Relationships between cardiovascular remodelling and the pulse pressure in never treated hypertension

Maternal exposure to perfluorobutane sulfonate (PFBS) during pregnancy: evidence of adverse maternal and fetoplacental effects in New Zealand White (NZW) rabbits

Perfluorobutanesulfonic acid (PFBS) is a replacement for perfluorooctanesulfonic acid (PFOS) that is increasingly detected in drinking water and human serum. Higher PFBS exposure is associated with risk for preeclampsia, the leading cause of maternal and infant morbidity and mortality in the United States. This study investigated relevant maternal and fetal health outcomes after gestational exposure to PFBS in a New Zealand White rabbit model. Nulliparous female rabbits were supplied drinking water containing 0 mg/l (control), 10 mg/l (low), or 100 mg/l (high) PFBS. Maternal blood pressure, body weights, liver and kidney weights histopathology, clinical chemistry panels, and thyroid hormone levels were evaluated. Fetal endpoints evaluated at necropsy included viability, body weights, crown-rump length, and liver and kidney histopathology, whereas placenta endpoints included weight, morphology, histopathology, and full transcriptome RNA sequencing. PFBS-high dose dams exhibited significant changes in blood pressure markers, seen through increased pulse pressure and renal resistive index measures, as well as kidney histopathological changes. Fetuses from these dams showed decreased crown-rump length. Statistical analysis of placental weight via a mixed model statistical approach identified a significant interaction term between PFBS high dose and fetal sex, suggesting a sex-specific effect on placental weight. RNA sequencing identified the dysregulation of angiotensin (AGT) in PFBS high-dose placentas. These results suggest that PFBS exposure during gestation leads to adverse maternal outcomes, such as renal injury and hypertension, and fetal outcomes, including decreased growth parameters and adverse placenta function. These outcomes raise concerns about pregnant women's exposure to PFBS and pregnancy outcomes.

Imaging of functional and structural alterations of large arteries after acute ischaemic atherothrombotic stroke or acute coronary syndromes

BACKGROUND

Non-invasive methods allow the evaluation of structural and functional arterial abnormalities. So far, no study has focused on the comparison of vascular parameters by type of cardiovascular event.

METHODS

In this pilot study, cardiovascular risk factors, carotid parameters, carotid-to-femoral pulse wave velocity (PWV), brachial flow-mediated dilation and ambulatory blood pressure were assessed in patients who presented with acute coronary syndromes (ACS) or ischaemic atherothrombotic stroke (IAS). Groups were matched for age and gender.

RESULTS

Prevalences of hypertension, diabetes and dyslipidaemia and heredity, smoking and body mass index were similar in the ACS (n=50) and IAS (n=50) groups. Carotid intima-media thickness (IMT) and PWV were significantly higher in the IAS vs. ACS group (769±180 vs. 701±136 μm; P=0.039 and 12.5±3.5 vs. 10.7±2.4 m/s; P=0.006). Carotid distensibility was significantly lower in the IAS vs. ACS group (16.2±3.2 vs. 18.9±7.6 10(-3)/kPa; P=0.02). These differences persisted after adjustment for blood pressure for carotid distensibility but not for PWV. The prevalences of endothelial dysfunction and carotid plaques were not significantly different in the ACS and IAS groups (86% and 74%; 80% and 78%). In a multivariable model, carotid distensibility remained associated with ACS (odds ratio 1.19; 95% confidence interval 1.03-1.38; P=0.016).

CONCLUSIONS

Stiffness and carotid wall thickness were higher in IAS than in ACS patients. These differences may support the interest in new therapeutic targets for cardiovascular secondary prevention.

NCT NO

NCT00926874.

Relationship between long-term exposure to low-level arsenic in drinking water and the prevalence of abnormal blood pressure

Arsenic increases the risk and incidence of cardiovascular disease. To explore the impact of long-term exposure to low-level arsenic in drinking water on blood pressure including pulse pressure (PP) and mean arterial blood pressure (MAP), a cross-sectional study was conducted in 2010 in which the blood pressure of 405 villagers was measured, who had been drinking water with an inorganic arsenic content <50 μg/L. A multivariate logistic regression model was used to estimate odds ratios and 95% confidence intervals. After adjusting for age, gender, Body Mass Index (BMI), alcohol consumption and smoking, the odds ratios showed a 1.45-fold (95%CI: 0.63-3.35) increase in the group with >30-50 years of arsenic exposure and a 2.95-fold (95%CI: 1.31-6.67) increase in the group with >50 years exposure. Furthermore, the odds ratio for prevalence of abnormal PP and MAP were 1.06 (95%CI: 0.24-4.66) and 0.87 (95%CI: 0.36-2.14) in the group with >30-50 years of exposure, and were 2.46 (95%CI: 0.87-6.97) and 3.75 (95%CI: 1.61-8.71) for the group with >50 years exposure, compared to the group with arsenic exposure ≤ 30 years respectively. Significant trends for Hypertension (p<0.0001), PP (p<0.0001) and MAP (p=0.0016) were found. The prevalence of hypertension and abnormal PP as well as MAP is marked among a low-level arsenic exposure population, and significantly increases with the duration of arsenic exposure.

