Effects of atorvastatin 80 mg daily early after onset of unstable angina pectoris or non-Q-wave myocardial infarction

Effect of More Intensive LDL-C-Lowering Therapy on Long-term Cardiovascular Outcomes in Early-Phase Acute Coronary Syndrome: A Systematic Review and Meta-analysis

PURPOSE

The effect of more intensive LDL-C-lowering therapy (ILLT) on long-term cardiovascular outcomes during the early phase of acute coronary syndromes (ACSs) remains uncertain. We aimed to explore the influence of more intensive LDL-C-lowering therapyduring the early disease phase on long-term cardiovascular events among patients with ACSs.

METHODS

Randomized controlled trials that focused on the effect of more ILLT during early-phase ACSs on long-term major adverse cardiac events (MACEs) were searched in electronic databases (MEDLINE, Embase, and Cochrane Central Register of Controlled Trials databases) from database inception until November 23, 2019. The end points included the incidence of MACEs, myocardial infarction, stroke, revascularization, heart failure, and death events. Study risk of bias was assessed using the Cochrane Collaboration tools. Fixed- or random-effects models and meta-regression were performed to evaluate the association between baseline/proportional reduction of LDL-C levels during early-phase disease and the risk of end points using risk ratios with 95% CIs.

FINDINGS

A total of 53,199 participants were involved from 19 studies. The risk of MACEs decreased by 17% (95% CI, 0.76-0.90; P = 0.0012) for more intensive versus control therapy but varied by baseline and proportional reduction of LDL-C levels during early disease phase. The risk reduction of MACEs for more intensive versus control therapy among different subgroups was 26% (95% CI, 0.57-0.95; P = 0.06) with a baseline level >130 mg/dL, 23% (95% CI, 0.63-0.94; P = 0.02) with a baseline level of 100 to 130 mg/dL, and 10% (95% CI, 0.83-0.99; P = 0.07) with a baseline level <100 mg/dL. A significant difference of risk reduction for MACEs existed between patients treated with statin plus ezetimibe versus statin alone in the subgroup with a baseline level >130 mg/dL and proportional reduction >50%. Patients treated with more intensive therapy benefited from reduced risk of myocardial infarction, stroke, revascularization, and heart failure compared with control therapy.

IMPLICATIONS

More ILLT during early disease phase could significantly reduce the risk of long-term cardiovascular outcome in patients with ACSs. This benefit was most pronounced in patients with higher baseline and larger reduction of LDL-C levels in MACEs.

High-intensity statin therapy yields better outcomes in acute coronary syndrome patients: a meta-analysis involving 26,497 patients

Background

Whether high-intensity statin treatment provides more clinical benefits compared with standard statin regimens in acute coronary syndrome (ACS) patients remains controversial. This meta-analysis aimed to comparatively assess high-intensity and standard statin regimens for efficacy and safety in patients with ACS.

Methods

The PubMed, EMBASE, and Cochrane Library databases were searched for studies assessing high-intensity vs. standard statin regimens for ACS treatment from inception to April 2020. The publication language was limited to English, and 16 randomized controlled trials were finally included in this study, with a total of 26,497 patients.

Results

Compared to the standard statin regimens, the relative ratio (RR) of major adverse cardiovascular events (MACE) in ACS patients treated by high-intensity statin was 0.77 (95%CI, 0.68–0.86; P < 0.00001; prediction interval, 0.56–1.07). In subgroup analysis, high-intensity statin therapy resulted in more clinical benefits regarding MACE compared with standard statin treatment in both Asian (RR = 0.77; 95%CI, 0.61–0.98; P = 0.03) and non-Asian (RR = 0.79; 95%CI, 0.71–0.89; P < 0.0001) patients. Although adverse events were acceptable in patients with ACS administered high-intensity statin therapy, this treatment was associated with a higher rate of adverse events (4.99% vs. 2.98%), including myopathy/myalgia and elevated liver enzymes, as reflected by elevated serum aminotransferase or aminotransferase amounts.

Conclusion

The current findings indicated that high-intensity statin therapy might be beneficial in patients with ACS, and close monitoring for adverse effects should be performed.

