HMG CoA reductase inhibitors are related to improved systemic endothelial function in coronary artery disease

Statins Mitigate Stress-Related Vascular Aging and Atherosclerosis in apoE-Deficient Mice Fed High Fat-Diet: The Role of Glucagon-Like Peptide-1/Adiponectin Axis

Objectives

Exposure to chronic psychosocial stress is a risk factor for atherosclerotic cardiovascular diseases. Given that the 3-hydroxy-3-methylglutaryl-coenzyme reductase inhibitor statins prevent atherogenesis, we evaluated whether pitavastatin prevents chronic stress- and high fat diet-induced vascular senescence and atherogenesis in apolipoprotein E-deficient (ApoE^–/–) mice, with a special focus on glucagon-like peptide-1 (GLP-1)/adiponectin (APN) axis.

Methods and Results

6-week-old ApoE^–/– mice loaded a high-fat diet were randomly assigned into non-stress (n = 12) and stress (n = 13) groups for 12 weeks. Non-stress control mice were left undisturbed. Chronic stress accelerated high fat diet-induce arterial senescence and atherosclerotic plaque growth. The chronic stress lowered the levels of circulating GLP-1 as well as adipose and plasma APN. As compared with the stress alone mice, the pitavastatin-treated mice had reduced macrophage infiltration, elastin fragments, and increased plaque collagen volume, and lowered levels of osteopontin, toll-like receptor-2/-4, macrophage chemoattractant protein-1, C-X-C chemokine receptor-4, p47^phox, p47^phox, gp91^phox, cathepsins S, p16, and p21, mRNAs and/or proteins. Pitavastatin increased plasma GLP-1 and APN levels and suppressed matrix metalloproteinase-2/-9 gene expressions and activities in the aortas. Finally, the protective effect of pitavastatin was abrogated by APN blocking.

Conclusion

These findings suggested that the pitavastatin-mediated pleiotropic vasculoprotective effects are likely attributable, at least in part, to the elevation of GLP-1 and APN levels and the inhibition of diet-induced plaque inflammation, oxidative stress, and proteolysis in ApoE^–/– mice received chronic stress conditions.

Elevated Serum Non-HDL (High-Density Lipoprotein) Cholesterol and Triglyceride Levels as Residual Risks for Myocardial Infarction Recurrence Under Statin Treatment

Objective- Secondary prevention for recurrent myocardial infarction (MI) is one of the most important therapeutic goals in patients with old MI (OMI). Although statins are widely used for this purpose, there remains considerable residual risk even after LDL (low-density lipoprotein cholesterol) is well controlled by statins. Approach and Results- We examined clinical impacts of nHDL (nonhigh-density lipoprotein cholesterol) and its major components triglyceride and LDL as residual risks for acute MI recurrence, using the database of our CHART (Chronic Heart Failure Analysis and Registry in the Tohoku District)-2 Study, the largest-scale cohort study of cardiovascular patients in Japan. We enrolled 1843 consecutive old MI patients treated with statins (mean age 67.3 years, male 19.2%) in the CHART-2 Study. The incidence of recurrent acute MI during the median 8.6-year follow-up was compared among the groups divided by the levels of nHDL (<100, 100-129, and ≥130 mg/dL), LDL (<70, 70-99, and ≥100 mg/dL), triglyceride (<84, 84-149, and ≥150 mg/dL), and combination of LDL and triglyceride. Kaplan-Meier curves and multiple Cox proportional hazards models showed that higher levels of nHDL, but not LDL or triglyceride alone, were associated with higher incidence of recurrent acute MI. Furthermore, higher triglyceride levels were associated with higher incidence of recurrent MI in patients with LDL <100 mg/dL but not in those with LDL ≥100 mg/dL. Conclusions- These results indicate that management of residual risks for acute MI recurrence should include nHDL management considering both LDL and triglyceride in old MI patients under statin treatment. Clinical Trial Registration- URL: http://www.clinicaltrials.gov . Unique identifier: NCT00418041.

Coronary Artery Disease and Endothelial Dysfunction: Novel Diagnostic and Therapeutic Approaches

Coronary artery disease is the leading cause of morbidity and mortality worldwide. The most common pathophysiologic substrate is atherosclerosis which is an inflammatory procedure that starts at childhood and develops throughout life. Endothelial dysfunction is associated with the initiation and progression of atherosclerosis and is characterized by the impaired production of nitric oxide. In general, endothelial dysfunction is linked to poor cardiovascular prognosis and different methods, both invasive and non-invasive, have been developed for its evaluation. Ultrasound evaluation of flow mediated dilatation of the branchial artery is the most commonly used method to assessed endothelial function while intracoronary administration of vasoactive agents may be also be used to test directly endothelial properties of the coronary vasculature. Endothelial dysfunction has also been the subject of therapeutic interventions. This review article summarizes the knowledge about evaluation of endothelial function in acute coronary syndromes and stable coronary artery disease and demonstrates the current therapeutic approaches against endothelial dysfunction.

'Statins in retinal disease'

Statins are known for their blood cholesterol-lowering effect and are widely used in patients with cardiovascular and metabolic diseases. Research over the past three decades shows that statins have diverse effects on different pathophysiological pathways involved in angiogenesis, inflammation, apoptosis, and anti-oxidation, leading to new therapeutic options. Recently, statins have attracted considerable attention for their immunomodulatory effect. Since immune reactivity has been implicated in a number of retinal diseases, such as uveitis, age-related macular degeneration (AMD) and diabetic retinopathy, there is now a growing body of evidence supporting the beneficial effects of statins in these retinopathies. This review evaluates the relationship between statins and the pathophysiological basis of these diseases, focusing on their potential role in treatment. A PubMed database search and literature review was conducted. Among AMD patients, there is inconsistent evidence regarding protection against development of early AMD or delaying disease progression; though they have been found to reduce the risk of developing choroidal neovascular membranes (CNV). In patients with retinal vein occlusion, there was no evidence to support a therapeutic benefit or a protective role with statins. In patients with diabetic retinopathy, statins demonstrate a reduction in disease progression and improved resolution of diabetic macular oedema (DMO). Among patients with uveitis, statins have a protective effect by reducing the likelihood of uveitis development.