Hypervolemia rather than arterial calcification and extracoronary atherosclerosis is the main determinant of pulse pressure in hemodialysis patients

INTRODUCTION

Pulse pressure (PP) has been reported as an independent predictor of cardiovascular mortality in hemodialysis patients. In this study, we aimed to investigate association of PP with echocardiographic and vascular structural changes such as atherosclerosis and arterial calcifications in HD patients.

PATIENTS AND METHODS

In this cross-sectional study, 108 chronic hemodialysis patients (49 male, 59 female, mean age: 46 ± 13 years) were included. Biochemical analyses, echocardiographic and high-resolution carotid Doppler examinations were done. Aortic wall and coronary artery calcifications were measured with electron beam computed tomography. The degree of carotid artery stenosis was measured at four different sites (communis, bulbus, interna and externa) in both carotid arteries.

RESULTS

PP was strongly correlated with systolic (r: 0.82) and diastolic (r: 0.33) blood pressure, left ventricular mass index (r: 0.58), left ventricle end diastolic diameter (r: 0.38) and weakly correlated with aortic wall calcification score (r: 0.26) and carotid plaque score (r: 0.27), but not with coronary artery calcification score. Patients with carotid plaque had higher PP than patients without plaque (50 ± 16 mmHg versus 44 ± 14 mmHg, P = 0.05). Patients were divided into three groups according to aortic wall calcification score. PP was significantly higher in patients with higher aortic wall calcification (54 ± 16 mmHg) than patients with lower aortic wall calcification (44 ± 15 mmHg, P = 0.04). However, on multivariate linear regression analysis for predicting PP, the only significant factor retained was left ventricle end diastolic diameter.

CONCLUSION

PP was weakly associated with large vessel calcification and atherosclerosis in hemodialysis patients. The bulk of the effect on PP seems to be due to hypervolemia.

Choroidal blood-flow responses to hyperoxia and hypercapnia in men with obstructive sleep apnea

STUDY OBJECTIVES

Obstructive sleep apnea (OSA) impacts on macrovasculature and autonomic function and may therefore interfere with ocular microvascular regulation. We hypothesized that choroidal vascular reactivity to hyperoxia and hypercapnia was altered in patients with OSA compared with matched control subjects and would improve after treatment with continuous positive airway pressure (CPAP).

METHODS

Sixteen healthy men were matched 1:1 for body mass index, sex, and age with 16 men with newly diagnosed OSA without comorbidities. Subjects underwent sleep studies, 24-hour blood pressure monitoring, arterial stiffness measurements, and cardiac and carotid echography. Overall, patients were middle-aged, lean, and otherwise healthy except for having OSA with a limited amount of desaturation, with, at most, subclinical lesions of the cardiovascular system, stage 1 hypertension, or both. Choroidal laser Doppler flowmetry provides a unique opportunity to assess microvascular function by measuring velocity, (ChBVel), volume (ChBVol), and relative subfoveal choroidal blood flow (ChBF). Vascular choroidal reactivity was studied during hyperoxia and hypercapnia (8% CO2) challenges before and after treatment with nasal CPAP.

RESULTS

Patients with OSA and control subjects exhibited similar choroidal reactivity during hyperoxia (stability of choroidal blood flow) and hypercapnia (significant increases in ChBVel of 13.5% and in ChBF of 16%). Choroidal vasoreactivity to CO2 was positively associated with arterial stiffness in patients with OSA. Gas choroidal vasoreactivity was unchanged after 6 to 9 months of CPAP treatment.

CONCLUSION

This study showed unimpaired choroidal vascular reactivity in otherwise healthy men with OSA. This suggests that patients with OSA, without comorbidities, have long-term adaptive mechanisms active in ocular microcirculation.

Alterations of pulse pressure stimulate arterial wall matrix remodeling

The effect of pulse pressure on arterial wall remodeling has not been clearly defined. The objective of this study was to evaluate matrix remodeling in arteries under nonpulsatile and hyperpulsatile pressure as compared with arteries under normal pulsatile pressure. Porcine carotid arteries were cultured for 3 and 7 days under normal, nonpulsatile, and hyperpulsatile pressures with the same mean pressure and flow rate using an ex vivo organ culture model. Fenestrae in the internal elastic lamina, collagen, fibronectin, and gap junction protein connexin 43 were examined in these arteries using confocal microscopy, immunoblotting, and immunohistochemistry. Our results showed that after 7 days, the mean fenestrae size and the area fraction of fenestrae decreased significantly in nonpulsatile arteries (51% and 45%, respectively) and hyperpulsatile arteries (45% and 54%, respectively) when compared with normal pulsatile arteries. Fibronectin decreased (29.9%) in nonpulsatile arteries after 3 days but showed no change after 7 days, while collagen I levels increased significantly (106%) in hyperpulsatile arteries after 7 days. The expression of connexin 43 increased by 35.3% in hyperpulsatile arteries after 7 days but showed no difference in nonpulsatile arteries. In conclusion, our results demonstrated, for the first time, that an increase or a decrease in pulse pressure from its normal physiologic level stimulates structural changes in the arterial wall matrix. However, hyperpulsatile pressure has a more pronounced effect than the diminished pulse pressure. This effect helps to explain the correlation between increasing wall stiffness and increasing pulse pressure in vivo.