Statin use and the risk of developing diabetes: a network meta-analysis

PURPOSE

Randomized controlled trials have shown mixed findings regarding the association of statins and diabetes. This systematic literature review and network meta-analysis (NMA) was performed to update evidence on this association to possibly assist clinicians in making more informed treatment choices.

METHODS

We identified studies relevant to our NMA by performing study searches in databases like Embase, Cochrane, and PubMed, published between August 2010 and June 2014. Pre-2010 studies were identified from bibliography of previously published meta-analyses. Unpublished study data were found from clinicaltrial.gov. Data synthesis was performed by pairwise meta-analysis and NMA within a Frequentist framework.

RESULTS

Twenty nine trials in which 1 63 039 participants had been randomized were included in this review; among these 1 41 863 were non-diabetic patients. The direct meta-analysis showed that statins, as a class, significantly increased the likelihood of developing diabetes by 12% (pooled OR 1.12; 95%CI 1.05-1.21; I² 36%; p = 0.002; 18 RCTs). In the NMA, atorvastatin 80 mg was associated with a highest risk of diabetes, with OR of 1.34 (95%CI 1.14-1.57) followed by rosuvastatin (OR: 1.17; 95%CI: 1.02-1.35). The ORs (95%CIs) for simvastatin 80 mg, simvastatin, atorvastatin, pravastatin, lovastatin and pitavastatin were 1.21 (0.99-1.49), 1.13 (0.99-1.29), 1.13 (0.94-1.34), 1.04 (0.93-1.16), 0.98 (0.69-1.38) and 0.74 (0.31-1.77), respectively. High-dose atorvastatin increased the odds of developing diabetes even when compared with pravastatin, simvastatin and low-dose atorvastatin in the NMA.

CONCLUSIONS

Based on the results, statins, as a class, increased the risk of diabetes significantly in the pairwise meta-analysis. Overall, there appears to be a small increased risk of incident diabetes, particularly with more intensive statin therapy, although more data would be valuable to increase the robustness of this interpretation, given that the lower confidence intervals of our study analyses are close to, or just crossing one. Copyright © 2016 John Wiley & Sons, Ltd.

Protective and pathological roles of tissue factor in the heart

Tissue factor (TF) is expressed in the heart where it is required for haemostasis. High levels of TF are also expressed in atherosclerotic plaques and likely contribute to atherothrombosis after plaque rupture. Indeed, risk factors for atherothrombosis, such as diabetes, hypercholesterolaemia, smoking and hypertension, are associated with increased TF expression in circulating monocytes, microparticles and plasma. Several therapies that reduce atherothrombosis, such as statins, ACE inhibitors, beta-blockers and anti-platelet drugs, are associated with reduced TF expression. In addition to its haemostatic and pro-thrombotic functions, the TF : FVIIa complex and downstream coagulation proteases activate cells by cleavage of protease-activated receptors (PARs). In mice, deficiencies in either PAR-1 or PAR-2 reduce cardiac remodelling and heart failure after ischaemia-reperfusion injury. This suggests that inhibition of coagulation proteases and PARs may be protective in heart attack patients. In contrast, the TF/thrombin/PAR-1 pathway is beneficial in a mouse model of Coxsackievirus B3-induced viral myocarditis. We found that stimulation of PAR-1 increases the innate immune response by enhancing TLR3-dependent IFN-β expression. Therefore, inhibition of the TF/thrombin/PAR-1 pathway in patients with viral myocarditis could have detrimental effects.

CONCLUSION

The TF : FVIIa complex has both protective and pathological roles in the heart.

Statins for acute coronary syndrome

BACKGROUND

The early period following the onset of acute coronary syndrome (ACS) represents a critical stage of coronary heart disease, with a high risk of recurrent events and deaths. The short-term effects of early treatment with statins on patient-relevant outcomes in patients suffering from ACS are unclear. This is an update of a review previously published in 2011.

OBJECTIVES

To assess the effects, both harms and benefits, of early administered statins in patients with ACS, in terms of mortality and cardiovascular events.

SEARCH METHODS

We updated the searches of CENTRAL (2013, Issue 3), MEDLINE (Ovid) (1946 to April Week 1 2013), EMBASE (Ovid) (1947 to 2013 Week 14), and CINAHL (EBSCO) (1938 to 2013) on 12 April 2013. We applied no language restrictions. We supplemented the search by contacting experts in the field, by reviewing the reference lists of reviews and editorials on the topic, and by searching trial registries.