Statin and Its Association With Delirium in the Medical ICU

OBJECTIVES

To examine the association between statin use and the risk of delirium in hospitalized patients with an admission to the medical ICU.

DESIGN

Retrospective propensity-matched cohort analysis with accrual from September 1, 2012, to September 30, 2015.

SETTING

Hartford Hospital, Hartford, CT.

PATIENTS

An initial population of patients with an admission to a medical ICU totaling 10,216 visits were screened for delirium by means of the Confusion Assessment Method. After exclusions, a population of 6,664 was used to match statin users and nonstatin users. The propensity-matched cohort resulted in a sample of 1,475 patients receiving statin matched 1:1 with control patients not using statin.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Delirium defined as a positive Confusion Assessment Method assessment was the primary end point. The prevalence of delirium was 22.3% in the unmatched cohort and 22.8% in the propensity-matched cohort. Statin use was associated with a significant decrease in the risk of delirium (odds ratio, 0.47; 95% CI, 0.38-0.56). Considering the type of statin used, atorvastatin (0.51; 0.41-0.64), pravastatin (0.40; 0.28-0.58), and simvastatin (0.33; 0.21-0.52) were all significantly associated with a reduced frequency of delirium.

CONCLUSIONS

The use of statins was independently associated with a reduction in the risk of delirium in hospitalized patients. When considering types of statins used, this reduction was significant in patients using atorvastatin, pravastatin, and simvastatin. Randomized trials of various statin types in hospitalized patients prone to delirium should validate their use in protection from delirium.

Statins Reduce Lipopolysaccharide-Induced Cytokine and Inflammatory Mediator Release in an In Vitro Model of Microglial-Like Cells

The anti-inflammatory effects of statins (HMG-CoA reductase inhibitors) within the cardiovascular system are well-established; however, their neuroinflammatory potential is unclear. It is currently unknown whether statins' neurological effects are lipid-dependent or due to pleiotropic mechanisms. Therefore, the assumption that all statin compounds will have the same effect within the central nervous system is potentially inappropriate, with no studies to date having compared all statins in a single model. Thus, the aim of this study was to compare the effects of the six statins (atorvastatin, fluvastatin, pitavastatin, pravastatin, rosuvastatin, and simvastatin) within a single in vitro model of neuroinflammation. To achieve this, PMA-differentiated THP-1 cells were used as surrogate microglial cells, and LPS was used to induce inflammatory conditions. Here, we show that pretreatment with all statins was able to significantly reduce LPS-induced interleukin (IL)-1β and tumour necrosis factor (TNF)-α release, as well as decrease LPS-induced prostaglandin E2 (PGE2). Similarly, global reactive oxygen species (ROS) and nitric oxide (NO) production were decreased following pretreatment with all statins. Based on these findings, it is suggested that more complex cellular models should be considered to further compare individual statin compounds, including translation into in vivo models of acute and/or chronic neuroinflammation.

Nonenzymatic Mechanism of Statins in Modulating Cholesterol Particles Formation

Statin drugs are leading medication prescribed for treatment of dyslipidemic patients aimed at preventing both primary and secondary incidences of atherosclerosis-related cardiovascular events. Statin drugs competitively inhibit HMG-CoA reductase enzyme activity, thereby inhibiting cell-mediated cholesterol synthesis and reducing the low-density lipoprotein (LDL) cholesterol concentration of plasma. Conversely, the mechanism by which statins increase high-density lipoprotein (HDL) cholesterol concentration of plasma is not well understood. The plaque array method was used to examine the effect of statins on in vitro cholesterol particle formation. We observed that statins induced high-density cholesterol particle formation in buffer solution with or without the addition of human serum. Besides, simvastatin and lovastatin in their inactive pro-drug forms modulate formation of LDL and HDL cholesterol particles, indicating a novel nonenzymatic mechanism of statins. In a pilot study, screening of serum samples in the assay showed variation among patient samples in response to different statins. Specifically, screening of 50 serum samples with high cholesterol and statin treatment, compared with standard LDL-based measurement of statin efficacy, showed a good correlation for simvastatin (88%) and atorvastatin (84%). Taken together, our data indicate that statins, in addition to inhibiting enzyme-mediated cholesterol synthesis, have the capability to nonenzymatically modulate formation of LDL and HDL cholesterol particles in vitro. Similar interactions occurring in serum may provide a means to alter cholesterol particle formation in vivo.

Effect of mild endurance exercise training and pravastatin on peripheral vasodilatation of forearm resistance vessels in patients with coronary artery disease

Background Improved endothelial function may contribute to the beneficial effects of cholesterol lowering therapy in patients with coronary artery disease (CAD), but results of the effect of statin therapy on endothelial function are disparate in these patients. Exercise training has been reported to improve endothelial function of patients at risk of or with established CAD. The goal of the study was to compare the effect of mild exercise training or statin therapy on forearm endothelial function in CAD patients with average cholesterol levels.

Design and methods Twenty-eight sedentary male patients with angiographically documented CAD and average pretreatment total plasma cholesterol levels (5.1±0.9 mmol/l) aged 42–75 years were included. They were randomly assigned in a 2:1 order to either statin therapy (pravastatin, 40 mg daily) or exercise training therapy (mild endurance exercise three or more times a week). The effects of 10 weeks of either treatment on endothelium-dependent and independent vasodilation of forearm resistance vessels was assessed by plethysmography. Cardiopulmonary exercise testing was performed at baseline and after 10 weeks.

