Estrogens, progestins, and heart disease: can endothelial function divine the benefit?

Prevalence and predictors of coronary artery disease in adults with Kawasaki disease

BACKGROUND

Accelerated coronary atherosclerosis in patients with Kawasaki disease, in conjunction with coronary artery aneurysm and stenosis that characterise this disease, are potential risk factors for developing coronary artery disease in young adults. We aimed to determine the prevalence and predictors of coronary artery disease in adult patients with Kawasaki disease.

METHODS

All patients aged 18-55 years of age diagnosed with Kawasaki disease were sampled from Nationwide Inpatient Sample database using International Classification of Diseases 9th revision (ICD 9 code 446.1) from 2009 to 2010. Demographics, prevalence of coronary artery disease, and other traditional risk factors in adult patients with Kawasaki disease were analysed using ICD 9 codes.

RESULTS

The prevalence of Kawasaki disease among adults was 0.0005% (n=215) of all in-hospital admissions in United States. The mean age was 27.3 years with women (27.6 years) older than men (27.1 years). Traditional risk factors were hypertension (21%), hyperlipidaemia (15.6%), diabetes (11.5%), tobacco use (8.8%), and obesity (8.8%), with no significant difference between men and women. Coronary artery disease (32.4%), however, was more prevalent in men (44.7%) than in women (12.1%; p=0.03). In multivariate regression analysis, after adjusting for demographics and traditional risk factors, hypertension (OR=13.2, p=0.03) was an independent risk factor of coronary artery disease.

CONCLUSION

There was increased preponderance of coronary artery disease in men with Kawasaki disease. On multivariate analysis, hypertension was found to be the only independent predictor of coronary artery disease in this population after adjusting for other risk factors.

Associations of Depressive Symptoms and Brachial Artery Reactivity among Police Officers

Objectives

Mental health has been shown to be linked with certain underlying physiological mechanisms. The objective of this cross sectional study was to investigate the relationship between depressive symptoms and brachial artery reactivity (BAR) in an understudied population: police officers.

Methods

Participants were 351 police officers who were clinically examined in the Buffalo Cardio-Metabolic Police Stress (BCOPS) study. BAR was performed using standard B-Mode ultrasound procedures. Depressive symptoms were measured using the Center for Epidemiological Studies Depression (CES-D) scale. Mean values of the difference between the baseline and maximum diameters of the brachial artery were determined across three categories of CES-D score using the analysis of variance and the analysis of covariance. p-values for linear trends were obtained from linear regression models.

Results

The mean age (± standard deviation) of all officers was 40.9 ± 7.2 years. Women had a slightly higher mean CES-D score than men (8.9 ± 8.9 vs. 7.4 ± 6.4) and a slightly higher percentage increase of BAR than men (6.90 vs. 5.26%). Smoking status significantly modified the associations between depressive symptoms and BAR. Among current smokers, mean absolute values of BAR significantly decreased as depressive symptoms increased after adjustment for age, gender, race/ethnicity, hypertension, and diabetes; the multivariate-adjusted p-values were 0.033 (absolute) and 0.040 (%). Associations between depressive symptoms and BAR were not statistically significant among former smokers or never smokers.

Conclusion

Depressive symptoms were inversely associated with BAR among police officers who were current smokers and together may be considered a risk factor for cardiovascular disease among police officers. Further prospective research is warranted.

Endothelial function, a biomarker of subclinical cardiovascular disease, in urban police officers

OBJECTIVE

Police officers were hypothesized to have decreased endothelial function, measured by brachial artery flow-mediated dilation (FMD).

METHODS

We compared FMD in police officers (n = 261) and a population sample of men and women (n = 229), all from the same geographical region and free of clinical cardiovascular disease (CVD).

RESULTS

Compared with the population sample, police officers had significantly increased age-adjusted CVD risk factors (systolic and diastolic blood pressure, total cholesterol, smoking prevalence, and alcohol consumption). Police officers exhibited lower mean FMD after adjustment for age, gender, and traditional CVD risk factors among those aged 55 years or younger (%dilation: police = 5.49%, population = 6.49%; P = 0.04).

CONCLUSIONS

Police officers exhibited decreased endothelial function (lower FMD) compared with the civilian sample, which was not fully explained by traditional CVD risk factors, suggesting that other pathways may contribute to increased CVD risk in law enforcement work.