SELECTION CRITERIA

Randomized controlled trials (RCTs) comparing statins with placebo or usual care, with initiation of statin therapy within 14 days following the onset of ACS, follow-up of at least 30 days, and reporting at least one clinical outcome.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed risk of bias and extracted data. We calculated risk ratios (RRs) for all outcomes in the treatment and control groups and pooled data using random-effects models.

MAIN RESULTS

Eighteen studies (14,303 patients) compared early statin treatment versus placebo or no treatment in patients with ACS. The new search did not identify any new studies for inclusion. There were some concerns about risk of bias and imprecision of summary estimates. Based on moderate quality evidence, early statin therapy did not decrease the combined primary outcome of death, non-fatal myocardial infarction, and stroke at one month (risk ratio (RR) 0.93, 95% confidence interval (CI) 0.80 to 1.08) or four months (RR 0.93, 95% CI 0.81 to 1.06) of follow-up when compared to placebo or no treatment. There were no statistically significant risk reductions from statins for total death, total myocardial infarction, total stroke, cardiovascular death, revascularization procedures, and acute heart failure at one month or at four months, although there were favorable trends related to statin use for each of these endpoints. Moderate quality evidence suggests that the incidence of unstable angina was significantly reduced at four months following ACS (RR 0.76, 95% CI 0.59 to 0.96). There were nine individuals with myopathy (elevated creatinine kinase levels more than 10 times the upper limit of normal) in statin-treated patients (0.13%) versus one (0.015%) in the control groups. Serious muscle toxicity was mostly limited to patients treated with simvastatin 80 mg.

AUTHORS' CONCLUSIONS

Based on moderate quality evidence, due to concerns about risk of bias and imprecision, initiation of statin therapy within 14 days following ACS does not reduce death, myocardial infarction, or stroke up to four months, but reduces the occurrence of unstable angina at four months following ACS. Serious side effects were rare.

A users' guide to understanding therapeutic substitutions

Therapeutic substitutions are common at the level of ministries of health, clinicians, and pharmacy dispensaries. Guidance in determining whether drugs offer similar risk-benefit profiles is limited. Those making decisions on therapeutic substitutions should be aware of potential biases that make differentiating therapeutic agents difficult. Readers should consider whether the biological mechanisms and doses are similar across agents, whether the evidence is sufficiently valid across agents, and whether the safety and therapeutic effects of each drug are similar. This article uses a problem-based format to address the biological mechanism, validity, and results of a scenario in which therapeutic substitutions may be considered.

Effect of pretreatment with simvastatin on spinal cord ischemia-reperfusion injury in rats

OBJECTIVE

The aim of this study was to evaluate the pretreatment effect of simvastatin on spinal cord ischemia-reperfusion injury.

DESIGN

Prospective, interventional study.

SETTING

University research laboratory.

PARTICIPANTS

Forty-five male Sprague-Dawley rats.

INTERVENTIONS

Rats were treated with oral simvastatin, 10 mg/kg (simvastatin group; n = 15) or saline (control group; n = 15) for 5 days before ischemia. Spinal cord ischemia was induced using a balloon-tipped catheter placed in the proximal descending aorta in the control and simvastatin groups, but not in the sham group (n = 15).

MEASUREMENTS AND MAIN RESULTS

Neurologic function was assessed daily using the motor deficit index until 7 days after reperfusion. After the last neurologic evaluation, a histologic examination of the spinal cord was performed. At day 1 after reperfusion, the simvastatin group showed a significantly lower motor deficit index compared with the control group (2.0, 2.0-2.0, v 4.0, 3.5-5.0; p < 0.001). This trend was sustained at day 7 (2.0, 1.5-2.0, v 4.0, 3.0-4.0; p < 0.001). The simvastatin group displayed a significantly larger number of normal motor neurons compared with the control group (mean ± SD, 31.7 ± 6.1 v 20.4 ± 4.4; p < 0.001). However, compared with the sham group, the simvastatin group displayed fewer intact motor neurons (sham group, 38.5 ± 5.1; p = 0.005).