Results Ten weeks of pravastatin therapy significantly reduced low-density lipoprotein cholesterol (from 3.8±0.6 to 3.1±0.6 mmol/l at study end, P=0.04) and the ratio of total to high-density lipoprotein cholesterol (from 4.9±0.8 to 3.7±0.7 mmol/l, P=0.002). Exercise training did not significantly modify the lipid profile. Peak oxygen consumption, maximal achieved workload and exercise duration tended to improve in the exercise training group but remained unchanged in the pravastatin-treated group. Neither 10 weeks of pravastatin nor mild endurance exercise training improved endothelium-dependent or independent vasomotor function in forearm resistance vessels.

Conclusions In patients with CAD and average cholesterol levels, 10 weeks of treatment with mild endurance exercise training or with pravastatin failed to improve endothelium-dependent or independent vasomotor function in forearm resistance vessels.

The effects of quinapril and atorvastatin on the responsiveness to sildenafil in men with erectile dysfunction

Phosphodiesterase-5 (PDE-5) inhibitors are an effective therapy for the majority of men with erectile dysfunction (ED). However, many men with ED still report a suboptimal or partial response even after an adequate trial of oral PDE-5 therapy. Since ED is associated with impaired vascular function and both atorvastatin and quinapril have been previously shown to improve vascular function, we examined the effects of adjunctive treatment with these medications in men with vasculogenic ED who were suboptimal responders to 100 mg of sildenafil. Men with ED and suboptimal response to sildenafil were randomly assigned to 3 months of treatment with atorvastatin 40 mg ( n = 12), quinapril 10 mg ( n = 10), or placebo ( n = 13), along with continued adjunctive sildenafil use. Measured variables included: International Index of Erectile Function (IIEF) questionnaire, brachial artery flow-mediated dilation (FMD), endothelium-independent dilation (EID) via nitroglycerin, penile Doppler blood flow, blood pressure (BP), lipids, and C-reactive protein (CRP). Compared to placebo, quinapril ( p < 0.01) significantly improved symptoms of ED as measured by the IIEF-5 questionnaire. There was a trend toward a significant improvement in IIEF-5 with atorvastatin. Similarly, quinapril significantly improved the IIEF ED Domain ( p < 0.05). Other peripheral and penile vascular parameters were unchanged with drug therapy as compared to placebo. In conclusion, treatment with quinapril, in combination with sildenafil, improved ED in men with suboptimal response to sildenafil alone. Atorvastatin demonstrated a trend toward improved ED in this group.

Cellular and molecular mechanisms of statins: an update on pleiotropic effects

Coronary artery disease (CAD) is the leading cause of death worldwide. The efficacy and safety of statins (3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors) in primary and secondary prevention of CAD are confirmed in several large studies. It is well known that statins have some pleiotropic, anti-atherosclerotic effects. We review the molecular mechanisms underlying the beneficial effects of statins revealed in recently published studies. Endothelial cell injury is regarded as the classic stimulus for the development of atherosclerotic lesions. In addition, the inflammatory process plays an important role in the aetiology of atherosclerosis. In particular, chronic inflammation plays a key role in coronary artery plaque instability and subsequent occlusive thrombosis. Our previous reports and others have demonstrated beneficial effects of statins on endothelial dysfunction and chronic inflammation in CAD. A better understanding of the molecular mechanism underlying the effectiveness of statins against atherosclerosis may provide a novel therapeutic agent for the treatment of coronary atherosclerosis. The present review summarizes the cellular and molecular mechanism of statins against coronary atherosclerosis.

Puberty as an accelerator for diabetes complications

Much is written about how difficult it is to deal with diabetes during adolescence, and rightly so. Less is understood as to how puberty may be an accelerator of vascular complications. With the increase in childhood diabetes, complication risks need to be revisited in relation to puberty and the secular increase in adiposity. Recent data suggest greater risk for severe vascular complications in those with diabetes during puberty, compared with young people who develop diabetes after puberty. It is also widely recognized that higher hemoglobin A1c (HbA1c) results are often seen during the pubertal period. This article will review complication outcomes in relation to puberty and examine mechanisms by which puberty may modify risk above glycemic exposure, and possible gender disparities in the risk of complications in the adolescent period.

Sodium nitrite in patients with peripheral artery disease and diabetes mellitus: safety, walking distance and endothelial function

Nitrite stores decrease after exercise in patients with peripheral artery disease (PAD) and diabetes represents decreased nitric oxide (NO) bioavailability that may contribute to endothelial dysfunction and limit exercise duration. The primary objective of this placebo-controlled study was the safety and tolerability of multiple doses of oral sodium nitrite in patients with PAD, predominantly with diabetes, over a period of 10 weeks. The primary efficacy endpoint was endothelial flow-mediated dilatation (FMD) and secondary efficacy endpoints included a 6-minute walk test and quality of life assessment. Of the 55 subjects, the most common side effects attributed to sodium nitrite were a composite of headache and dizziness occurring in 21% with the 40 mg dose and 44% with the 80 mg dose. There was no clinically significant elevation of methemoglobin. FMD non-significantly worsened in the placebo and 40 mg groups, but was stable in the 80 mg group. Diabetic patients receiving 80 mg had significantly higher FMD compared with the placebo and 40 mg groups. There was no significant change in 6-minute walk test or quality of life parameters over time compared to placebo. In conclusion, sodium nitrite therapy is well tolerated in patients with PAD. The possible clinical benefit of sodium nitrite should be studied in a larger and fully powered trial.