Brachial artery ultrasound: a noninvasive tool in the assessment of triglyceride-rich lipoproteins

In recent years, endothelial dysfunction has been identified as an early feature of atherosclerosis. Endothelial function can be measured noninvasively by using brachial artery ultrasound. A variety of factors associated with atherosclerosis also impair endothelial function. Some of these factors are lipoproteins such as various forms of low-density lipoproteins, postprandial chylomicron remnants, fasting triglyceride-rich particles, and free fatty acids. A high-fat diet also has an adverse effect on endothelial function. Several interventions can improve endothelial function and, at the same time, reduce cardiovascular events. Measuring endothelial function may eventually serve as a useful index to determine an individual's risk for coronary artery disease.

A comparison of brachial artery flow-mediated vasodilation using upper and lower arm arterial occlusion in subjects with and without coronary risk factors

BACKGROUND

The ultrasound assessment of brachial artery flow-mediated vasodilation provides a noninvasive means for measuring endothelial function. The test is performed using either upper or lower arm blood pressure cuff arterial occlusion to induce hyperemia. Upper arm occlusion produces a greater hyperemic stimulus. Brachial artery flow-mediated vasodilation is abnormal in the presence of coronary risk factors.

HYPOTHESIS

The study sought to compare the ability of the upper and lower arm occlusion techniques to differentiate endothelial function in subjects with and without risk factors.

METHODS

We measured brachial artery flow-mediated vasodilation in 20 subjects, 10 without and 10 with a single risk factor (hypertension, hypercholesterolemia, or cigarette smoking) using both the upper and lower arm occlusion techniques (5 min blood pressure cuff occlusion). Using 11 MHz ultrasound, Doppler blood flow velocities were measured before and immediately after cuff deflation. Brachial artery vasodilation was measured 1 min after cuff deflation, compared with baseline, and expressed as a percent increase.

RESULTS

The immediately postocclusion hyperemia (% increase in flow) was significantly greater (p < 0.01) using the upper versus the lower arm technique in both the normal (530 +/- 152 vs. 383 +/- 51%) and the risk factor (583 +/- 153 vs. 409 +/- 114%) groups. Flow-mediated vasodilation was significantly greater (p < 0.01) using the upper arm versus the lower arm occlusion technique in both the normal (13.4 +/- 5.3 vs. 5.6 +/- 3.4%) and risk factor (7.9 +/- 3.6 vs. 3.9 +/- 2.2%) groups. Vasodilation was significantly greater (p < 0.01) in the normal subjects than in the risk factor subjects (13.4 +/- 5.3 vs. 7.9 +/- 3.6%) using the upper arm technique, but was not statistically different in the two groups using the lower arm technique.

CONCLUSIONS

Our study demonstrates that upper arm compared with lower arm cuff occlusion undertaken to induce hyperemia for the assessment of brachial artery flow-mediated vasodilation results in significantly greater hyperemia and vasodilation. Flow-mediated vasodilation obtained using the upper arm technique better separates subjects with and without coronary risk factors.

Review: Endothelial dysfunction: A potential tool in gender related cardiovascular disease

The overwhelming importance of distinctive cardiovascular disease profile in women has stimulated enormous efforts to disclose its cause. In this review, we discuss vascular endothelium as a potential phenotypic marker for the genetic difference. As it is a potentially modifiable factor for cardiovascular disease, every effort should be made to detect it, either directly or indirectly, at the earliest in females who are at risk, so that the future cardiovascular events might be prevented.

Effect of hyperbaric oxygen on flow-mediated vasodilation: an ultrasound study

OBJECTIVE

The purpose of this study was to investigate the effect of hyperbaric oxygen (HBO) treatment on flow-mediated vasodilation (FMD) by ultrasound examination.

METHODS

We studied 14 young patients without cardiovascular problems who underwent HBO treatment. The indications for HBO treatment were osteomyelitis (n = 8), Crohn disease (n = 2), perianal abscesses (n = 2), lingual artery embolization (n = 1), and aseptic necrosis (n = 1). The ultrasound evaluation for FMD was performed before HBO treatment, after 1 session of HBO treatment, and after 10 sessions of HBO treatment. The right brachial artery FMD response was evaluated by the mean of the baseline right brachial artery diameter, absolute change in the diameter before and after cuff inflation/deflation, and percent change in the diameter.