CONCLUSIONS

Pretreatment with simvastatin, 10 mg/kg, given orally for 5 days before the ischemia-reperfusion insult, improved the neurologic outcome and preserved more normal motor neurons compared with the control group in a rat model of spinal cord ischemia-reperfusion.

Bias in observational studies of prevalent users: lessons for comparative effectiveness research from a meta-analysis of statins

Randomized clinical trials (RCTs) are usually the preferred strategy with which to generate evidence of comparative effectiveness, but conducting an RCT is not always feasible. Though observational studies and RCTs often provide comparable estimates, the questioning of observational analyses has recently intensified because of randomized-observational discrepancies regarding the effect of postmenopausal hormone replacement therapy on coronary heart disease. Reanalyses of observational data that excluded prevalent users of hormone replacement therapy led to attenuated discrepancies, which begs the question of whether exclusion of prevalent users should be generally recommended. In the current study, the authors evaluated the effect of excluding prevalent users of statins in a meta-analysis of observational studies of persons with cardiovascular disease. The pooled, multivariate-adjusted mortality hazard ratio for statin use was 0.77 (95% confidence interval (CI): 0.65, 0.91) in 4 studies that compared incident users with nonusers, 0.70 (95% CI: 0.64, 0.78) in 13 studies that compared a combination of prevalent and incident users with nonusers, and 0.54 (95% CI: 0.45, 0.66) in 13 studies that compared prevalent users with nonusers. The corresponding hazard ratio from 18 RCTs was 0.84 (95% CI: 0.77, 0.91). It appears that the greater the proportion of prevalent statin users in observational studies, the larger the discrepancy between observational and randomized estimates.

Adverse events associated with individual statin treatments for cardiovascular disease: an indirect comparison meta-analysis

BACKGROUND

Statins are the most widely prescribed drug available. Due to this reason, it is important to understand the risks involved with the drug class and individual statins.

AIM

We conducted a meta-analysis and employed indirect comparisons to identify differing risk effects across statins.

DESIGN

We included any randomized clinical trial (RCT) of atorvastatin, fluvastatin, lovastatin, pitavastatin, pravastatin, rosuvastatin and simvastatin used for cardiovascular disease event prevention. The main outcome was adverse events [all-cause mortality, cancers, rhabdomylosis, diabetes, aspartate and alanine aminotransferase (AST/ALT), and creatinine kinase (CK) increases beyond the upper limit of normal]. In order to evaluate the relative effects of each drug on adverse events, we calculated adjusted indirect comparisons of the adverse-event outcomes.

RESULTS

Seventy-two trials involving 159,458 patients met our inclusion criteria. Overall, statin treatments significantly increased the rate of diabetes when compared to controls (OR: 1.09; 95% CI: 1.02-1.16) and elevated AST (OR: 1.31; 95% CI: 1.04-1.66) and ALT (OR: 1.28; 95% CI: 1.11-1.48) levels when compared to controls. Using indirect comparisons, we also found that atorvastatin significantly elevated AST levels compared to pravastatin (OR: 2.21; 95% CI: 1.13-4.29) and simvastatin significantly increased CK levels when compared to rosuvastatin (OR: 4.39; 95% CI: 1.01-19.07). Higher dose studies had increased risk of AST elevations.

DISCUSSION

Although statins are generally well tolerated, there are risks associated with almost all drugs. With few exceptions, statins appear to exert a similar risk across individual drugs.

Statins for acute coronary syndrome

BACKGROUND

The early period following the onset of acute coronary syndromes (ACS) represents a critical stage of coronary heart disease with a high risk for recurrent events and deaths. The short-term effects of early treatment with statins in patients suffering from ACS on patient-relevant outcomes are unclear.

OBJECTIVES

To assess the benefits and harms of early administered statins in patients with ACS from randomized controlled trials (RCTs).

SEARCH STRATEGY

We searched CENTRAL, MEDLINE, EMBASE, and CINAHL (to 1 February 2010). No language restrictions were applied. We supplemented the search by contacting experts in the field, by reviewing reference lists of reviews and editorials on the topic, and by searching trial registries.

SELECTION CRITERIA

RCTs comparing statins with placebo or usual care, initiation of statin therapy within 14 days following the onset of ACS, and follow-up of at least 30 days reporting at least one clinical outcome.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed study quality and extracted data. We pooled treatment effects and calculated risk ratios (RRs) for all outcomes in the treatment and control groups using a random effects model.