Statins as anti-inflammatory agents in atherogenesis: molecular mechanisms and lessons from the recent clinical trials

Ample evidence exists in support of the potent anti-inflammatory properties of statins. In cell studies and animal models statins exert beneficial cardiovascular effects. By inhibiting intracellular isoprenoids formation, statins suppress vascular and myocardial inflammation, favorably modulate vascular and myocardial redox state and improve nitric oxide bioavailability. Randomized clinical trials have demonstrated that further to their lipid lowering effects, statins are useful in the primary and secondary prevention of coronary heart disease (CHD) due to their anti-inflammatory potential. The landmark JUPITER trial suggested that in subjects without CHD, suppression of low-grade inflammation by statins improves clinical outcome. However, recent trials have failed to document any clinical benefit with statins in high risk groups, such in heart failure or chronic kidney disease patients. In this review, we aim to summarize the existing evidence on statins as an anti-inflammatory agent in atherogenesis. We describe the molecular mechanisms responsible for the anti-inflammatory effects of statins, as well as clinical data on the non lipid-lowering, anti-inflammatory effects of statins on cardiovascular outcomes. Lastly, the controversy of the recent large randomized clinical trials and the issue of statin withdrawal are also discussed.

Central versus peripheral cardiovascular risk in metabolic syndrome

Individuals with metabolic syndrome (MetS; i.e., three of five of the following risk factors (RFs): elevated blood pressure, waist circumference, triglycerides, blood glucose, or reduced HDL) are thought to be prone to serious cardiovascular disease and there is debate as to whether the disease begins in the peripheral vasculature or centrally. This study investigates hemodynamics, cardiac function/morphology, and mechanical properties of the central (heart, carotid artery) or peripheral [total peripheral resistance (TPR), forearm vascular bed] vasculature in individuals without (1–2 RFs: n = 28), or with (≥3 RFs: n = 46) MetS. After adjustments for statin and blood pressure medication use, those with MetS had lower mitral valve E/A ratios (<3 RFs: 1.24 ± 0.07; ≥3 RFs: 1.01 ± 0.04; P = 0.025), and higher TPR index (<3 RFs: 48 ± 2 mmHg/L/min/m²; ≥3 RFs: 53 ± 2 mmHg/L/min/m²; P = 0.04). There were no differences in heart size, carotid artery measurements, cardiovagal baroreflex, pulse-wave velocity, stroke volume index, or cardiac output index due to MetS after adjustments for statin and blood pressure medication use. The use of statins was associated with increased inertia in the brachial vascular bed, increased HbA1c and decreased LDL cholesterol. The independent use of anti-hypertensive medication was associated with decreased predicted VO2max, triglycerides, diastolic blood pressure, interventricular septum thickness, calculated left ventricle mass, left ventricle posterior wall thickness, and left ventricle pre-ejection period, but increased carotid stiffness, HDL cholesterol, and heart rate. These data imply that both a central cardiac effect and a peripheral effect of vascular resistance are expressed in MetS. These data also indicate that variance in between-group responses due to pharmacological treatments are important factors to consider in studying cardiovascular changes in these individuals.

Flow-Mediated Vasodilatation and Intima-Media Thickness in Patients with Coexisting Heart Failure and Diabetes Receiving Medical Therapy

Objective

Intensive medical treatment of heart failure (HF) patients with diabetes may reduce the endothelial dysfunction and the accelerated atherosclerotic process seen in these patients. To study this, we investigated the endothelial function and the presence of atherosclerosis as measured by flow-mediated vasodilatation (FMD) and intima-media thickness (IMT) in intensively treated patients with coexisting HF and diabetes.

Research Design and Method

FMD of the brachial artery and IMT of the common carotid arteries were determined in 26 patients with systolic HF and diabetes who were in intensive medical therapy, as well as in 19 healthy controls. The two groups were matched according to age and sex. In all subjects left ventricular ejection fraction was measured by two-dimensional echocardiography. Biochemical parameters including serum cholesterol, HDL and LDL, triglyceride, glucose, hemoglobin/hemoglobin-A1C (HbA1C), brain natriuretic peptide (BNP) and N-terminal pro-BNP were also assessed.

Results

Mean FMD and IMT did not differ significantly between patients and controls. Left ventricular ejection fraction was lower in patients compared to controls (P < 0.001). The patients had a higher mean BNP, NT pro-BNP, triglyceride, HbA1C and glucose in comparison to controls. Cholesterol, HDL-cholesterol and LDL-cholesterol were lower in patients compared to controls.

Conclusions

Intensively treated patients with coexisting systolic HF and diabetes seem to have normal endothelial function as measured by FMD and they have no sign of accelerated atherosclerosis as measured by IMT. This suggests a positive effect of medication on the cardiovascular alterations in this group of patients.

Pharmacological actions of statins: a critical appraisal in the management of cancer

Statins, among the most commonly prescribed drugs worldwide, are cholesterol-lowering agents used to manage and prevent cardiovascular and coronary heart diseases. Recently, a multifaceted action in different physiological and pathological conditions has been also proposed for statins, beyond anti-inflammation and neuroprotection. Statins have been shown to act through cholesterol-dependent and -independent mechanisms and are able to affect several tissue functions and modulate specific signal transduction pathways that could account for statin pleiotropic effects. Typically, statins are prescribed in middle-aged or elderly patients in a therapeutic regimen covering a long life span during which metabolic processes, aging, and concomitant novel diseases, including cancer, could occur. In this context, safety, toxicity, interaction with other drugs, and the state of health have to be taken into account in subjects treated with statins. Some evidence has shown a dichotomous effect of statins with either cancer-inhibiting or -promoting effects. To date, clinical trials failed to demonstrate a reduced cancer occurrence in statin users and no sufficient data are available to define the long-term effects of statin use over a period of 10 years. Moreover, results from clinical trials performed to evaluate the therapeutic efficacy of statins in cancer did not suggest statin use as chemotherapeutic or adjuvant agents. Here, we reviewed the pharmacology of the statins, providing a comprehensive update of the current knowledge of their effects on tissues, biological processes, and pathological conditions, and we dissected the disappointing evidence on the possible future use of statin-based drugs in cancer therapy.

