistically significant (P<0.0001) with a relative hazard rate of 1.37 (CI: 1.16-1.69). These prospective data suggest that pulse pressure may improve the Framingham risk prediction among middle-aged and older individuals. Further studies, especially in the Framingham cohort, are warranted.

Regulation of cardiovascular calcification

Vascular calcification is highly correlated with cardiovascular disease (CVD) and is a significant predictor of cardiovascular events, especially in high risk patients such as the end stage renal disease (ESRD) population. Vascular calcification can lead to serious problems including valve stenosis, decreased vascular compliance, calciphylaxis, and even sudden death. However, the contribution of vascular calcification to progression of atherosclerosis is unknown and needs more study. Biochemical, histological, and genetic studies indicate that vascular calcification is actively regulated and involves both positive and negative modulators. Several nonmutually exclusive theories to account for vascular calcification based on current studies are discussed.

Association between pulse pressure, carotid intima–media thickness and carotid and/or iliofemoral plaque in hypertensive patients

Increased common carotid artery intima-media thickness (CCA-IMT) and carotid and/or iliofemoral (C/IF) plaque are frequent in subjects treated for hypertension, but their association with pulse pressure (PP) has rarely been studied. Using ultrasound techniques, CCA-IMT and C/IF plaques were studied in 323 hypertensive subjects, who were classified into four groups according to the adequacy of blood pressure (BP) control (systolic BP (SBP) <140 mmHg and diastolic BP (DBP) <90 mmHg) and PP (high or low). After adjustment for confounding variables, an increase in CCA-IMT was the only factor significantly and independently associated with high PP, irrespective of the effectiveness of blood pressure control and of antihypertensive drug treatment. CCA-IMT correlated with age, PP, waist-to-hip ratio, tobacco consumption, and heart rate. C/IF plaques correlated with age, tobacco consumption, diabetes mellitus, and dyslipidaemia. To conclude, even with SBP<140 mmHg and DBP<90 mmHg on treatment, hypertensive subjects may have increased CCA-IMT values and C/IF plaque. Four cardiovascular risk factors seem to be involved in these alterations, namely tobacco consumption, dyslipidaemia, diabetes and increased PP. Only the latter factor does not have a standardized effective treatment.

Angiotensin-converting enzyme D/I gene polymorphism and age-related changes in pulse pressure in subjects with hypertension

Background- Few studies have examined the possible influence of gene polymorphisms on the increase of systolic blood pressure (SBP) and pulse pressure (PP) with age, although in older populations, SBP>160 mm Hg or PP>60 mm Hg are strong mechanical factors predicting cardiovascular mortality.

METHODS AND RESULTS

This cross-sectional study involved 315 men and 154 women with either systolic-diastolic or isolated systolic hypertension. Using polymerase chain reaction, the angiotensin-converting enzyme (ACE) D/I gene polymorphism was investigated separately in men and women, enabling us to determine the relationships between age and PP, SBP, and diastolic blood pressure (DBP) for each genotype in each population. In men, most of which were under 50 years of age, the slope of the age-PP and age-SBP (but not age-DBP) relationships differed significantly between genotypes (P=0.0096 and 0.0175). The interslope difference was unmodified after adjustments involving all of the following factors together: plasma glucose, cholesterol, creatinine, potassium, body weight, tobacco consumption, mean blood pressure, and previous antihypertensive therapy. Adjustment of the two latter parameters alone significantly attenuated the interslope difference. Based on logistic regressions, the DD genotype was shown to independently predict a PP>60 mm Hg but not a SBP>160 mm Hg.

CONCLUSIONS

In men, the ACE D/I gene polymorphism independently modulates age-related increase of PP, and potentially modulates the resulting cardiovascular risk. This finding requires the development of long-term follow-up.

Ambulatory Pulse Pressure, Left Ventricular Hypertrophy and Function in Arterial Hypertension

BACKGROUND

A wide pulse pressure (PP) can provide important risk assessment information about myocardial infarction, carotid artery atherosclerosis, and global cardiovascular risk. Ambulatory pulse pressure (APP) does not have a well-known prognostic value in hypertensive patients.