Early cardiovascular abnormalities in newly diagnosed obstructive sleep apnea

Obstructive sleep apnea (OSA) is associated with high cardiovascular morbidity and mortality. Recent studies have shown that it is associated with atherosclerosis and left ventricular dysfunction markers. The aim of this study was to assess the cardiovascular effects of OSA depending on its severity, in patients without clinically diagnosed cardiovascular disease. One hundred thirty newly diagnosed, nondiabetic OSA patients (mean age 49 +/- 10 years), without vasoactive treatment were included. They underwent clinical and ambulatory blood pressure measurements, echocardiography, carotid ultrasound examination, and a carotid-femoral pulse wave velocity (PWV) measurement. Seventy-five percent of the subjects were hypertensive according to the clinical or ambulatory measurement. More patients with the most severe forms (respiratory disturbance index >37/hour) had a nondipper profile (52% vs 34%; P = 0.025) and their left ventricular mass was higher (40 +/- 7 vs 36 +/- 8 g/m, p = 0.014). This last parameter was independently and inversely associated with mean nocturnal oxygen saturation (P = 0.004). PWV and carotid intima-media thickness did not differ between one OSA severity group to another, but the prevalence of carotid hypertrophy was higher when mean SaO(2) was below 93.5% (29.5 vs 16%; P = 0.05). Our study shows that in OSA patients without clinically diagnosed cardiovascular disease, there is a significant left ventricular and arterial effect, which is even more marked when OSA is severe.

Effects of candesartan cilexetil on carotid remodeling in hypertensive diabetic patients: the MITEC study

In hypertension and diabetes, early structural changes of the arterial wall precede or support atherosclerosis. There is evidence that some antihypertensive drugs exert an antiathero-sclerotic effect. Over 36 months, we investigated the effect of candesartan cilexetil (CC) on the common carotid intima-media thickness (IMT) vs amlodipine besylate (AML) in patients with type 2 diabetes and mild to moderate essential hypertension. After a 4-week wash-out period, 209 patients were randomized to either CC 8 mg or AML 5 mg once daily for a minimum of 1 month, after which, if BP was not normalized, the dosage was doubled, followed by the addition of hydrochlorothiazide 12.5 mg if necessary. No significant differences were observed between the two groups for change in IMT at M12 (−0.001 vs −0.027 mm/year for CC and AML respectively, p = 0.425), at M24 (−0.033 vs −0.019 mm per year respectively, p = 0.442), and at the last visit (−0.016 vs −0.039 mm per year respectively, p = 0.549). Within the group, comparisons did not show a significant difference in changes in IMT from baseline to the three visits. At the last visit, IMT regression was observed in 52.2% of patients receiving CC and in 51.3% of those receiving AML (p = 0.908). The augmentation in carotid lumen diameter from baseline was statistically greater in the AML group at the last visit (p = 0.034). BP variations during the study were similar in the two groups. The results of this study show that CC and AML treatments may alter identically the natural progression of carotid IMT in hypertensive type 2 diabetic patients.

Masked hypertension in obstructive sleep apnea syndrome

BACKGROUND

Ambulatory blood pressure (BP) monitoring (ABPM) detects subjects with normal clinic but high ambulatory 24-h BP, that is, masked hypertension.

METHODS

One hundred and thirty newly diagnosed obstructive sleep apnea syndrome (OSAS) patients, free of recognized cardiovascular disease were included (111 men, age = 48 +/- 1 years, BMI = 27.6 +/- 0.4 kg/m, respiratory disturbance index (RDI = 42 +/- 2/h). Clinic BP, 24-h ABPM, baroreflex sensitivity (BRS), echocardiography and carotid intima-media thickness (IMT) were assessed.

RESULTS

Forty-one patients (31.5%) were normotensive, 39 (30.0%) exhibited masked hypertension, four (3.1%) white-coat hypertension and 46 (35.4%) hypertension. Significant differences were found between normotensive, masked hypertensive and hypertensive patients in terms of BRS (10.5 +/- 0.8, 8.0 +/- 0.6 and 7.4 +/- 0.4 ms/mmHg, respectively, P < 0.001), carotid IMT (624 +/- 17, 650 +/- 20 and 705 +/- 23 microm, respectively, P = 0.04) and left ventricular mass index (37 +/- 1, 40 +/- 2 and 43 +/- 1 g/height2.7, respectively, P = 0.003). A clinic systolic BP more than 125 and a diastolic BP more than 83 mmHg led to a relative risk (RR) of 2.7 and a 90% positive predictive value for having masked hypertension.

CONCLUSION

Masked hypertension is frequently underestimated in OSAS and is nearly always present when clinic BP is above 125/83 mmHg.