Effect of acute changes in oxygen tension on flow-mediated dilation. Relation to cardiovascular risk

OBJECTIVE

Oxygen-dependent changes in vascular diameters may be detrimental when the endothelium is dysfunctional.

DESIGN

Endothelial responsiveness was evaluated by brachial ultrasound and flow-mediated/nitroglycerin-mediated dilation (FMD/NMD). FMD/NMD was investigated in males with increased risk of cardiovascular disease (mean age 44+/-2 years, n=10) and matched controls without risk factors (44+/-2 years, n=10). FMD/NMD was assessed during normoxia (21% O2, 79% N2), while inhaling hypoxic gas (12.5% O2, FMDHyp/NMD), and 100% O2 supplementation (FMDO2/NMD). In a second study we addressed the effect of lipid lowering. Twenty persons with cardiovascular risk (mean age 50+/-2 years) were treated with atorvastatin (80 mg/day) and FMD/NMD was measured during normoxia, hypoxia and oxygen supplementation before, after 1 day and 3 months.

RESULTS

Oxygen supplementation evoked vasoconstriction, while FMDHyp/NMD was reduced compared to FMD/NMD. Atorvastatin significantly lowered total cholesterol, LDL cholesterol, and ADMA after 1 day of treatment, while triglycerides, ApoB and hsCRP were lowered after 3 months. Atorvastatin did not change FMD/NMD irrespective of oxygen tension.

CONCLUSION

Irrespective of risk factors or atorvastatin, hypoxia reduced endothelial vasodilation while oxygen supplementation evoked vasoconstriction.

Training-induced increase in nitric oxide metabolites in chronic heart failure and coronary artery disease: an extra benefit of water-based exercises?

BACKGROUND

Rehabilitation programs involving immersed exercises are more and more frequently used, with severe cardiac patients as well.

DESIGN

This study investigated whether a rehabilitation program including water-based exercises has additional effects on the cardiovascular system compared with a traditional land-based training in heart disease patients.

METHODS

Twenty-four male stable chronic heart failure patients and 24 male coronary artery disease patients with preserved left ventricular function participated in the study. Patients took part in the rehabilitation program performing cycle endurance exercises on land. They also performed gymnastic exercises either on land (first half of the participants) or in water (second half). Resting plasma concentration of nitric oxide metabolites (nitrate and nitrite) and catecholamine were evaluated, and a symptom-limited exercise test on a cycle ergometer was performed before and after the rehabilitation program.

RESULTS

In the groups performing water-based exercises, the plasma concentration of nitrates was significantly increased (P = 0.035 for chronic heart failure and P = 0.042 for coronary artery disease), whereas it did not significantly change in the groups performing gymnastic exercise on land. No changes in plasma catecholamine concentration occurred.

CONCLUSION

In every group, the cardiorespiratory capacity of patients was significantly increased after rehabilitation. The water-based exercises seemed to effectively increase the basal level of plasma nitrates. Such changes may be related to an enhancement of endothelial function and may be of importance for the health of the patients.

Effects of statins on endothelial function in patients with coronary artery disease

BACKGROUND

Flow-mediated dilatation (FMD) of the brachial artery is a method capable of detecting endothelium dysfunction. Statins are generally consent drugs for reducing cardiovascular morbidity and mortality and are shown to improve the systemic endothelial function.

HYPOTHESIS

The aim of our study was to assess the endothelial function using FMD of the brachial artery in patients with different degrees of coronary artery stenosis with respect to their treatment with statins.

METHODS

We evaluated the FMD of 221 patients with coronary arteriography performed, of whom 99 (44.8%) were receiving statins and 122 (55.2%) were not receiving statins.

RESULTS

We did not find a statistically significant difference in the FMD values between the patients with and without a statin treatment: 5.57 +/- 5.68 and 4.69 +/- 4.48, respectively, P = .581. In the subgroup of patients without angiographically visible coronary artery stenoses or with stenoses <20% (86 patients), patients undergoing statin treatment had a significantly better endothelial function compared to patients without such a treatment: FMD 9.24 +/- 6.87 and 6.50 +/- 4.51, respectively, P = .047.

CONCLUSIONS

FMD could not distinguish between the patients who were treated with statin and those not treated with statins with the same demographic, clinical, and angiographic characteristics. The only exception was in the group of patients with a minor coronary disease. Statin treatment had a more pronounced effect in the earlier stages of coronary atherosclerosis.

The association of acute exercise-induced ischaemia with systemic vasodilator function in patients with peripheral arterial disease

Abstract

Patients with peripheral arterial disease (PAD) frequently experience ischaemic attacks of the affected tissues during exercise. The present study assesses the association of transient exercise-induced leg ischaemia with vasodilator function of the clinically unaffected brachial artery over the course of 4 hours. Thirty male patients with symptomatic PAD and 14 age- and sex-matched healthy controls were included in the study. They performed a treadmill exercise until intolerable exercise-induced ischaemic pain occurred in the affected lower extremity, or for at most 10 min. Flow-mediated dilation (FMD) of the brachial artery was measured at baseline, 30 minutes, 2 hours and 4 hours after exercise. Baseline FMD values were significantly diminished in patients (7.03 ± 1.99% vs 8.22 ± 1.60% in controls, p = 0.009). A significant decrease in FMD was observed in patients after exercise (at 30 minutes: 3.92 ± 1.78% vs 7.03 ± 1.99% at baseline, p < 0.001; at 2 hours: 6.36 ± 2.12% vs 7.03 ± 1.99% at baseline, p = 0.005), followed by a gradual return to its baseline value, whereas FMD in controls non-significantly increased after exercise. The difference in the pattern of FMD change over time between patients and controls was significant ( p < 0.001). This study shows that in PAD patients ischaemia during intermittent claudication is related to a transitory functional deterioration of the distant arteries. This indicates the harmful systemic effects of repeated ischaemic attacks during exercise and might explain the generalized and advanced nature of atherosclerotic disease in PAD patients.