METHODS

To evaluate the relationship among high APP, atrial volumes, and cardiac function, an observational study was performed on 108 untreated non-elderly hypertensive patients (mean age 54.23 +/- 7.12). Twenty-four-hour ambulatory blood pressure monitoring, Doppler and echocardiographic measurements of systolic, diastolic function, left and right atrial volumes, left ventricular mass index and dimensions, were performed in subjects with both clinic and APP > 60 mmHg (APP1 Group). A control group of hypertensive selected subjects with both clinic and APP < 60 mmHg was chosen (APP 2 Group).

RESULTS

The APP1 group showed left atrial volume enlargement, high left ventricular mass index, and impaired diastolic function. A positive correlation was found in the APP1 group results among left ventricular end diastolic diameter (r = 0.39, P < 0.01), left atrial volume (0.38, P < 0.05), and left ventricular mass index (r = 0.33, P < 0.05); clinic PP showed a statistically significant correlation with left atrial volume, left ventricular end diastolic diameter, and left ventricular mass index only in the APP1 group.

CONCLUSIONS

These results suggest that elevated APP can be considered an effective predictor of cardiovascular risk in hypertensive subjects. In these patients echocardiographic evaluation of left ventricular function and morphology can increase the prognostic value of PP.

Arterial stiffness, wave reflections, and the risk of coronary artery disease

BACKGROUND

Increased arterial stiffness, determined invasively, has been shown to predict a higher risk of coronary atherosclerosis. However, invasive techniques are of limited value for screening and risk stratification in larger patient groups.

METHODS AND RESULTS

We prospectively enrolled 465 consecutive, symptomatic men undergoing coronary angiography for the assessment of suspected coronary artery disease. Arterial stiffness and wave reflections were quantified noninvasively using applanation tonometry of the radial artery with a validated transfer function to generate the corresponding ascending aortic pressure waveform. Augmented pressure (AP) was defined as the difference between the second and the first systolic peak, and augmentation index (AIx) was AP expressed as a percentage of the pulse pressure. In univariate analysis, a higher AIx was associated with an increased risk for coronary artery disease (OR, 4.06 for the difference between the first and the fourth quartile [1.72 to 9.57; P<0.01]). In multivariate analysis, after controlling for age, height, presence of hypertension, HDL cholesterol, and medications, the association with coronary artery disease risk remained significant (OR, 6.91; P<0.05). The results were exclusively driven by an increase in risk with premature vessel stiffening in the younger patient group (up to 60 years of age), with an unadjusted OR between AIx quartiles I and IV of 8.25 (P<0.01) and a multiple-adjusted OR between these quartiles of 16.81 (P<0.05).

CONCLUSIONS

AIx and AP, noninvasively determined manifestations of arterial stiffening and increased wave reflections, are strong, independent risk markers for premature coronary artery disease.

Pulse pressure is associated with age and cardiovascular disease in type 1 diabetes

OBJECTIVE

Type 1 diabetic individuals are thought to have increased arterial stiffness, and are at high risk for cardiovascular disease. However, it is not known whether increased arterial stiffness in type 1 diabetes causes cardiovascular disease. To explore this issue, the present study investigated the association, in type 1 diabetes, of age and pulse pressure, an estimate of arterial stiffness, and the influence of the presence of microvascular complications on this association. In addition, we determined the association of mean arterial pressure and pulse pressure with incident cardiovascular disease.

METHODS

We studied a cohort of 3250 type 1 diabetic individuals of the EURODIAB Prospective Complications Study. Mean age and median follow-up were 33 and 7.4 years. One hundred and sixty-three individuals developed a first manifestation of cardiovascular disease during follow-up. Linear regression analysis was used to determine the association of age with pulse pressure. Relative risks of cardiovascular disease were estimated by Cox regression analyses adjusted for age, sex and mean arterial pressure or pulse pressure.RESULTS In cross-sectional analyses, age was associated with pulse pressure (P < 0.001) and this association was stronger in the presence of micro- or macroalbuminuria or retinopathy than in their absence (interaction for albuminuria, P < 0.001; interaction for retinopathy, P < 0.001). In prospective analyses, both mean arterial pressure and pulse pressure were associated with cardiovascular disease [adjusted relative risks and (95% confidence interval) per 10 mmHg increase were 1.08 (0.94-1.24) and 1.09 (0.98-1.21)].

