A randomized trial of aggressive lipid reduction for improvement of myocardial ischemia, symptom status, and vascular function in patients with coronary artery disease not amenable to intervention

The comparative impact among different intensive statins and combination therapies with niacin/ezetimibe on carotid intima-media thickness: a systematic review, traditional meta-analysis, and network meta-analysis of randomized controlled trials

PURPOSE

To compare the impact of different statins therapies on the reduction of carotid intima-media thickness (CIMT) may reflect their cardiovascular benefits which is useful in clinical decision.

METHODS

PubMed, EMBASE, Cochrane Library, and Web of Science were searched, and 3539 articles published from 1992 to 2020 were retrieved. CIMT in randomized controlled trials for statins therapies were included for traditional and network meta-analyses analyzed by Stata 16. The quality of included studies was assessed by the Cochrane Collaboration's tool.

RESULTS

Thirty-three randomized controlled trials (n=8762) were eligible for network meta-analysis, of which 18 randomized controlled trials (n=5252) were included for comparison between statins and no statins and 11 randomized controlled trials (n=1338) were included for comparison between high-intensity statins or combination with niacin/ezetimibe and moderate/low-intensity statins in 2 traditional meta-analyses. In the traditional meta-analyses, the statins groups significantly reduce CIMT compared to no statins (standard mean difference=-0.207, 95% confidence interval: -0.291 to -0.123, p<0.001), while high-intensity statins or combination with niacin/ezetimibe performed significant CIMT reduction compared to moderate/low-intensity statins (standard mean difference=-0.287, 95% confidence interval: -0.460 to -0.114, p=0.001). In the network meta-analysis, a relative rank for the ability to reduce CIMT was given as follows: combination therapy with niacin (mean rank: 1.7), high-intensity statins, combination therapy with ezetimibe, and moderate/low-intensity statins.

CONCLUSION

Statins combined with niacin performed a greater CIMT reduction compared to high-intensity statins alone and combination therapies with ezetimibe. The advantage of niacin-combined statins therapies to improve cardiovascular endpoint needs further validation through randomized controlled trials.

CLINICAL TRIAL REGISTRATION

PROSPERO, CRD42020175972.

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.

Rationale and design of a phase II clinical trial of aspirin and simvastatin for the treatment of pulmonary arterial hypertension: ASA-STAT

BACKGROUND

Pulmonary arterial hypertension (PAH) is a progressive disease which causes exercise limitation, heart failure, and death. Aspirin and simvastatin are highly effective and safe therapies for other cardiovascular diseases characterized by platelet activation and endothelial dysfunction, but have not been formally studied in PAH.

METHODS

ASA-STAT is a phase II, randomized, double-blind, placebo-controlled 2 × 2 factorial clinical trial of aspirin and simvastatin in patients with PAH. A total of 92 subjects were to be randomized to aspirin or aspirin placebo and simvastatin or simvastatin placebo. The primary outcome is the distance walked in 6 min at 6 months after randomization. Secondary measures include brachial artery flow-mediated dilation, circulating biomarkers of platelet and endothelial function, functional class, quality-of-life, and time to clinical end points. The incidence of adverse events will be compared between treatment groups. SCREENING AND ENROLLMENT: We screened a total of 712 individuals with PAH. Sixty-five subjects were enrolled when the trial was terminated for futility in reaching the primary end point for simvastatin.

CONCLUSIONS

This study aims to determine whether aspirin or simvastatin have beneficial biologic or clinical effects in patients with PAH. The safety and side effects of these commonly prescribed cardiovascular drugs will also be assessed.

Full-dose atorvastatin versus conventional medical therapy after non-ST-elevation acute myocardial infarction in patients with advanced non-revascularisable coronary artery disease

AIMS

This study tested the hypothesis that the addition of full-dose atorvastatin (80 mg/day) to conventional medical treatment could reduce ischaemic recurrences after non-ST-elevation acute myocardial infarction (NSTE-AMI) in patients with severe and diffuse coronary artery disease (CAD) not amenable to any form of mechanical revascularisation.

METHODS AND RESULTS

The study was an open-label, randomised, controlled, blinded end-point classification trial, employing the PROBE (Prospective Open Treatment and Blinded End Point Evaluation) design. A total of 290 patients (mean age 74.6 +/- 9.6 years) with NSTE-AMI and angiographic evidence of severe and diffuse CAD, not amenable to revascularisation by either coronary surgery or angioplasty, were randomised to atorvastatin 80 mg/day (n = 144) or conventional medical treatment (n = 146). A primary end point event (combination of cardiovascular death, non-fatal acute myocardial reinfarction and disabling stroke within 12 months of randomisation) occurred in 16.0% of patients treated with atorvastatin 80 mg/day and in 26.7% of patients receiving conventional treatment (HR 0.56; 95% CI 0.33-0.93, p = 0.027). The study was not blinded. Consequently, a bias in the assessment of clinical outcome cannot be completely excluded.