New and emerging risk factors for CVD

Morphological and immunocytochemical studies have elucidated the complex processes involved in atherogenesis. The notion of plaque instability has emerged from this work and underscored the importance of inflammation in determining clinical complications associated with atherosclerosis, such as acute coronary syndrome. Cells of the immune system have been detected within atherosclerotic lesions and auto-antibodies directed against modified LDL and heat-shock proteins have been identified in the blood of individuals with atherosclerosis. The use of risk 'engines', e.g. the Framingham coronary risk score, has facilitated the identification of individuals at high risk, but the constituent classical risk factors used in these algorithms do not adequately differentiate individuals at moderate risk. As age is a major component of the equations used in these algorithms they are not particularly useful in young adults, and their applicability to non-Caucasian populations has been questioned. Biomarkers of early disease and plaque instability have therefore both been sought. Although some of these markers have been shown individually to be associated with a significant hazard ratio, no substantial improvement in discrimination has been demonstrated when they are incorporated into a risk 'engine'. The latter has generally been assessed by receiver operator characteristic curve analysis, although this approach has been criticised. Other modalities, including imaging and functional assessments of vascular function, are now being developed for clinical use.

Reduction in blood pressure with statins: results from the UCSD Statin Study, a randomized trial

BACKGROUND

Some studies have suggested reductions in blood pressure (BP)with statin treatment, particularly in persons with hypertension. Randomized trial evidence is limited.

METHODS

We performed a randomized, double-blind, placebo-controlled trial with equal allocation to simvastatin, 20 mg; pravastatin sodium,40 mg; or placebo for 6 months. Nine hundred seventy-three men and women without known cardiovascular disease or diabetes mellitus, with low-density lipoprotein cholesterol screening levels of 115 to 190 mg/dL, had assessment of systolic and diastolic BP (SBP and DBP, respectively). Blood pressure values were compared for placebo vs statins by intention-to-treat (ITT) analysis. Additional analyses were performed that (1) were confined to subjects with neither high baseline BP (SBP>140 mm Hg or DBP>90 mm Hg) nor receiving BP medications, to exclude groups in whom BP medications or medication changes may have influenced results, and (2) separately evaluated simvastatin and pravastatin (vs placebo). The time course of BP changes after statin initiation and the effect of stopping statins on BP were examined.

RESULTS

Statins modestly but significantly reduced BP relative to placebo,by 2.2 mm Hg for SBP (P=.02) and 2.4 mm Hg for DBP (P<.001) in ITT analysis. Blood pressure reductions ranged from 2.4 to 2.8 mm Hg for both SBP and DBP with both simvastatin and pravastatin, in those subjects with full follow-up, and without potential for influence by BP medications (ie, neither receiving nor meriting BP medications).

CONCLUSIONS

Reductions in SBP and DBP occurred with hydrophilic and lipophilic statins and extended to normotensive subjects. These modest effects may contribute to the reduced risk of stroke and cardiovascular events reported on statins. Trial Registration clinicaltrials.gov Identifier: NCT00330980.

Potential roles for statins in critically ill patients

The 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) are the most commonly prescribed agents for hypercholesterolemia and have revolutionized the management of hyperlipidemia and the area of cardiovascular risk reduction. However, recent data suggest that their effects go well beyond the lipid lowering seen with long-term use and may include acute antiinflammatory activity, anticoagulation, immunomodulation, as well as promotion of changes in smooth-muscle tone. Because of these data, promising research has begun into the use of these agents in various critical care areas such as the early phases of sepsis, bacteremia, and ischemic stroke. Recent data also show a decrease in cerebral vasospasm after subarachnoid hemorrhage, an area deficient in therapeutic options. More research is necessary to ascertain the true role of statins in the treatment of these various disorders. Nevertheless, the concept of a statin's role as being only a routine preventive therapy with benefits limited to patients undergoing extended treatment is rapidly becoming inaccurate.

Endothelial function, arterial stiffness and lipid lowering drugs

The endothelium is a dynamic organ that plays a pivotal role in cardiovascular homeostasis. Alteration in endothelial function precedes the development of atherosclerosis and contributes to its initiation, perpetuation and clinical manifestations. It has been suggested that the assessment of endothelial function could represent a barometer of vascular health that could be used to gauge cardiovascular risk. This review summarises the various methods used to assess endothelium-dependent vasodilatation and their potential prognostic implications. In addition, the techniques used to evaluate arterial stiffness are discussed. The latter is to some extent controlled by the endothelium and has been the subject of considerable research in recent years. This paper also discusses the effects of lipid lowering treatment on both endothelial function and arterial stiffness.

Statin Therapy for Vascular Failure

There is increasing evidence that statins reduce cardiovascular events such as coronary artery disease or stroke in hypercholesterolemic patients in both primary and secondary prevention. The striking benefit achieved with statin treatments in patients with a wide range of cholesterol levels cannot be attributed to their cholesterol lowering effect alone. Substantial data has recently accumulated showing that statins exert various effects on multiple targets, namely pleiotropic effects, especially targeting the concept of 'vascular failure', including the improvement of vascular endothelial function, inhibition of vascular smooth muscle cell proliferation and migration, anti-inflammatory actions, anti-oxidative effects or stabilization of vulnerable plaques. These effects have potential in the treatments of coronary artery disease in various settings, such as prevention of its onset as well as its progression, or plaque rupture. Statin therapy should be more extensively applied even in normolipidemic patients if there are additional risk factors such as hypertension, diabetes mellitus, or others. Furthermore, statins may be used to intervene in earlier stage risk conditions such as postprandial hyperlipidemia or hyperglycemia, insulin resistant state, masked hypertension, or metabolic syndrome to further reduce mortality or morbidity of coronary artery disease and heart failure.