High pulse pressure as a marker of preclinical cardiovascular disease

Increasing attention has been focused on the pathophysiology and prognostic relevance of increased pulse pressure. High systolic pressure increases vascular load whereas low diastolic pressure reduces coronary perfusion pressure, both of which provide pathophysiological explanations for the prognostic value of pulse pressure. In a recent study we have demonstrated that in the presence of either normal or high peripheral resistance, brachial pulse pressure is associated with an increase in left ventricular mass and in arterial stiffness. As indicated in our study, a brachial pulse pressure over 63 mmHg represents a sign of established cardiovascular damage in the setting of arterial hypertension. Accordingly, we suggest elevated brachial pulse pressure should be considered a marker of established preclinical cardiovascular disease rather than a risk factor for the development of arterial disease.

The severity of oxygen desaturation is predictive of carotid wall thickening and plaque occurrence

STUDY OBJECTIVES

To characterize carotid intima-media thickness (IMT) and plaque occurrence in patients with newly diagnosed obstructive sleep apnea (OSA) without known cardiovascular disease.

DESIGN

Prospective study.

SETTING

Sleep Laboratory and Department of Cardiology of Grenoble University Hospital.

PATIENTS AND INTERVENTION

OSA syndrome is associated with an increased cardiovascular risk. Carotid IMT is recognized as a marker of preclinic atheroma. A small number of studies have analyzed large-artery wall modifications in OSA syndrome. Eighty-three patients (74 men; mean age +/- SD, 48 +/- 11 years; mean body mass index, 27.4 +/- 4.2 kg/m(2)) were included. Mean respiratory disturbance index was 40.7 +/- 19.2/h, mean nocturnal arterial oxygen saturation (Sao(2)) was 93.1 +/- 2.0%, and mean percentage of recording time spent at Sao(2) < 90% was 8.6 +/- 16.8%. Clinical BP was measured following European Society of Hypertension/European Society of Cardiology recommendations, and 24-h ambulatory BP monitoring was assessed. Ultrasonography was used to determine the carotid IMT and atheromatous plaque occurrence.

MEASUREMENTS AND RESULTS

Twenty-five of 83 patients (30%) had carotid wall hypertrophy (IMT > 0.8 mm). In a logistic regression model, mean nocturnal Sao(2) < 92% (odds ratio [OR], 3.9; 95% confidence interval [CI], 1.1 to 12.7) was associated with carotid wall hypertrophy. ORs were even higher after adjustment for BP status (OR, 10.6; 95% CI, 1.6 to 50.9 in normotensive patients) and glucose levels (OR, 4.5; 95% CI, 1.0 to 20.9). Mean nocturnal Sao(2) < 92% and minimal nocturnal Sao(2) < 80% (ORs, 3.1 and 3.1; 95% CIs, 1.0 to 9.4 and 1.0 to 8.5, respectively) were associated with the presence of carotid plaque formation independently of the BP status (hypertensive or normotensive).

CONCLUSIONS

The severity of oxygen desaturation appears to be one of the best predictors for carotid IMT and plaque occurrence in OSA patients without known cardiovascular disease. Thus, carotid IMT and plaque formation appeared as early cardiovascular consequences in OSA patients.

Association Between Hemodynamic Profile During Laboratory Stress and Ambulatory Pulse Pressure

Hemodynamic responses underlying blood pressure reactivity to laboratory stress are theoretically linked to cardiovascular pathophysiology. The present study investigated whether a vascular response predicted ambulatory pulse pressure, a known risk factor for cardiovascular disease. A new model of hemodynamic profile, previously developed by the authors, was applied to 24-h ambulatory data from 30 female and 34 male healthy young adults. Of these, 40 were monitored during a naturalistic stressor (university examination). For females, hemodynamic profile significantly predicted nighttime systolic blood pressure, and 24-h, day-, and nighttime diastolic blood pressure, but not ambulatory pulse pressure. A vascular or mixed hemodynamic profile significantly predicted 24-h and daytime ambulatory pulse pressure in males. The findings are consistent with theories of pathogenic mechanisms involving vascular changes and suggest that, for males, a vascular or mixed hemodynamic profile measured during laboratory stress may be a risk marker for cardiovascular disease, by its association with ambulatory pulse pressure.

Does the reduction in systolic blood pressure alone explain the regression of left ventricular hypertrophy?

Systolic blood pressure (SBP) is an important determinant of the development and regression of left ventricular hypertrophy (LVH) in hypertensive humans. However, comparative assessments with other BP components are scarce and generally limited in size. As part of the Progetto Ipertensione Umbria Monitoraggio Ambulatoriale (PIUMA), 743 hypertensive subjects underwent echocardiography and 24-h ambulatory BP monitoring before and after an average of 3.9 years of treatment. The changes in left ventricular mass showed a significant direct association with the changes in 24-h SBP (r=0.40), diastolic blood pressure (DBP) (r=0.33) and pulse pressure (PP) (r=0.35). Weaker associations were found with the changes in clinic BP (r=0.32, 0.31 and 0.16, respectively). In a multivariate linear regression analysis, the changes in 24-h SBP were the sole independent determinants of the changes in left ventricular mass (LVM) according to the following equation: percentage changes in LVM=0.73 x (percentage changes in 24-h SBP) -0.48 (P<0.0001). For any given reduction in 24-h SBP, the reduction in LVM did not show any association with the changes in DBP and PP, either clinic or ambulatory. These data indicate that SBP is the principal determinant of LVH regression in hypertensive humans.