RESULTS

Statistical analysis showed a significant change in the preinflation right brachial artery diameter before (mean +/- SD, 3.6 +/- 0.54 mm) and after (3.76 +/- 0.56 mm) 10 sessions of HBO treatment (P < .05). The absolute changes in the right brachial artery diameter before and after cuff inflation/deflation (0.36 +/- 0.2 mm before HBO treatment, 0.37 +/- 0.22 mm after 1 session of HBO treatment, and 0.38 +/- 0.21 mm after 10 sessions) and percent change in FMD (10% +/- 5.8% before HBO treatment, 10.6% +/- 7.5% after 1 session of HBO treatment, and 10.6% +/- 7.7% after 10 sessions) after induction of a hyperemic response by cuff inflation were not statistically significant (P > .05).

CONCLUSIONS

Hyperbaric oxygen treatment did not have an immediate effect on FMD (absolute change in the right brachial artery diameter after cuff inflation/deflation); however, the right brachial artery diameter increased after 10 sessions of HBO treatment. This may suggest chronic stress on the vascular endothelium after HBO.

Noninvasive assessment of preclinical atherosclerosis

Initially considered as a semipermeable barrier separating lumen from vessel wall, the endothelium is now recognised as a complex endocrine organ responsible for a variety of physiological processes vital for vascular homeostasis. These include the regulation of vascular tone, luminal diameter, and blood flow; hemostasis and thrombolysis; platelet and leucocyte vessel-wall interactions; the regulation of vascular permeability; and tissue growth and remodelling. The endothelium modulates arterial stiffness, which precedes overt atherosclerosis and is an independent predictor of cardiovascular events. Unsurprisingly, dysfunction of the endothelium may be considered as an early and potentially reversible step in the process of atherogenesis and numerous methods have been developed to assess endothelial status and large artery stiffness. Methodology includes flow-mediated dilatation of the brachial artery, assessment of coronary flow reserve, carotid intimamedia thickness, pulse wave analysis, pulse wave velocity, and plethysmography. This review outlines the various modalities, indications, and limitations of available methods to assess arterial dysfunction and vascular risk.

The Cardiovascular Effects of Selective Estrogen Receptor Modulators

Coronary artery disease (CAD) is the main contributor of mortality among postmenopausal women. Menopause-associated estrogen deficiency has both metabolic and vascular consequences that increase the risk for CAD. Hormone therapy (HT) has been reported to have a beneficial effect on metabolic and vascular factors influencing the incidence of CAD. Although observational studies have reported that HT reduces significantly the risk for CAD, randomized clinical trials (WHI, HERS, ERA) have questioned the efficacy of HT in primary and secondary CAD prevention despite confirming the lipid-lowering effect of HT. In the aftermath of the WHI, increased interest has been given to the action of selective estrogen receptor modulators (SERMs) and their effect on the cardiovascular system. The chemical structure of SERMs, either triphenylethilyn (tamoxifen) or benzothiophene (raloxifene) derivatives, differs from that of estrogens. SERMs are nonsteroidal molecules that bind, with high affinity, to the ER. SERMs induce conformational changes to the ligand-binding domain of the ER that modulate the ability of the ER to interact with coregulator proteins. The relative balance of coregulators within a cell determines the transcriptional activity of the receptor-ligand complex. SERMs therefore may express an estrogen-agonist or estrogen-antagonist effect depending on the tissue targeted. SERMs express variable effects on the metabolic and vascular factors influencing the incidence of CAD. SERMs have been reported to modulate favorably the lipid-lipoprotein profile. Toremifene expresses the most beneficial effect followed by tamoxifene and raloxifene, while ospexifene and HMR-3339 have the least effect and may even increase triglycerides. Raloxifene and tamoxifene decrease serum homocysteine levels and C-reactive proteins (CRP), which are both markers of CAD risk. Raloxifene has been reported to increase the nitric oxide (NO)-endothelin (ET)-1 ratio and, thus, contribute to proper endothelial function and vasodilation. Toremifene has no effect on the NO-ET-1 ratio. Finally, raloxifene decreases the vascular cell adhesion molecules and the inflammatory cytokines TNF-alpha and IL-6. Of the SERMs, raloxifene has had the most extensive evaluation regarding the effect on the vascular wall of endothelium. Although not confirmed by large clinical trials, raloxifene has been reported to have an effect on the cohesion of the intercellular junction (VE-cadherin) and the synthesis-degradation of extracellular matrix (MMP-2). The Multiple Outcomes Raloxifene Evaluation (MORE) study has reported that raloxifene may have a cardioprotective effect when administered to postmenopausal women at high risk for CAD disease.