Atorvastatin therapy improves exercise oxygen uptake kinetics in post-myocardial infarction patients

BACKGROUND

Statins represent a modern mainstay of the drug treatment of coronary artery disease and acute coronary syndromes. Reduced aerobic work performance and slowed VO(2) kinetics are established features of the clinical picture of post-myocardial infarction (MI) patients. We tested the hypothesis that statin therapy improves VO(2) exercise performance in normocholesterolaemic post-MI patients.

MATERIALS AND METHODS

According to a double-blinded, randomized, crossover and placebo-controlled study design, in 18 patients with uncomplicated recent (3 days) MI we investigated the effects of atorvastatin (20 mg day(-1)) on gas exchange kinetics by calculating VO(2) effective time constant (tau) during a 50-watt constant workload exercise, brachial artery flow-mediated dilatation (FMD) as an index of endothelial function, left ventricular function (echocardiography) and C-reactive protein (CRP, as an index of inflammation). Atorvastatin or placebo was given for 3 months each.

RESULTS

Atorvastatin therapy significantly improved exercise VO(2) tau and FMD, and reduced CRP levels. We did not observe changes in cardiac contractile function and relaxation properties during all study periods in either group.

CONCLUSIONS

In post-MI patients exercise performance is a potential additional target of benefits related to statin therapy. Endothelial function improvement is very likely implicated in this newly described therapeutic property.

Early effects on endothelial function of atorvastatin 40 mg twice daily and its withdrawal

Combined hyperlipidemia is associated with endothelial dysfunction. Atorvastatin has lipid-lowering and pleiotropic properties, including a protective effect on endothelial function. This study investigated the short- and medium-term effects of therapy with atorvastatin and of its discontinuation on lipid lowering and endothelial function. In 33 patients with combined hyperlipidemia who had been randomized and treated for 6 weeks with 40 mg of atorvastatin twice daily (n = 23) or placebo (n = 10), fasting lipid levels and flow-mediated dilation (FMD) of the brachial artery were measured at baseline, after 12 hours, 1 week, and 6 weeks during therapy, and 36 hours after discontinuation of therapy. Thereafter, all patients received 20 mg/day of atorvastatin for another 6 weeks. In the atorvastatin group, low-density lipoprotein cholesterol was decreased by 30% and 46% after 1 and 6 weeks, respectively (p <0.0001 for the 2 comparisons). In patients who already showed an impaired FMD at the beginning of the study (n = 15), atorvastatin caused a significant improvement in FMD, from 2.6% at baseline to 4.0% and 6.3% after 1 and 6 weeks, respectively (p <0.05 and <0.001). Thirty-six hours after withdrawal of atorvastatin, the FMD in this group decreased again to 2.8% (p <0.05), whereas low-density lipoprotein cholesterol level remained unchanged. The 6 patients with normal FMD at baseline showed no improvement in FMD during therapy or any decrease after withdrawal of the drug. In conclusion, only patients with endothelial dysfunction profit from high-dose atorvastatin treatment. When the treatment is abruptly discontinued, the effect on FMD disappears in 36 hours.

Anti-Inflammatory Effects of Statins: Clinical Evidence and Basic Mechanisms

Chronic inflammation is a key feature of vascular disease states such as atherosclerosis. Multiple clinical studies have shown that a class of medications termed statins lower cardiovascular morbidity and mortality. Originally developed to lower serum cholesterol, increasing evidence suggests that these medications have potent anti-inflammatory effects that contribute to their beneficial effects in patients. Here, we discuss the clinical and experimental evidence underlying the anti-inflammatory effects of these agents.

Effect of age on lipid profiles in pediatric heart transplant recipients

This study's objectives were to determine if pediatric orthotopic heart transplant (OHT) recipients over all ages develop hyperlipidemia and, secondarily, to identify the effects of immunosuppressive agents and statins on lipid profiles in these patients. Retrospective chart review was performed for pediatric patients transplanted between January 1987 and June 2002. Of the 100 OHTs performed, 50 patients satisfied the inclusion criteria and were grouped by age at OHT as follows: group 1 (n = 16): 0-4 yr; group 2 (n = 10): 5-9 yr; group 3 (n = 15): 10-14 yr; group 4 (n = 9): 15-18 yr. There were 2789 lipid levels recorded, and each patient had an average of 14 post-OHT lipoprotein panels measured. Post-OHT total cholesterol and low-density lipoprotein (LDL) levels were significantly greater than those of the general population for the entire follow-up period in all age groups, except for LDL levels in group 2. Cyclosporin level and prednisone dose were positively associated with total cholesterol and LDL levels (p < 0.03). Statins significantly decreased total cholesterol and LDL levels (p < 0.001). Hyperlipidemia affects OHT patients of all ages. Even the youngest patients may benefit from immunosuppression using an alternative to cyclosporin, such as tacrolimus, and steroid-free regimens, which may improve lipid profiles. Once safety and efficacy data are available, all age groups may benefit from statins.

Clinical impact of vasomotor function assessment and the role of ACE-inhibitors and statins

Impaired endothelial function is recognised as one of the earliest events of atherogenesis. Endothelium-dependent vasomotion has been the principal method to assess endothelial function. In this article, we will discuss the clinical value of the different techniques to evaluate endothelium-dependent vasomotion. To date, there seems not to be a simple and reliably endothelial function test to identify asymptomatic subjects at increased risk for cardiovascular disease in clinical practice. Recent studies indicate that pharmacological interventions, in particular with ACE-inhibitors and statins, might improve endothelial function. However, there is no solid evidence that improvement of endothelial function is a necessity for the observed reduction in cardiovascular events by these compounds. Overall, at this moment, there is no place in clinical practice for the use of endothelial function as a method for risk assessment or target of pharmacological interventions.