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.

Structural and functional abnormalities of large arteries in the Turner syndrome

OBJECTIVE

To analyse the structural and functional abnormalities in the large arteries in women with the Turner syndrome.

METHODS

Aortic stiffness (assessed by means of the carotid femoral pulse wave velocity), level of amplification of the carotid pressure wave (by applanation tonometry), and carotid remodelling (by high resolution ultrasound) were studied in women with the Turner syndrome. Clinical and ambulatory blood pressures were taken into account in the analysis. Thus, 24 patients with the Turner syndrome and 25 healthy female subjects matched for age were studied.

RESULTS

Women with the Turner syndrome had a higher augmentation index than the controls (Turner, mean (SD) 0.04 (0.14) v controls, -0.14 (0.13), p < 0.001) but a lower peripheral pulse pressure (39 (8) mm Hg v 47 (11) mm Hg, p = 0.010 in the clinic; 44 (5) mm Hg v 47 (6) mm Hg, p = 0.036 during the 24 hour ambulatory recording). The luminal diameter of the common carotid artery and the carotid-femoral pulse wave velocity were similar in the two groups, whereas carotid intima-media thickness tended to be higher in women with the Turner syndrome (0.53 (0.06) mm v 0.50 (0.05) mm, p = 0.06). After correction for body surface area, carotid intima-media thickness and pulse wave velocity were higher in women with the Turner syndrome.

CONCLUSIONS

Vascular abnormalities observed in the Turner syndrome are implicated in the origin of the cardiovascular complications that occur in this syndrome. These abnormalities are morphological but also functional. An increase in the augmentation index can be explained in part by the short height of these patients.

F2-Isoprostane level is associated with the angiotensin II type 1 receptor -153A/G gene polymorphism

Recent studies have shown that F2-isoprostane levels-a marker for lipid peroxidation-are increased in human renovascular hypertension but not in essential hypertension. Angiotensin II specifically stimulates F2-isoprostane production through activation of the AT1 receptor. The objective was to determine whether there is a relationship between the level of oxidative stress evaluated by measuring urinary F2-isoprostanes levels and polymorphisms of genes involved in the renine angiotensin aldosterone system (RAAS) regulation. The population studied included 100 subjects, 65 of whom were healthy normotensives; the other 35 were suffering from untreated, essential hypertension. The polymorphisms studied concern the genes encoding angiotensin I-converting enzyme (ACE/in16del/ins), angiotensin II receptor type I (AGTR1/A+39C[A+1166C] and AGTR1/A-153G), angiotensinogen (AGT/M235T), and aldosterone synthase (CYP11B2/T344C). Oxidative stress was evaluated by measuring urinary F2-isoprostanes levels. The characteristics of the population were as follows: men/women = 46/56; age = 50 +/- 10 years; BMI = 24 +/- 3 kg/m2; SBP = 131.7 +/- 17.2 mm Hg; DBP = 84.6 +/- 10.4 mm Hg. In univariate analysis, urinary F2-isoprostane levels were significantly lower in the presence of the G allele of AGTR1/A-153G (56 +/- 17 vs 76 +/- 39 pmol/mmol creatinine; P < 0.001, and P < 0.01 after Bonferroni correction for 10 tests). In multivariate analysis, taking into account BP, age, gender, BMI, plasma glucose, and total cholesterol, the G allele of AGTR1/A-153G is linked independently to urinary F2-isoprostanes level (P < 0.01). Our data suggest that F2-isoprostane level depends at least in part on the A-153G polymorphism of the angiotensin II AT1 receptor gene. The clinical and prognostic relevance of this polymorphism requires further investigation.

Predictors of Congestive Heart Failure Mortality in Elderly People From the General Population The CArdiovascular STudy in the ELderly (CASTEL)