MAIN RESULTS

Eighteen studies (14,303 patients) compared early statin treatment versus placebo or usual care in patients with ACS. Compared to placebo or usual care, early statin therapy did not decrease the combined primary outcome of death, non-fatal myocardial infarction (MI), and stroke at one month (risk ratio (RR) 0.93, 95% confidence interval (CI) 0.80 to 1.08) and four months (RR 0.93, 95% CI 0.81 to 1.06) of follow-up. There were no statistically significant risk reductions from statins for total death, total MI, total stroke, cardiovascular death, revascularization procedures, and acute heart failure at one month and at four months, although there were favorable trends related to statin use for each of these endpoints. The incidence of episodes of unstable angina was significantly reduced at four months following ACS (RR 0.76, 95% CI 0.59 to 0.96). There were nine individuals with myopathy (elevated creatinine kinase levels > 10 times the upper limit of normal) in statin treated patients (0.13%) versus one (0.015%) in the control groups. Serious muscle toxicity was mostly limited to patients treated with simvastatin 80 mg.

AUTHORS' CONCLUSIONS

Based on available evidence, initiation of statin therapy within 14 days following ACS does not reduce death, myocardial infarction, or stroke up to four months, but reduces the occurrence of unstable angina at four months following ACS.

Updated evidence on early statin therapy for acute coronary syndromes: meta-analysis of 18 randomized trials involving over 14,000 patients

BACKGROUND

The short-term effects of early statin therapy in acute coronary syndromes (ACS) on clinical outcomes remain unclear. Our objective was to update the evidence on patient relevant outcomes from all randomized trials comparing early statin therapy with placebo or usual care at 1 and 4 months following ACS.

METHODS

We performed a systematic review and meta-analysis of randomized trials that compared statins to control, initiated within 14 days after onset of ACS and with minimal follow-up of 30 days. Data were extracted in duplicate and analyzed by a random effects model. Investigators from individual trials contributed additional data where needed.

RESULTS

A total of 18 trials involving 14,303 patients with ACS were included in the meta-analysis. We found no evidence for further trials on the topic. Risk ratios for the combined endpoint of death, myocardial infarction, and stroke of early statin therapy compared to control were 0.93 (95% confidence interval [CI], 0.80-1.08; P=0.34) at 1 month and 0.93 (95% CI, 0.81-1.06; P=0.27) at 4 months following ACS. There were favorable trends related to statin use for all individual secondary endpoints but there was no statistically significant risk reduction except for unstable angina with a risk ratio of 0.76 (95% CI, 0.59-0.96; P=0.02) at 4 months following ACS.

CONCLUSIONS

Initiation of statin therapy within 14 days following ACS results in directionally favorable but non-significant reduction in death, myocardial infarction, or stroke up to 4 months, and significant reduction in the occurrence of unstable angina at 4 months following ACS.

Efficacy and safety of statin treatment for cardiovascular disease: a network meta-analysis of 170,255 patients from 76 randomized trials

BACKGROUND

Statins represent the largest selling class of cardiovascular drug in the world. Previous randomized trials (RCTs) have demonstrated important clinical benefits with statin therapy.

AIM

We combined evidence from all RCTs comparing a statin with placebo or usual care among patients with and without prior coronary heart disease (CHD) to determine clinical outcomes.

DESIGN

We searched independently, in duplicate, 12 electronic databases (from inception to August 2010), including full text journal content databases, to identify all statin versus inert control RCTs. We included RCTs of any statin versus any non-drug control in any populations. We abstracted data in duplicate on reported major clinical events and adverse events. We performed a random-effects meta-analysis and meta-regression. We performed a mixed treatment comparison using Bayesian methods.