The prevention of diabetic microvascular complications of diabetes: is there a role for lipid lowering?

The role of hyperglycemia in the development of microvascular complications of diabetes, such as nephropathy, retinopathy and neuropathy, has been well documented. Evidence is accumulating to support the concept that dyslipidemia can also contribute to the development of these complications. Lipid-lowering agents, such as statins, have been shown to prevent cardiovascular events in patients with diabetes. However, in addition to preventing macrovascular diseases, statins may also be able to retard the progression of microvascular complications of diabetes. Indeed, in addition to reducing lipid levels, these agents can improve endothelial function and reduce oxidative stress, which can improve microvascular function. These findings would provide further support for the use of lipid-lowering agents in patients with diabetes.

Evaluating Cardiovascular Pathophysiology and Anatomy in Atherosclerosis

The process of atherosclerosis begins with endothelial dysfunction from impaired bioavailability of NO and progresses through multiple stages of plaque development. Impaired endothelial function decreases NO and increases oxidized macromolecules such as low-density lipoprotein cholesterol. Oxidized low-density lipoprotein cholesterol accumulates in subendothelial space, forming plaques that may eventually compromise the lumen. Acute coronary events result from plaque rupture and consequent thrombus formation and abrupt occlusion of the vessel lumen. New diagnostic methods such as flow-mediated dilation of the brachial artery can detect endothelial dysfunction, and intravascular ultrasound can detect early plaque formation in the arterial wall. These techniques may provide a means to identify patients at risk for adverse cardiovascular outcomes, thereby enabling physicians to potentially prevent adverse events by early initiation of lipid-lowering therapy.

Statins and the response to myocardial injury

The benefits of long-term statin (HMG-CoA reductase inhibitor) treatment for preventing coronary events have been well documented in several large-scale prospective clinical trials. By influencing the determinants of myocardial injury, statins may produce direct cardioprotective effects in the ischemic myocardium and prevent further damaging recurrent events. Although not proven fully in a clinical setting, cholesterol-independent or 'pleiotropic' effects of statins are thought to protect against myocardial injury and may occur via a number of mechanisms. Endothelial dysfunction occurs early in the development of atherosclerosis and is associated with a reduction in endothelial nitric oxide (NO) production. Statins have been shown to increase the expression of endothelial NO synthase, with subsequent augmentation of NO in the vasculature. Statins have also been reported to have anti-inflammatory effects, reducing the release of cytokines and chemokines, decreasing the expression of pro-inflammatory cell adhesion molecules, and reducing the accumulation of neutrophils in myocardial tissue following ischemia and reperfusion. Indeed, the role of statins in reducing infarct size is supported by data from a number of preclinical studies. Statin treatment, administered at the onset of reperfusion, has been shown to reduce infarct size by approximately 50% following ischemia in various animal models, and this may be an NO-dependent effect. Randomized clinical trials have indicated that early initiation of statin treatment is associated with a reduction in both the rate of recurrence of cardiovascular events and death in patients with acute coronary syndrome. In addition, decreased rates of myocardial infarction and mortality were demonstrated in several retrospective studies where statin treatment was administered before an interventional procedure. There is a need for further clinical trials to fully elucidate the importance of pre-procedural statin therapy and to determine the extent and mechanisms by which statins exert their cardioprotective effects.

Fetal and childhood onset of adult cardiovascular diseases

Childhood onset of adult cardiovascular disease has become a significant public health problem. Whether genetic, environmental, or fetal influences are the primary culprits in the epidemic of the cardiovascular disease seen today remains unknown. The benefits of an overall physically active lifestyle that includes weight control, lower blood pressure, avoidance of tobacco use, and consistent exercise are clear and can impact the overall health of children and adolescents. Physicians who care for children and adolescents must begin to incorporate screening of adult cardiovascular disorders into their practice. Better understanding of the etiology of these disease states will bring with it enhanced preventive and targeted therapies.

Determinants of arterial nitrate-mediated dilatation in children: role of oxidized low-density lipoprotein, endothelial function, and carotid intima-media thickness

BACKGROUND

Impaired arterial dilatation response to nitroglycerin has been observed in adults with risk factors for atherosclerosis and in patients with established atherosclerotic disease. This defect parallels changes in vascular endothelial function and may be attributed to increased oxidative stress. Because atherosclerosis begins in childhood, we examined the correlates of nitrate-mediated dilatation (NMD) in children, including brachial artery endothelial function, oxidized LDL, and carotid artery intima-media thickness (IMT).

METHODS AND RESULTS

Brachial artery flow-mediated endothelium-dependent dilatation (FMD) and nitrate-mediated smooth muscle function, IMT of the carotid bulb, and brachial artery and oxidized LDL were measured in 142 children (mean age, 11 years; range, 8 to 17 years), including 87 healthy children, 41 diabetic children, and 14 children with familial hypercholesterolemia. NMD correlated directly with FMD (r=0.46, P<0.001) and inversely with brachial artery baseline diameter (r=-0.36, P<0.001), age (r=-0.25, P=0.003), body mass index (r=-0.31, P<0.001), diabetes (r=-0.22, P=0.008), oxidized LDL (r=-0.18, P=0.045), and IMT (r=-0.33, P<0.001). In a multivariate regression model, the significant correlates for NMD were FMD response (beta=0.003, P<0.001), brachial artery diameter (beta=-0.03, P=0.01), oxidized LDL (beta=-0.07, P=0.02), and IMT (beta=-0.15, P=0.03).

CONCLUSIONS

Reduced endothelial function, increased oxidative stress, and preclinical carotid atherosclerosis are independent determinants of impaired NMD in children. These data thus suggest that primary nitrate tolerance occurs in children at risk for atherosclerosis.