Congestive heart failure (CHF) is highly prevalent in the elderly. The aim of this study was to identify the predictors of CHF mortality in patients over 65 years of age who were free of CHF at initial screening. A total of 3,282 elderly subjects were recruited in a population-based frame and 12-year events were recorded. Continuous items were divided into tertiles and for each tertile adjusted the relative risk (RR) with 95% confidence intervals (CI) was derived in both genders from multivariate Cox analysis of CHF mortality. Age > or = 72 years ([RR]: 2.24; 95% CI 1.56 - 3.24), male gender ([RR]: 1.4; 95%CI 1.02 - 1.76), clinical history of coronary artery disease ([RR]: 1.25; 95% CI 1.02 - 1.76), pulse pressure > or = 79 mmHg ([RR]: 1.33; 95% CI 1.03 - 1.87), heart rate > or = 81 bpm ([RR]: 1.32; 95% CI 1.10 - 1.96), atrial fibrillation ([RR]: 1.82; 95% CI 1.18 - 2.81), left ventricular hypertrophy ([RR]: 1.42; 95% CI 1.01 - 2.02), diabetes ([RR]: 1.35; 95% CI 1.02 - 1.78), vital capacity < or = 81% of the theoretical value ([RR]: 2.50; 95% CI 1.88 - 3.32), forced expiratory volume in 1 second < or = 72% of the theoretical value ([RR]: 2.02; 95% CI 1.55 - 2.72) and serum sodium level < or = 139 mmol/L ([RR]: 1.95; 95% CI 1.44 - 2.63) predicted CHF mortality. This model is able to identify elderly people at increased risk of death from CHF.

Oxidative stress and baroreflex sensitivity in healthy subjects and patients with mild-to-moderate hypertension

Decreased baroreflex sensitivity (BRS) is a prognostic marker in essential hypertension. Animal experiments suggest that decreased BRS is related to increased oxidative stress. Our study was aimed at testing whether oxidative stress, estimated by isoprostane 15-F(2t)-IsoP urinary levels, is correlated to BRS variation in healthy subjects as well as in patients suffering from essential hypertension. Urinary 15-F(2t)-IsoP levels and BRS were evaluated in two groups of subjects: healthy volunteers (n=64) and patients with untreated mild-to-moderate hypertension (n=33). Data were analysed in 61 and 31 subjects, respectively, BRS analysis being impossible in three and two subjects, respectively. 15-F(2t)-IsoP levels were measured using gas chromatography/mass spectrometry. BRS was measured using the sequence method [PS+/RR+ and PS-/RR-] and crossspectral analysis (CSP) (MF gain) at rest, lying down. No significant correlation was found between basal urinary 15-F(2t)-IsoP levels and BRS (sequence method and CSP) in either healthy controls or hypertensive patients. Our study shows that oxidative stress is not involved in interindividual variations of BRS in healthy subjects and patients suffering from mild-to-moderate hypertensionJournal of Human Hypertension (2004) 18, 517-521. doi:10.1038/sj.jhh.1001684 Published online 12 February 2004

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.

Pulse pressure responses to psychological tasks improve the prediction of left ventricular mass: 10 years of follow-up

OBJECTIVES

To examine the role of casual blood pressure measurements and blood pressure responses to psychological tasks in the prediction of future left ventricular mass index (LVMI), and to determine the importance of different components of blood pressure, and the predictive value of an individual's personal characteristics and antihypertensive medication on future LVMI.

METHODS

At baseline, blood pressure was recorded by casual measurements; during tests it was recorded by intra-arterial monitoring. The participants were healthy, untreated 35-45-year old men. Echocardiography data both at baseline and after 10 years of follow-up were available from 65 individuals, of whom 49 (75%) were not taking antihypertensive medication at follow-up. Those not taking antihypertensive medication were included in the prediction of LVMI (g/m2).

RESULTS

Baseline LVMI correlated significantly with future LVMI only among the 49 unmedicated individuals (r = 0.52, P < 0.0001). The predictive value of baseline LVMI on future LVMI among them (adjusted coefficient of determination = 0.26) was not improved by the inclusion of casual blood pressure. In contrast, blood pressure responses to the psychological tasks improved the prediction of future LVMI by 4-13%. Pulse pressure was the blood pressure variable that entered the final prediction models; the correlations with future LVMI were best for pulse pressure response to habituation task (r = 0.43, P < 0.05) and to relaxation (r = 0.37, P < 0.05).

CONCLUSIONS

To our knowledge, this is the longest prospective follow-up to show that blood pressure responses to psychological tasks improve the prediction of LVMI compared with casual blood pressure measurements. The pulse pressure, which reflects the properties of the arterial wall, is the most significant blood pressure variable in predicting future LVMI.

Pulsatile and steady 24-h blood pressure components as determinants of left ventricular mass in young and middle-aged essential hypertensives

In order to explore the relations between left ventricular mass (LVM) and the pulsatile (pulse pressure) and steady (mean pressure) components of the blood pressure (BP) curve, 304 young and middle-aged essential hypertensive patients were studied by means of 24-h ambulatory BP monitoring and echocardiography. In the overall study population, both the BP components showed significant correlations with LVM. These correlations were unevenly distributed in the subgroups of subjects younger and in those older than 50 years. While in this latter subgroup, in multivariate analysis, both 24-h mean BP (24-MBP) (beta = 0.27; P = 0.008) and 24-h pulse pressure (24-h PP) (beta = 0.23; P = 0.02) were associated with LVM, in the subset of younger hypertensives only 24-h MBP (beta = 0.21; P = 0.009) was related to LVM, independent of other covariates. The relations observed between 24-h PP and LVM in the entire study population and in the patients older than 50 years lost statistical significance when the effect of 24-h systolic blood pressure (24-h SBP) was taken into account, in a multiple regression model in which 24-h MBP was replaced by 24-h SBP. Our findings seem to suggest that the association of PP with LVM in middle-aged hypertensives may partially explain the increased cardiovascular risk, documented in subjects with high PP. However, this relation is not independent, but is mediated by SBP.