Endothelial dysfunction, intima–media thickness and coronary reserve in relation to risk factors and Framingham score in patients without clinical atherosclerosis

BACKGROUND

Endothelial dysfunction, decreased coronary flow reserve (CFR) and increased intima-media thickness (IMT) are related to atherosclerosis and can be assessed non-invasively by echography.

OBJECTIVES

In order to describe the relationship between these parameters and with cardiovascular risk, this study investigated them simultaneously in patients without clinical atherosclerosis.

METHODS

A total of 106 subjects were studied, 91 with and 15 without cardiovascular risk factors. Cardiovascular disease was excluded in all cases. Doppler ultrasound was used to analyse endothelium-dependent vascular dilation in the brachial artery, IMT in the common carotid artery and CFR in the left anterior artery.

RESULTS

Patients with cardiovascular risk factors had impaired flow-mediated dilation (FMD; 3.7 +/- 3.2 versus 11.6 +/- 4.4%, P = 0.000); greater IMT (0.89 +/- 0.3 versus 0.56 +/- 0.14 mm, P = 0.000) and lower CFR (2.7 +/- 0.9 versus 4 +/- 1.2, P = 0.000). Correlation was found between IMT and FMD r = -0.240, (P = 0.013), IMT and CFR, r = -0.384 (P = 0.000), and between FMD and CFR of r = 0.289 (P = 0.007). All patients with IMT greater than 1 mm showed depressed FMD, most of them with low values of CFR, but patients with reduced FMD or CFR did not necessarily show increased IMT. There was a significant correlation between the three parameters and the Framingham risk score. Multiple linear regression analysis showed that IMT was the only factor related to the Framingham score.

CONCLUSION

In patients without clinical atherosclerotic disease, cardiovascular risk factors are associated with impaired FMD, CFR and increased IMT. Even though a correlation between these changes was found, they showed different dependence on cardiovascular risk factors and with global risk, IMT being the best correlated with the Framingham score.

Comparison of angiographic findings among postmenopausal women using unopposed estrogen, estrogen/progestin combinations, and nonusers

Studies of the effects of menopausal hormone therapy on coronary artery disease (CAD) in postmenopausal women have provided contradictory results. Although recent experimental studies have revealed no beneficial effect of combination therapy with estrogen (E) and progesterone (P), the effect of monotherapy with E remains unknown. We retrospectively examined the medical records of 843 consecutive women aged > or =55 years who underwent their first cardiac catheterization between January 1996 and December 1998. We compared the presence and severity of CAD, defined as > or =1 diseased coronary vessel (with stenosis > or =50%), in women who only took E, E+P, or no menopausal hormone therapy. In all, 210 women (33%) took hormones, of whom 47 (22%) used E+P and 163 (78%) used E only. Women who used any hormones tended to be healthier than nonusers, but E+P users had a lower prevalence of risk factors and co-morbidities than E users. In unadjusted analyses, both the E and E+P groups were significantly less likely to have CAD than nonusers (relative risk [RR] 0.71, 95% confidence interval [CI] 0.58 to 0.84 for the E group; RR 0.76, 95% CI 0.54 to 0.99 for the E+P group). Demographic factors, CAD risk factors, co-morbidities, and primary prevention medication use explained the association between E+P and the presence of CAD (RR 1.14, 95% CI 0.74 to 1.39). In contrast, adjustment for these factors had a minimal effect on the association between E and CAD compared with nonusers (RR 0.79, 95% CI 0.59 to 0.98). Thus, the apparent protective effect of combination menopausal hormone therapy with E+P on CAD is due to differences in other patient characteristics. In contrast, unopposed E therapy may have a protective effect on CAD.

[Endothelial dysfunction and intima-media thickness in relation to cardiovascular risk factors in patients without clinical manifestations of atherosclerosis]

INTRODUCTION

Endothelial dysfunction and increased intima-media thickness are early findings in the development of atherosclerosis that can be assessed non-invasively by echography. The aim of this study was to investigate endothelial function and intima-media thickness, and the relation between these processes and cardiovascular risk factors in patients without clinical atherosclerosis.