CONCLUSIONS

This study shows an association of age with pulse pressure in young type 1 diabetic individuals, which is stronger in the presence of microvascular complications. In addition, both mean arterial pressure and pulse pressure are associated with incident cardiovascular disease. These findings support the concept of early vascular ageing in type 1 diabetes, especially in the presence of microvascular complications.

Arterial compliance adds to conventional risk factors for prediction of angiographic coronary artery disease

BACKGROUND

Arterial compliance is related to left ventricular hypertrophy and risk for cardiovascular disease events; however, its association with coronary artery stenosis remains uncertain. We sought to assess the relation between lower extremity arterial compliance and presence of angiographically defined coronary artery disease.

METHODS

Lower extremity arterial compliance was measured with the use of a noninvasive air plethysmography technique in 376 subjects undergoing routine diagnostic coronary angiography.

RESULTS

Measures of calf arterial compliance were significantly associated with the presence of one or more stenoses > or =50% compared with no stenoses, even after adjustment for age, sex, smoking, diabetes, hypertension, hypercholesterolemia, and obesity (P =.03). Measures of thigh arterial compliance were also lower in subjects with disease, although this association did not reach statistical significance (P =.07). Receiver operator curves illustrate the incremental predictive ability of calf arterial compliance over and above age, sex, and conventional risk factors.

CONCLUSIONS

Lower extremity arterial compliance is associated with presence of significant coronary stenoses in a cardiac catheterization laboratory referral population. This observation lends support for additional efforts to determine the utility of vascular stiffness measures in both clinical and pre-clinical populations to guide treatment and prevention efforts.

Determinants of elevated pulse pressure in middle-aged and older subjects with uncomplicated systolic hypertension: the role of proximal aortic diameter and the aortic pressure-flow relationship

BACKGROUND

Elevated pulse pressure (PP) is associated with increased cardiovascular risk and is thought to be secondary to elastin fragmentation with secondary collagen deposition and stiffening of the aortic wall, leading to a dilated, noncompliant vasculature.

METHODS AND RESULTS

By use of calibrated tonometry and pulsed Doppler, arterial stiffness and pulsatile hemodynamics were assessed in 128 subjects with uncomplicated systolic hypertension (supine systolic pressure > or =140 mm Hg off medication) and 30 normotensive control subjects of comparable age and gender. Pulse-wave velocity was assessed from tonometry and body surface measurements. Characteristic impedance (Zc) was calculated from the ratio of change in carotid pressure and aortic flow in early systole. Effective aortic diameter was assessed by use of the water hammer equation. Hypertensives were heavier (P<0.001) and had higher PP (P<0.001), which was attributable primarily to higher Zc (P<0.001), especially in women. Pulse-wave velocity was higher in hypertensives (P=0.001); however, this difference was not significant after adjustment for differences in mean arterial pressure (MAP) (P>0.153), whereas increased Zc remained highly significant (P<0.001). Increased Zc in women and in hypertensive men was attributable to decreased effective aortic diameter, with no difference in wall stiffness at comparable MAP and body weight.

CONCLUSIONS

Elevated PP in systolic hypertension was independent of MAP and was attributable primarily to elevated Zc and reduced effective diameter of the proximal aorta. These findings are not consistent with the hypothesis of secondary aortic degeneration, dilation, and wall stiffening but rather suggest that aortic function may play an active role in the pathophysiology of systolic hypertension.

Pulse pressure: an important tool in cardiovascular pharmacology and therapeutics

Epidemiological studies in the past decade have stressed the importance of pulse pressure (PP) as an independent risk factor for cardiovascular morbidity and mortality. We briefly review the epidemiological evidence and discuss the pathophysiological mechanisms which involve arterial stiffness and wave reflections in older patients. We discuss the therapeutic consequences of targeting PP rather than systolic (S) or diastolic (D) blood pressure (BP) when using antihypertensive agents. With this line of evidence it is important, first, to determine what minimal PP level indicates cardiovascular risk and, second, to note that an increasing number of clinical studies indicate that PP is poorly sensitive to placebo, while SBP and DBP are conversely highly sensitive. Finally, on the basis of large-scale intervention trials, PP seems to be an appropriate tool for studies of clinical pharmacology and therapeutics in the fields of hypertension, congestive heart failure and other cardiovascular diseases.