RESULTS

We included a total of 76 RCTs involving 170,255 participants. There were a total of 14,878 deaths. Statin therapy reduced all-cause mortality, Relative Risk (RR) 0.90 [95% confidence interval (CI) 0.86-0.94, P ≤ 0.0001, I(2)=17%]; cardiovascular disease (CVD) mortality (RR 0.80, 95% CI 0.74-0.87, P<0.0001, I(2)=27%); fatal myocardial infarction (MI) (RR 0.82, 95% CI 0.75-0.91, P<0.0001, I(2)=21%); non-fatal MI (RR 0.74, 95% CI 0.67-0.81, P ≤ 0.001, I(2)=45%); revascularization (RR 0.76, 95% CI 0.70-0.81, P ≤ 0.0001); and a composite of fatal and non-fatal strokes (0.86, 95% CI 0.78-0.95, P=0.004, I(2)=41%). Adverse events were generally mild, but 17 RCTs reported on increased risk of development of incident diabetes [Odds Ratio (OR) 1.09; 95% CI 1.02-1.17, P=0.001, I(2)=11%]. Studies did not yield important differences across populations. We did not find any differing treatment effects between statins.

DISCUSSION

Statin therapies offer clear benefits across broad populations. As generic formulations become more available efforts to expand access should be a priority.

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.

Long-term benefit of statin therapy initiated during hospitalization for an acute coronary syndrome: a systematic review of randomized trials

OBJECTIVE

This study sought to determine if the initiation of statin (HMG-CoA reductase inhibitor) therapy during acute coronary syndromes reduces long-term mortality and other adverse cardiac outcomes.

BACKGROUND

Initiation of statin therapy during acute coronary syndromes has not been shown to reduce mortality, myocardial infarction or stroke within 4 months of follow-up.

METHODS

Clinical trials that randomized patients with acute coronary syndromes to early statin therapy compared with less intensive lipid reduction (placebo/lower-dose statin/usual care), and reported long-term outcomes were included for analysis.

RESULTS

In all, there were seven studies (L-CAD, PTT, FLORIDA, Colivicchi et al., PROVE-IT, ESTABLISH, and A-to-Z) with 9553 patients who started statin therapy within 12 days of hospital presentation. The incidence of all-cause mortality was 3.4% in the statin group versus 4.6% in the less intensive lipid reduction group over a weighted mean follow-up of 22.9 months (relative risk [RR] 0.74; 95% CI 0.61, 0.90; p = 0.003). The number of patients needed to treat to prevent one death was 84 patients. Similarly, the incidence of cardiovascular mortality in the statin versus the less intensive lipid reduction group was 2.4% versus 3.3% (RR 0.74; 95% CI 0.58, 0.93; p = 0.010), unstable angina 4.1% versus 5.0% (RR 0.81; 95% CI 0.68, 0.98; p = 0.027), revascularization 11.2% versus 12.9% (RR 0.86; 95% CI 0.78, 0.96; p = 0.006), stroke 1.1% versus 1.2% (RR 0.90; 95% CI 0.62, 1.30; p = 0.56), and myocardial infarction 6.6% versus 7.0% (RR 0.94; 95% CI 0.81, 1.09; p = 0.41).

CONCLUSIONS

The benefit of early initiation of statin therapy during acute coronary syndromes slowly accrues over time so that a survival advantage is seen around 24 months. Relatively few patients need to be treated to prevent one death over this time period. Furthermore, this approach significantly reduces unstable angina and the need for revascularization.

Lipid-lowering therapy with statins, a new approach to antiarrhythmic therapy

Inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase (statins) are the most effective and best-tolerated drugs to treat elevated levels of low-density lipoprotein cholesterol (LDL-C). In addition, they exhibit other effects unrelated to their lipid lowering effects (pleiotropic actions). In recent years, experimental and clinical evidence demonstrates that statins exert antiarrhythmic properties, reducing the recurrences of supraventricular and life-threatening ventricular arrhythmias both in patients with and without coronary artery disease (CAD). Thus, statins may constitute a novel therapeutic approach to cardiac arrhythmias. This article reviews the antiarrhythmic properties of statins as well as the possible mechanisms involved, including the lowering of LDL-C levels, the improvement of endothelial dysfunction and autonomic function, the stabilization of the atherosclerotic plaques, the antioxidant, antiinflammatory, antithrombotic and cardioprotective properties and the modulation of transmembrane ion fluxes.