PATIENTS AND METHOD

Fifty-two subjects were studied, 39 with one or more cardiovascular risk factors and 13 with none. Vascular echography was performed to analyze endothelium-dependent vascular dilatation in the brachial artery and intima-media thickness in the common carotid artery.

RESULTS

Compared to patients without risk factors, patients with cardiovascular risk factors more frequently had impaired vascular dilatation after ischemia, 11.98 4.61% vs 2.77 2.57%, (P<.0.001; mean difference = 9.21%, 95% CI of the difference 6.33-12.07%) and a greater intima-media thickness, 0.085 0.024% vs 0.057 0.014 cm (P < 0.0001; mean difference = 0.028 cm, 95% CI of the difference, 0.017-0.04 cm). There was a significant negative correlation between intimal-media thickness and endothelial dysfunction (r = -0.357; P<0.01). Linear regression analysis showed that intima-media thickness was independently related to age and the presence of hypertension, while endothelial function was related only with the presence of hypertension, smoking, and hyperlipoproteinemia.

CONCLUSIONS

In patients without clinical atherosclerotic disease, cardiovascular risk factors were associated with impaired endothelial function and increased intima-media thickness. There was a negative correlation between endothelial-dependent vascular dilatation and intima-media thickness.

Predictive value of noninvasively determined endothelial dysfunction for long-term cardiovascular events in patients with peripheral vascular disease

OBJECTIVES

The goal of this study was to prospectively examine the long-term predictive value of brachial-artery endothelial dysfunction for future cardiovascular events.

BACKGROUND

Brachial-artery endothelial function is impaired in individuals with atherosclerosis and coronary risk factors. The prospective relation between endothelial function determined by brachial-artery ultrasound and long-term cardiovascular risk is unknown.

METHODS

We examined brachial-artery endothelial function using ultrasound in 199 patients with peripheral arterial disease before elective vascular surgery. Patients were prospectively followed with an average follow-up of 1.2 years after surgery.

RESULTS

Thirty-five patients had an event during follow-up, including cardiac death (5 patients), myocardial infarction (17 patients), unstable angina (10 patients), or stroke (3 patients). Preoperative endothelium-dependent flow-mediated dilation (FMD) was significantly lower in patients with an event (4.4 +/- 2.8%) compared with those without an event (7.0 +/- 4.9%, p < 0.001), whereas endothelium-independent vasodilation to nitroglycerin was similar in both groups. In a Cox proportional-hazards model, independent predictors of events included age (p = 0.003), more invasive surgery (surgery other than carotid endarterectomy, p = 0.02), and impaired brachial-artery endothelial function (p = 0.002). Risk was approximately nine-fold higher in patients with FMD <8.1% (lower two tertiles) compared with those in the upper tertile (odds ratio 9.5; 95% confidence interval 2.3 to 40).

CONCLUSIONS

Impaired brachial-artery endothelial function independently predicts long-term cardiovascular events in patients with peripheral arterial disease. The findings suggest that noninvasive assessment of endothelial function using brachial-artery FMD may serve as a surrogate end point for cardiovascular risk.

Noninvasive Studies of Coronary and Peripheral Arterial Blood-flow

Noninvasive vascular imaging may identify the high-risk, asymptomatic atherosclerotic patient who will substantially benefit from aggressive preventive therapies. Endothelium is a key player in the early stages of atherogenesis. Positron emission tomography (PET) and ultrasound-measured brachial artery vasoreactivity have emerged as potentially useful tools for the identification of endothelial dysfunction and, as such, early atherosclerosis. Both have been used successfully to demonstrate the association between endothelial dysfunction and established coronary artery disease risk factors, as well as clinically evident coronary artery disease. Abnormal coronary endothelial function recently has been associated with poor clinical outcomes in long-term follow-up studies. Given the close association between endothelial function in the coronary and peripheral circulation, there is particular promise for the validation of brachial artery vasoreactivity as a clinically useful tool. Finally, surveillance of endothelial function with these techniques may prove helpful in guiding aggressiveness of antiatherosclerotic therapy and effectiveness of new regimens.