Genome-wide multipoint parametric linkage analysis of pulse pressure in large, extended utah pedigrees

High pulse pressure, a measure of arterial aging, is an important predictor of cardiovascular and general mortality. It has been suggested that the genetic etiology of pulse pressure is the same as systolic blood pressure. We performed a genome-wide, multipoint, parametric linkage analysis in 26 large, extended Utah pedigrees to locate genes affecting pulse pressure. Four parametric models were considered, including dominant and recessive modes of inheritance involving genes for high and low pulse pressure. Linkage analysis revealed 11 regions with a logarithm of the odds (LOD) >1.5, including 2 regions attaining genome-wide suggestive evidence for linkage after accounting for multiple tests. Inspecting pedigree-specific multipoint linkage evidence suggested that these 2 regions localized to 15.7 cM on chromosome 8p (LOD=2.89), between markers D8S136 and D8S1477, and 20.0 cM on chromosome 12q (LOD=2.59), between D12S1300 and D12S2070. Both regions were identified better by pulse pressure compared with equivalent analyses with systolic or diastolic blood pressure. Results for pulse pressure overlapped favorably with those of others for related blood pressure phenotypes and support the hypothesis that genes with pleiotropic effects on blood pressure phenotypes do exist, but that the genetic etiologies are not identical. In conclusion, our results suggest that pulse pressure might be of use for identifying genes involved in blood pressure phenotypes and arterial aging.

Cardiovascular calcifications in uremic patients: clinical impact on cardiovascular function

Cardiovascular disease is the leading cause of mortality among patients with ESRD (chronic kidney disease stage 5). Left ventricular hypertrophy and arterial diseases are the two principal risk factors for cardiovascular mortality in hemodialysis patients. Epidemiologic studies show that damage to large conduit arteries contributes to morbidity and mortality in patients with chronic kidney disease. Atherosclerosis is primarily an intimal disease characterized by the presence of plaques and occlusive lesions. Although atherosclerosis is the most frequent underlying cause of cardiovascular disease in patients with ESRD, it represents only one form of structural response to metabolic and hemodynamic alterations that interfere with the process of aging. Arterial alterations in ESRD include nonocclusive arterial remodeling accompanying the growing hemodynamic burden and humoral abnormalities that are associated with chronic uremia. The consequences of these alterations are different from those attributed to atherosclerotic plaques and are characterized principally by hardening (stiffening) of arteries. Arteriosclerosis, characterized by stiffening of the aorta and large capacitative arteries, is a major determinant of left ventricular pressure overload and of abnormal coronary perfusion. Atherosclerosis and arteriosclerosis are frequently comorbid and characterized by a high degree of both intimal and medial calcifications in patients with ESRD. The extent of calcifications and the degree of arterial stiffening are independent predictors of mortality. Studies in patients with ESRD have shown that attenuation of arterial stiffness can have a favorable effect, associated with regression of left ventricular hypertrophy, on survival. Calcium-free, metal-free phosphate binders such as sevelamer can reduce calcification scores.

The Importance of Systolic Blood Pressure Control and Cardiovascular Disease Prevention

Hypertension affects up to 75% of individuals 60 years of age and older. Cardiovascular risk is related to increases in systolic blood pressure and pulse pressure and to decreases in diastolic blood pressure, but systolic blood pressure reduction is the major target for improving outcomes in the elderly patient. Hypertension therapy in older individuals should include lifestyle modification, especially weight loss and sodium restriction, which may decrease the need for antihypertensive medication. The starting dose of medication should be one half that used in younger patients. If low initial doses are used, significant attention must be paid to adequate titration; combination therapy is usually required for optimal blood pressure control. The initial agent chosen is rarely the final agent used to achieve the recommended minimal systolic blood pressure goal of less than 140 mm Hg. If more than one agent is required, a diuretic should be included as one of the agents chosen. Although the reduction of blood pressure should occur more gradually in the older patient, the treatment goals should be similar and determined by the underlying concomitant disorder. The minimum goal should remain less than 140/90 mm Hg, with lower goals in diabetic patients and those with renal disease. Patients with isolated systolic hypertension should have a minimum systolic blood pressure goal of less than 140 mm Hg.