Lipid peroxidation is not increased in patients with untreated mild-to-moderate hypertension

In contrast with the huge amount of experimental data available, only few and somewhat unconvincing clinical studies support the hypothesis that oxidative stress is involved in the early stages of essential hypertension in humans. Isoprostanes are chemically stable lipid peroxidation products of arachidonic acid, the quantification of which provides a novel approach to the assessment of oxidative stress in vivo. The main objective of this study was to quantify the urinary levels of 15-F(2t)-IsoP in the early stages of essential hypertension, using gas chromatography/mass spectrometry, by comparing 30 patients with never-treated mild-to-moderate hypertension with 30 gender- and age-paired healthy controls. Urinary 15-F(2t)-IsoP levels were not significantly different in hypertensive patients (69+/-36 pmol/mmol creatinine) compared with controls (75+/-34 pmol/mmol creatinine, 95% confidence intervals on differences: -23 to 13). No significant correlation was found between basal urinary 15-F(2t)-IsoP levels and age, low-density lipoprotein cholesterol, glucose, clinical pulse pressure, carotid intima-media thickness, left ventricular mass index, or aortic pulse wave velocity. In conclusion, this study shows that lipid peroxidation is not increased in never-treated mild-to-moderate hypertension. This suggests that oxidative stress is not implicated in the pathogenesis of human essential hypertension, at least in the early stages.

Biochemical endothelial markers and cardiovascular remodeling in refractory arterial hypertension

BACKGROUND

Hypertension is the most important and well established risk factor for atherosclerosis. The vascular and cardiac remodeling present in refractory hypertensive patients are related to endothelial dysfunction, a key factor in early atherogenesis and cardiovascular disease. However the mechanistic relationship among biochemical endothelial function markers, cardiovascular remodeling, and refractory hypertension is unknown.

METHODS

We evaluated the left ventricular mass and function, carotid thickness, and plasma nitrate/nitrite (NO2/NO3), cyclic 3'-5'-guanosine monophosphate (cGMP), and thromboxane B2 (TXB2) levels in refractory hypertensive (RH; n = 20) and healthy (CONTROL; n = 20) subjects 22-65 years old. Carotid thickness, left ventricular mass index (LVMI), and left ventricular fraction ejection (LVFE) were estimated by duplex scan ultrasound. Nitrates/nitrites were assayed using the Griess reaction, and plasma cGMP and thromboxane B2 were determined by enzymatic immunoassay (EIA).

RESULTS

Left ventricular mass index was higher in the RH group (138 +/- 20 vs. 108 +/-17 g/m2, p < 0.001) but there was no significant difference in the ejection fraction (67 +/- 5% vs. 69 +/- 4%). Pulse pressure (61 +/- 9 mmHg vs. 46 +/- 10 mmHg) and carotid thickness (1.59 +/- 0.22m vs. 1.04 +/- 0.14mm) were significantly higher (p < 0.001) in RH patients whereas NO2/NO3, cGMP, and thromboxane B2 plasma concentrations were similar in bot groups.

CONCLUSION

There was no association between cardiovascular remodeling and the particular biochemical markers of endothelial function we assessed in refractory hypertensive patients.

Pulse pressure in tests improves the prediction of left ventricular mass: 10 years of follow-up

Literature does not agree with the usefulness of exercise blood pressure (BP) in predicting hypertension or target organ damage. In this prospective 10 years of follow-up, we evaluated if exaggerated BP responses to tests may improve the prediction of left ventricular mass index (LVMI). At baseline, BP was recorded by casual measurements, and during tests using intra-arterial monitoring. The subjects were 97 healthy, untreated 35- to 45-year-old-men (34 normotensive, 29 borderline hypertensive, and 34 mild hypertensive). At 10-year follow-up, echocardiography was performed to 86 (89%) of them. Subjects not taking antihypertensive medication (n = 66) were included in the prediction of LVMI(g m-2). Echocardiography data at baseline was available from 70 (72%) of the subjects, of whom 52 did not use antihypertensive medication at follow-up. Pulse pressure (PP) at supine test (r = 0.337, P = 0.006), PP at dynamic exercise last work load (r = 0.332, P = 0.006), and PP after dynamic exercise (r = 0.316, P = 0.010) were the best BP variables achieved in tests in predicting future LVMI of the 66 subjects. Casual BP did not significantly correlate with future LVMI. The best model in predicting LVMI included PP achieved after dynamic exercise, family history of hypertension, and body mass index (BMI) (adj.R2 = 0.207). Baseline LVMI correlated significantly with future LVMI only among the 52 unmedicated subjects (r = 0.508, P<0.0001). The predictive value of baseline LVMI on future LVMI among them (adj.R2 = 0.243) was best improved by PP achieved in supine test and age (adj.R2 = 0.350). In conclusion, BP measurements during tests improved the prediction of LVMI compared with casual BP. For the first time, the pulsatile component of BP in tests was found to be the most significant BP parameter in predicting future LVMI.