Isoflavone supplementation and endothelial function in menopausal women

OBJECTIVE

Despite strong observational evidence for a beneficial role of oestrogen in cardiovascular disease, recent trial results suggest that hormone replacement therapy (HRT) may have adverse effects in menopausal women with established coronary heart disease. Isoflavones are oestrogen analogues found in plants with oestrogen-like properties and, because of a favourable side-effect profile, may be ideal alternatives to HRT with respect to cardiovascular benefits. Endothelial function is a marker of cardiovascular health. We aimed to determine the effect of isoflavones on endothelial function using the brachial artery reactivity test.

DESIGN AND MEASUREMENTS

Twenty-nine healthy menopausal women underwent entry and exit brachial artery reactivity testing following randomization to 2 weeks of an oral soy isoflavone concentrate containing 80 mg of soy isoflavones (Archer Daniel Midland Inc., IL, USA) or placebo.

RESULTS

At study exit, there was no difference between placebo and isoflavone groups with respect to flow-mediated dilation (%FMD(max)), change (entry to exit) in %FMD(max) or response to nitroglycerine (%TNG). Subgroup analyses assessing lipid and oestrogen effects did not produce any significant results.

CONCLUSIONS

These results suggest that short-term oral isoflavone supplements do not improve endothelial function in healthy menopausal women.

Effect of endurance training on coronary artery size and function in healthy men: an invasive followup study

In eight healthy male volunteers (cardiologists; age 36 +/- 5 yr), bicycle spiroergometry, Doppler echocardiography, and quantitative coronary angiography with intracoronary Doppler measurements before and after completion of a physical endurance exercise program of >5 mo duration were performed. Maximum oxygen uptake increased from 46 +/- 6 to 54 +/- 5 ml x kg(-1) x min(-1) (P = 0.04), maximum ergometric workload changed from 3.8 +/- 0.3 to 4.4 +/- 0.3 W/kg (P = 0.001), and left ventricular mass index increased from 82 +/- 18 to 108 +/- 29 g/m(2) (P = 0.001). The right, left main, and left anterior descending coronary artery cross-sectional area increased significantly in response to exercise. Before versus at the end of the exercise program, flow-induced left anterior descending coronary artery cross-sectional area was 10.1 +/- 3.5 and 11.0 +/- 3.9 mm(2), respectively (P = 0.03), nitroglycerin-induced left coronary calibers increased significantly, and coronary flow velocity reserve changed from 3.8 +/- 0.8 to 4.5 +/- 0.7 (P = 0.001). Left coronary artery correlated significantly with ventricular mass and maximum oxygen uptake, and coronary flow velocity reserve was significantly associated with maximum workload.

Conjugated estrogen administration improves common carotid artery elastic properties in normotensive postmenopausal women

BACKGROUND

Various vascular effects of estrogens have been proposed to explain further the beneficial effect of replacement therapy in cardiovascular events.

HYPOTHESIS

The study was undertaken to assess the effect of conjugated estrogen on the elastic properties of the large arteries in normotensive, healthy, postmenopausal women.

METHODS

Toward this end, we investigated the acute effect of conjugated estrogen on the elastic properties of the common carotid artery (CCA) in 20 normotensive, healthy, postmenopausal women (age 54+/-3 years) at baseline and 20 min after the intravenous administration of 1.25 mg conjugated estrogens. The CCA distensibility was derived by a combination of surface ultrasonographic data and simultaneous blood pressure measurements at the brachial artery. The carotid pulsatility index, a measure of brain impedance, was determined electronically by tracing the CCA Doppler waveform.

RESULTS

At baseline, CCA distensibility had a negative correlation with both patients' age and time since menopause (r = -0.57 and r = -0.48, p < 0.05 for both cases). After estrogen administration, estradiol and estrone plasma levels were restored to the range of usual premenopausal values. Estrogen induced a significant increase in CCA distensibility by 0.92+/-0.005 dyne(-1) x cm2 x 10(-6) (from 2.03 to 2.95 dyne(-1) x cm2 x 10(-6)) and a significant reduction in CCA pulsatility index by 0.24+/-0.06, (from 2.17 to 1.93) (p < 0.001 for both cases). The improvement in CCA distensibility had a negative correlation with both patients' age and time since menopause (r= -0.46 and r = -0.44, respectively, p < 0.05 for both cases).