CONCLUSIONS

In conclusion, when compared with a conventional treatment strategy, full-dose therapy with atorvastatin 80 mg/day provides greater protection against ischaemic recurrences after NSTE-AMI in patients with severe, diffuse, non-revascularisable CAD.

Effect of atorvastatin on peripheral endothelial function and systemic inflammatory markers in patients with stable coronary artery disease

BACKGROUND

Endothelial dysfunction, detectable by an impaired flow-mediated vasodilation (FMD) of the brachial artery, has been shown to be associated with increased levels of circulating proinflammatory markers. Therapeutic interventions such as lipid-lowering with statins increase FMD and decrease inflammatory markers, like soluble (s) E-selectin, soluble intercellular adhesion molecule-1 (sICAM-1) or high-sensitivity Creactive protein (hsCRP). The effect of atorvastatin therapy on both FMD and inflammatory markers in patients with stable coronary artery disease (CAD) has not been investigated.

METHODS

Thirty hypercholesterolemic patients with angiographically documented stable coronary artery disease (CAD) were randomized to placebo or atorvastatin (20 mg/d) for 3 months. FMD was assessed using highresolution ultrasound (13 MHz, Acuson Sequoia, C256). High-sensitivity CRP was measured with Latex agglutination assay, sE-selectin and sICAM-1 were determined with ELISA.

RESULTS

Baseline characteristics were not different between groups. FMD improved in patients on atorvastatin (6.7+/-3.8% to 8.5+/-4.4%; p<0.01), but remained unchanged in placebo-treated patients (8.2+/-3.3% to 8.9+/-5.1%; p=NS). Atorvastatin treatment was associated with decreases of sICAM-1 (from 274.2+/-92.2 to 197.9+/-70.0 ng/ml; p<0.01) and hsCRP (from 0.57+/-0.45 to 0.18+/-0.15 mg/dl; p<0.01), whereas placebo treatment had no effect on these markers. sE-selectin levels were not influenced by either treatment. No correlations were found between changes in FMD, lipids and inflammatory markers.

CONCLUSIONS

Treatment with atorvastatin leads to an improvement in endothelial function and a reduction in inflammatory markers in patients with stable CAD. The lack of correlation between changes in FMD and inflammatory markers may support the concept of pleiotropic effects of statins in humans.

Statin therapy in cardiovascular diseases other than atherosclerosis

Statins are drugs that inhibit 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase, thereby blocking the synthesis of cholesterol. Since being discovered in Japan in the mid 1970s, statins have been widely used to lower low-density lipoprotein cholesterol. However, analysis of cardiovascular research has revealed other important effects beyond changes in lipid parameters, referred to as pleiotropic effects. This paper focuses on the effects of statins as anti-ischemic agents with improvement in endothelial function, along with studies on valvular aortic stenosis, atrial fibrillation, heart failure, peripheral arterial disease, and cancer. As the evolution of statin research continues, there appear to be new potential benefits from statins to be found in many facets of cardiovascular disease.

Effect of aggressive risk factor modification on cardiac events and myocardial ischaemia in patients with chronic kidney disease

OBJECTIVE

To examine whether aggressive risk factor modification in chronic kidney disease (CKD) can limit the development of new ischaemia or reduce cardiac events.

METHODS

Patients with CKD were randomly assigned to either an aggressive risk factor modification strategy (targeted treatment of hypertension, dyslipidaemia, homocysteine, haemoglobin and phosphate) or standard care. An intention to treat analysis was performed on 152 patients who had baseline dobutamine stress echocardiography (DSE), including 107 who had follow-up DSE. Biochemical parameters, cardiac risk factors and investigations (ECG, two-dimensional echocardiography) were recorded at baseline. New ischaemia was classed as new or worsening stress wall motion abnormality between follow-up and baseline DSE. Patients were followed up for the development of new ischaemia or cardiac death, acute coronary syndrome and non-fatal myocardial infarction over 1.8 years.

RESULTS

The development of new ischaemia was common but not different between the standard and aggressively treated groups (15 (21%) v 18 (23%), p = 0.8). Independent predictors of new ischaemia were older age, abnormal ECG, higher systolic blood pressure and lower serum high density lipoprotein cholesterol, but not treatment arm. The standard and aggressively treated groups did not differ in cardiac event rate (10% v 13%, p = 0.6) or all-cause mortality (10% v 19%, p = 0.2). In patients with an abnormal baseline DSE (non-diagnostic, scar or ischaemia), the event rate was similar (22% v 20%, p = 0.9).