Assessment of outcomes other than systolic and diastolic blood pressure: pulse pressure, arterial stiffness and heart rate

In recent years, studies have shown that parameters derived from the arterial pressure wave other than systolic and diastolic blood pressure provide important information on cardiovascular status. Among these parameters, pulse pressure, arterial stiffness and heart rate have emerged as independent markers of cardiovascular risk in different populations. Although a number of studies have used casual measurements of these parameters in a clinic setting, others have focused on their assessment under ambulatory conditions. The pulse pressure represents the amplitude of the pressure wave signal (systolic minus diastolic blood pressure), higher pulse pressure values having been reported in patients possessing cardiovascular risk factors. Close associations between a high pulse pressure and several surrogate end-points have been described. Furthermore, epidemiological studies have shown that a high pulse pressure is an independent predictor of hard end-points in several populations. Arterial stiffness represents one of the major haemodynamic factors determining pulse pressure. Pulse wave velocity, measured from the initial upstroke of the pressure wave, constitutes an established index of arterial stiffness. Studies have reported stiffer arteries in patients with cardiovascular pathology even at an early stage of disease. Close correlations between arterial stiffness and several surrogate markers have been reported, and arterial stiffness and its changes have recently been shown to be an independent predictor of hard end-points in patients with a high cardiovascular risk. Methods to evaluate arterial stiffness under ambulatory conditions are emerging. Heart rate represents the frequency of the cyclical strain of the arterial wall, clinical studies having shown that ambulatory heart rate is correlated to several surrogate markers. A few epidemiological studies have analysed the value of ambulatory heart rate as an independent predictor of hard end-points, but their positive findings need to be confirmed. The analysis of the pressure wave thus allows the determination of several haemodynamic indices other than systolic and diastolic blood pressure. Pulse pressure, arterial stiffness and heart rate constitute other outcomes that may be useful as additional factors in risk assessment for future therapeutic decision-making.

Pulse pressure is the best predictor of future left ventricular mass and change in left ventricular mass: 10 years of follow-up

BACKGROUND

Ambulatory blood pressure correlates more closely with left ventricular mass (LVM) than casual blood pressure in cross-sectional studies, but prospective evidence is very limited.

OBJECTIVE

To evaluate the best predictors of LVM and change in LVM during 10 years of follow-up, in a prospective study.

METHODS

At baseline, blood pressure was recorded by casual measurements and 24 h intra-arterial ambulatory monitoring. The study participants were 97 healthy, untreated, 35-45-year-old men (34 normotensive, 29 borderline hypertensive, and 34 mildly hypertensive). At 10-year follow-up, echocardiography was performed in 86 (89%) of the men; echocardiographic data were available both at baseline and at follow-up from 70 (72%) of them. Individuals who were not receiving antihypertensive medication (n = 66) were included in the prediction of LVM index (LVMI), which was analysed as a continuous variable.

RESULTS

The blood pressure variables that were best in predicting the LVMI were: 24 h pulse pressure (r = 0.308, P = 0.012), night-time pulse pressure (r = 0.291, P = 0.018), daytime pulse pressure (r = 0.253, P = 0.041), and casual systolic blood pressure (r = 0.212, P = 0.088). The LVMI was best predicted by a model including 24 h pulse pressure, positive family history of hypertension, body mass index, and age (adjusted coefficients of determination (adj.R2) = 0.197; that for the casual blood pressure model was adj.R2 = 0.140). During the follow-up, LVMI increased by +7.5 g/m2 and +23 g/m2 in individuals receiving and not receiving antihypertensive medication, respectively (P = 0.015). The change in LVMI was best predicted by the change in casual pulse pressure and use of antihypertensive medication (adj.R2 = 0.102).

CONCLUSIONS

Ambulatory blood pressure improved the prediction of future LVMI compared with that obtained from casual measurements. To our knowledge, this is the longest prospective follow-up to show that pulse pressure is the most significant blood pressure parameter in predicting future LVMI and change in LVMI.

Carotid remodeling in essential hypertension: role of blood pressure, indexed parameters, and association with cardiac mass and aortic stiffness

The role of blood pressure on carotid remodeling, using no indexed and indexed parameters, was studied in essential hypertension. Carotid parameters were also compared to cardiac mass and aortic stiffness. Forty untreated hypertensive men had echocardiography, carotid ultrasonography and carotidfemoral pulse wave velocity measurements. Cross-sectional area index was associated essentially with the 24-hour systolic blood pressure whereas intima-media thickness was related especially to the 24-hour pulse pressure. Carotid intima-media thickness and cross-sectional area indexes were less related to blood pressure variables than non-indexed parameters. There is an independent association between 24-hour pulse pressure and left ventricular mass index and pulse wave velocity. To conclude, blood pressure, particularly pulse pressure, is associated with vascular and cardiac alterations. The indexation by the body surface area do not provide any additional information in the association between carotid and blood pressure parameters.