CONCLUSIONS

Acute conjugated estrogen administration induced an improvement in CCA elasticity and a reduction in brain impedance in normotensive, postmenopausal women. As the age of women and the time since menopause increased, the improvement in carotid distensibility decreased in such selected subjects.

Guidelines for the ultrasound assessment of endothelial-dependent flow-mediated vasodilation of the brachial artery: a report of the International Brachial Artery Reactivity Task Force

Endothelial function is thought to be an important factor in the pathogenesis of atherosclerosis, hypertension and heart failure. In the 1990s, high-frequency ultrasonographic imaging of the brachial artery to assess endothelium-dependent flow-mediated vasodilation (FMD) was developed. The technique provokes the release of nitric oxide, resulting in vasodilation that can be quantitated as an index of vasomotor function. The noninvasive nature of the technique allows repeated measurements over time to study the effectiveness of various interventions that may affect vascular health. However, despite its widespread use, there are technical and interpretive limitations of this technique. State-of-the-art information is presented and insights are provided into the strengths and limitations of high-resolution ultrasonography of the brachial artery to evaluate vasomotor function, with guidelines for its research application in the study of endothelial physiology.

Hormone replacement therapy and endothelial function. Results of a randomized controlled trial in healthy postmenopausal women

OBJECTIVE

To compare the effects of 3 months treatment with tibolone (a single entity synthetic steroid hormone with estrogenic, progestanic and androgenic activities), or continuous combined conjugated equine estrogens (CEE) plus medroxyprogesterone acetate (MPA), with placebo, on endothelial function.

DESIGN

A single center, randomized, double-blind, placebo-controlled study.

SETTING

Research center as part of the University Medical Center Utrecht.

SUBJECTS

One hundred and five healthy postmenopausal women, sampled from the general population.

INTERVENTIONS

Three months treatment with tibolone or CEE+MPA or placebo.

MAIN OUTCOME MEASURE

At baseline and after 3 months, endothelial function was assessed non-invasively by measuring percent lumen diameter change in the brachial artery after reactive hyperemia and sublingual nitroglycerine spray.

RESULTS

Results are presented as mean differences between treatment groups of endothelium dependent flow mediated dilatation (fmd) and endothelium independent nitroglycerine induced dilatation with 95% confidence intervals (95% CI). After treatment, there was a significant difference in mean fmd between the CEE+MPA group and the placebo group of 2.5% (95% CI: 0.3-4.6) while the tibolone group and the placebo group did not differ significantly (0.6%; 95% CI: 1.6-2.8). Nitroglycerine induced dilatation did not differ significantly between the groups.

CONCLUSIONS

Hormone replacement therapy with CEE+MPA for 3 months increases endothelium dependent fmd of the brachial artery in healthy postmenopausal women. Tibolone did not alter fmd. The clinical significance of this improvement in fmd for cardiovascular disease risk needs to be established.

The postprandial effect of components of the Mediterranean diet on endothelial function

OBJECTIVES

This study investigated the postprandial effect of components of the Mediterranean diet on endothelial function, which may be an atherogenic factor.

BACKGROUND

The Mediterranean diet, containing olive oil, pasta, fruits, vegetables, fish, and wine, is associated with an unexpectedly low rate of cardiovascular events. The Lyon Diet Heart Study found that a Mediterranean diet, which substituted omega-3-fatty-acid-enriched canola oil for the traditionally consumed omega-9 fatty-acid-rich olive oil, reduced cardiovascular events.

METHODS

We fed 10 healthy, normolipidemic subjects five meals containing 900 kcal and 50 g fat. Three meals contained different fat sources: olive oil, canola oil, and salmon. Two olive oil meals also contained antioxidant vitamins (C and E) or foods (balsamic vinegar and salad). We measured serum lipoproteins and glucose and brachial artery flow-mediated vasodilation (FMD), an index of endothelial function, before and 3 h after each meal.

RESULTS

All five meals significantly raised serum triglycerides, but did not change other lipoproteins or glucose 3 h postprandially. The olive oil meal reduced FMD 31% (14.3 +/- 4.2% to 9.9 +/- 4.5%, p = 0.008). An inverse correlation was observed between postprandial changes in serum triglycerides and FMD (r = -0.47, p < 0.05). The remaining four meals did not significantly reduce FMD.