CONCLUSION

Aggressive risk factor modification in CKD does not limit the development of new ischaemia or reduce cardiac events in patients with an abnormal DSE.

The statin studies: from targeting hypercholesterolaemia to targeting the high-risk patient

The landmark HMG-CoA reductase inhibitor (statin) studies have practical lessons for clinicans. The 4S trial established the importance of treating the hypercholesterolaemic patient with cardiovascular heart disease. Next, WOSCOPS showed the benefit of treating healthy, high-risk hypercholesterolaemic men. CARE, a secondary prevention trial, showed the benefit of treating patients with cholesterol levels within normal limits. This was confirmed by the LIPID trial, another secondary prevention study, which enrolled patients with cholesterol levels 155-271 mg/dl (4-7 mmol/l). The importance of treating patients with established ischaemic heart disease, and those at high risk of developing heart disease, regardless of cholesterol level, was being realized. In the MIRACL trial, hypocholesterolaemic therapy was useful in the setting of an acute coronary syndrome, while the AVERT study showed that aggressive statin therapy is as good as angioplasty in reducing ischaemic events in patients with stable angina. By showing the value of fluvastatin after percutaneous intervention, LIPS confirmed that benefit is a class action of the statins. The HPS randomized over 20 000 patients, and showed beyond doubt the value of statins in reducing cardiovascular events in the high-risk patient. Although PROSPER showed benefit in treating the elderly patients above 70 years, statin therapy in this trial was associated with an increase in cancer incidence. The comparative statin trials, PROVE-IT, REVERSAL, Phase Z of the A to Z, ALLIANCE and TNT, all showed that high-dose statins will better reduce cardiovascular events in the high-risk patient, although the adverse effects of therapy will also be increased. ALLHAT-LLT, ASCOT-LLA and CARDS showed that for statin therapy to demonstrate a significant benefit, hypertensive or diabetic patients must be at sufficiently high risk of cardiovascular events. The emphasis is now on the risk level for developing cardiovascular events, and treatment should target the high-risk group and not the lipid level of the patient. No therapy is free of adverse effect. Treatment of those most at risk will bring the most benefit; treatment of those not at high risk of cardiovascular disease may expose patients who would not benefit much from therapy to its adverse effects.

Effect of aggressive versus moderate lipid-lowering therapy on myocardial ischemia: the rationale, design, and baseline characteristics of the Study Assessing Goals in the Elderly (SAGE)

BACKGROUND

Patients with stable CHD who experience episodes of ischemia during routine daily activities are at increased risk of coronary events. Older patients are at a particularly high risk. Few trials have specifically investigated the effects of lipid-lowering therapy with statins in older patients.

METHODS

The SAGE trial is a prospective, randomized, double-blind, parallel-arm study enrolling men and women with stable CHD at 192 centers worldwide. Qualifying participants (aged 65-85 years; low-density lipoprotein cholesterol 100-250 mg/dL) have had at least 1 episode of myocardial ischemia with total ischemia duration >or=3 minutes on 48-hour ambulatory electrocardiographic (AECG) monitoring performed during routine daily activities. Participants have been randomized to either atorvastatin 80 mg/day (aggressive lipid lowering) or pravastatin 40 mg/day (moderate lipid lowering). The primary efficacy measure is the absolute change in the total duration of myocardial ischemic events on 48-hour AECG monitoring from baseline to month 12.

RESULTS

SAGE is fully enrolled and 893 patients have been randomized. The majority of the study participants are white (97%) men (69%). The mean age of the participants is 72 years. Most participants (94%) have a history of angina. Other high-risk patient groups included in the study are patients with hypertension (65%), patients with diabetes (23%), and patients with peripheral vascular disease (12%).

CONCLUSIONS

SAGE will evaluate the effect of aggressive versus moderate lipid lowering on the total duration of myocardial ischemia in older ambulatory patients with CHD. It is likely to provide valuable data on the benefits of statins in this patient population.

The effect of long-term aggressive lipid lowering on ischemic and atherosclerotic burden in patients with chronic kidney disease

BACKGROUND

Cardiac mortality is the main cause of death in patients with chronic kidney disease (CKD). In this study, we sought the efficacy of long-term intensive lipid level lowering on atherosclerotic burden in patients with CKD.

METHODS

Patients with CKD (n = 38; age, 64 +/- 11 years) and a similar group of patients with coronary artery disease (CAD; n = 31) were treated prospectively with atorvastatin, up to 80 mg/d. Lipid profile, carotid intima-media thickness (IMT; a marker of atherosclerotic burden), and dobutamine echocardiography were measured at baseline and 2 years. Predictors of change in maximal IMT were sought in a linear model.