CONCLUSIONS

In terms of their postprandial effect on endothelial function, the beneficial components of the Mediterranean and Lyon Diet Heart Study diets appear to be antioxidant-rich foods, including vegetables, fruits, and their derivatives such as vinegar, and omega-3-rich fish and canola oils.

Prevention of coronary heart disease. Part II. Secondary prevention, detection of subclinical disease, and emerging risk factors

The prevention of CHD should be a major priority among primary care physicians and subspecialists who have any dealing with the cardiovascular system. There is ample evidence from epidemiologic studies for the impact of specific risk factors on CHD events. There is also ample evidence from observational studies and clinical trials that interventions of lifestyle and pharmacologic therapy can decrease morbidity and mortality from CHD before or after the first event. It behooves the physician who wishes to practice good medicine to understand the pathophysiologic roles of the risk factors and the evidence from epidemiologic studies and clinical trials for their association with cardiovascular disease. It is important to determine the efficacy of interventions, both lifestyle and pharmacologic, in modifying CHD risk. To be effective in doing so, the practicing physician has to have the motivation to determine target goals for risk factor modification in each patient, to understand the patient's own motivations in modifying risk factors, and to define clearly with the patient the expectations of such interventions. Although there are guidelines for risk factor modification in modification of cholesterol and in hypertension, the periodic renewal of these guidelines reflects the changing concepts of risk and its modification. A cardiovascular risk factor intervention categorization is presented in Table 12. The physician must be convinced that such intervention is beneficial to the patient, cost-effective, and thus fulfills the expectations of medical practice. The practice of medicine in the evaluation and treatment of coronary heart disease has always been challenging and stimulating. The prevention of CAD disease should ultimately provide the greatest accomplishment.

Treatment of stable angina

Severe atherosclerotic narrowing of one or more coronary arteries is responsible for myocardial ischemia and angina pectoris in most patients with stable angina pectoris. The coronary arteries of patients with stable angina also contain many nonobstructive plaques, which are prone to fissures or rupture resulting in presentation of acute coronary syndromes (unstable angina, myocardial infarction, sudden ischemic death). In addition to symptomatic relief of symptoms and an increase in angina-free walking time with antianginal drugs or revascularization procedures, the recent emphasis of treatment has been to reduce adverse clinical outcomes (coronary death and myocardial infarction). The role of smoking cessation, aspirin, treatment of elevated lipids, and treatment of high blood pressure in all patients and of beta-blockers and angiotensin-converting enzyme inhibitors in patients with diminished systolic left ventricular systolic function in reducing adverse outcomes has been well established. What is unknown, however, is whether any anti-anginal drugs (beta-blockers, long-acting nitrates, calcium channel blockers) effect adverse outcomes in patients with stable angina pectoris. Recent trials evaluated the usefulness of suppression of ambulatory ischemia in patients with stable angina pectoris, but it remains to be established whether suppression of ambulatory myocardial ischemia with antianginal agents or revascularization therapy is superior to pharmacologic therapy targeting symptom relief. Patients who have refractory angina despite optimal medical treatment and are not candidates for revascularization procedures may be candidates for newer techniques of transmyocardial revascularization, enhanced external counterpulsation, spinal cord stimulation, or sympathectomy. The usefulness of these techniques, however, needs to be confirmed in large randomized clinical trials.

Hormone and nonhormone therapy for the maintenance of postmenopausal health: the need for randomized controlled trials of estrogen and raloxifene

Multiple health benefits have been postulated for the long-term use of hormone therapy in postmenopausal women, most notably for prevention of osteoporotic fractures and coronary heart disease, as well as several risks, including cancer of the breast and uterus and venous thromboembolism. Cardiovascular disease is the most common cause of death among postmenopausal women. If real, the reduction in risk of coronary heart disease by hormone use suggested by observational studies would likely outweigh the risks. The decision to initiate and maintain hormone therapy is complicated by uncertainties about estrogen's true benefits and risks. Raloxifene, a selective estrogen receptor modulator (SERM), appears to have many of the benefits of estrogen without the cancer risks. It is not known if SERMs can provide significant cardiovascular protection. This article reviews the relation of use of postmenopausal hormones and raloxifene to women's health and addresses the need for large randomized trials to quantify the effect of both postmenopausal estrogen and raloxifene on cardiovascular health.