RESULTS

Despite similar cholesterol level lowering, patients with CAD showed an improvement in maximum IMT, whereas those with CKD did not (mean between-group difference, 0.07 mm; 95% confidence interval, 0.01 to 0.12). Change in maximal IMT was associated with kidney disease (R2 = 0.09; P = 0.013), smoking (R2 = 0.083; P = 0.017), baseline low-density lipoprotein cholesterol (LDL-C) level (R2 = 0.064; P = 0.045), very low density cholesterol (VLDL-C) level (R2 = 0.084; P = 0.021), and calcium channel blocker use (R2 = 0.094; P = 0.01). In a multivariate model, kidney disease and baseline LDL-C and VLDL-C levels remained independent predictors of change in maximal IMT (model R2 = 0.24; P = 0.004). Only patients with CAD decreased their number of ischemic segments (2.5 +/- 1.4 to 1.2 +/- 1.5 segments; P = 0.002). Overall change in ischemic segment number correlated with change in maximal IMT (r = 0.32; P = 0.019).

CONCLUSION

Patients with CKD undergoing intensive lipid level lowering do not show the same changes in atherosclerotic or ischemic burden as patients with CAD. Independent predictors of change in maximal IMT were CKD and baseline LDL-C and VLDL-C levels.

The relative importance of vascular structure and function in predicting cardiovascular events

OBJECTIVES

We sought to assess the prognostic utility of brachial artery reactivity (BAR) in patients at risk of cardiovascular events.

BACKGROUND

Impaired flow-mediated vasodilation measured by BAR is a marker of endothelial dysfunction. Brachial artery reactivity is influenced by risk factors and is responsive to various pharmacological and other treatments. However, its prognostic importance is uncertain, especially relative to other predictors of outcome.

METHODS

A total of 444 patients were prospectively enrolled to undergo BAR and follow-up. These patients were at risk of cardiovascular events, based on the presence of risk factors or known or suspected cardiovascular disease. We took a full clinical history, performed BAR, and obtained carotid intima-media thickness (IMT) and left ventricular mass and ejection fraction. Patients were followed up for cardiovascular events and all-cause mortality. Multivariate Cox regression analysis was performed to assess the independent association of investigation variables on outcomes.

RESULTS

The patients exhibited abnormal BAR (5.2 +/- 6.1% [mean +/- SD]) but showed normal nitrate-mediated dilation (9.9 +/- 7.2%) and normal mean IMT (0.67 +/- 0.12 mm [average]). Forty-nine deaths occurred over the median follow-up period of 24 months (interquartile range 10 to 34). Patients in the lowest tertile group of BAR (<2%) had significantly more events than those in the combined group of highest and mid-tertiles (p = 0.029, log-rank test). However, mean IMT (rather than flow-mediated dilation) was the vascular factor independently associated with mortality, even in the subgroup (n = 271) with no coronary artery disease and low risk.

CONCLUSIONS

Brachial artery reactivity is lower in patients with events, but is not an independent predictor of cardiovascular outcomes in this cohort of patients.

Independent contribution of plaque complexity to myocardial ischemia during dobutamine stress echocardiography

The influence of complex plaque morphology on the extent of demand-induced ischemia in unselected patients is not well defined. We sought to investigate the functional significance of lesion morphology in patients who underwent coronary angiography and dobutamine stress echocardiography (DSE). Angiography and DSE were performed within a 6-month period (mean 1 +/- 1 month) in 196 patients. Angiographic assessments involved quantification of stenosis severity, assessment of the extent of jeopardized myocardium, and categorization of plaque morphology according to the Ambrose classification. DSE was interpreted by separate investigators with respect to wall motion score index (WMSI) and number of coronary territories involved. A general linear model was constructed to assess the independent contribution of patient characteristics and angiographic and DSE results with respect to extent of ischemic myocardium. Complex lesion morphology was seen in 62 patients (32%). Patients with complex lesions were more likely to have had prior myocardial infarction (p <0.001) and be current smokers (p = 0.03). During angiography, they exhibited a trend toward a greater number of diseased vessels, had a greater coronary jeopardy score (p <0.001) and more frequent collateral flow (p = 0.03). During echocardiography, patients had a higher stress WMSI (p <0.001) and were more likely to show ischemia in all 3 arterial territories (p <0.01). On multivariate regression, the coronary artery jeopardy score and the presence of complex plaque morphology were independent predictors of the extent of ischemic myocardium (R(2) = 34%, p <0.001). Thus, patients with complex plaque morphology are older, more likely to smoke, and more likely to have had prior myocardial infarction. They exhibit more extensive disease with higher coronary jeopardy scores and a higher resting and peak stress WMSI. Despite these differences, complex plaque morphology remains an independent predictor of the extent of ischemia during stress.