Association between time of statin initiation after hospital discharge from acute myocardial infarction and risk of recurrence and mortality in patients > or =65 years of age

Clinical studies have shown the benefit of statin use after acute myocardial infarction (AMI). However, it is uncertain how this benefit relates to the timing of statin initiation after AMI. We created a retrospective cohort (from 1996 to 2001) using health care databases in Quebec, Canada, to study patients (> or =65 years of age) who had AMI and differed in time of statin initiation within the first 90 days after discharge. Rates of recurrent AMI and mortality were compared between patients who initiated statins at discharge (early group) and those who initiated statins 1 month later and up to 90 days after discharge (delayed group). A multivariate Cox's regression model was used in the comparison. We used prescription time distribution matching to control for survival difference between groups. The early and delayed groups consisted of 3,075 and 1,187 patients, respectively. During the 1-year follow-up, there was no evidence to suggest a difference in outcome between groups. Adjusted hazard ratios for early versus delayed initiation were 1.03 (95% confidence interval 0.56 to 1.87) at 3 months and 1.24 (95% confidence interval 0.96 to 1.62) at 1 year. Analyses that were restricted to first-time statin users or excluded patients who had severe co-morbidity or were > or =85 years old did not change the results. Our findings were not affected by changing the definition of delayed use within the 90-day period. In conclusion, delay of statin initiation up to 30 to 90 days after discharge after AMI does not appear to lead to a difference in the rates of recurrent AMI and mortality compared with statin initiation at discharge.

Fourteen-year (1987 to 2000) trends in the attack rates of, therapy for, and mortality from non-ST-elevation acute coronary syndromes in four United States communities

During the past 2 decades, randomized trials have proved the efficacy of several treatments for non-ST-elevation acute coronary syndromes (NSTE-ACSs), including aspirin, beta blockers, and coronary revascularization. However, the cumulative effectiveness of these evolving therapies in actual clinical practice remains unknown. The Atherosclerosis Risk In Communities (ARIC) surveillance study uses rigorous prospective community surveillance to monitor the epidemiology of coronary heart disease among subjects who are 35 to 74 years of age and reside in 4 United States communities, with a population totaling 370,000 subjects. We identified 6,379 ARIC surveillance patients who were hospitalized with NSTE-ACS (defined as cardiac chest pain and ST depression or T-wave inversion on the presenting electrocardiogram) between 1987 and 2000 and then analyzed 30-day and 1-year mortalities by calendar year of admission. Using logistic regression, 30-day mortality was modeled first using predictor variables of the calendar year, ARIC community, and indicators of severity and co-morbidity and then by adding variables for treatment with aspirin, beta blockers, and coronary revascularization to this model. Crude 30-day mortality decreased from 8.6% in 1988 to 3.6% in 2000 (p for trend <0.001), a trend that remained significant (p = 0.006) after adjustment for case severity and co-morbidity. The trend became nonsignificant after adjustment for treatment variables, suggesting that newer treatments may explain the improved survival. In conclusion, 30-day mortality from NSTE-ACS has decreased as treatment has improved.

Immediate Effects of Fluvastain on Circulating Soluble Endothelial Protein C and Free Tissue Factor Pathway Inhibitor in Acute Coronary Syndromes

BACKGROUND

Statins promptly lower rates of adverse cardiovascular events in patients with acute coronary syndromes (ACS). These therapeutic properties may be mediated by the effects of statins on key hemostatic factors. This study examined the immediate effects of fluvastatin on plasma free tissue factor pathway inhibitor (fTFPI) and soluble endothelial protein C receptor (sEPCR) concentrations in patients with unstable angina or non-ST segment elevation myocardial infarction.

METHODS

We studied 57 patients consecutively admitted to our emergency department and randomly assigned to placebo (n = 29) versus fluvastatin, 80 mg, p.o. (n = 28). All patients were treated with aspirin and metoprolol p.o., nitroglycerin i.v., and subcutaneous enoxaparin. Venous blood was sampled as soon as possible upon admission, before and 6 h after administration of study drug and standard anti-ischemic therapy.

RESULTS

Mean sEPCR concentrations decreased significantly in patients treated with fluvastatin (-8.1 +/- 6.7% from baseline) and was unchanged in the placebo group (-2.3 +/- 14.4%, P = 0.007 vs. fluvastatin). Though fTFPI increased significantly after the administration of both fluvastatin and placebo, the mean increase after fluvastatin (450+/-436%) was significantly greater than after placebo (155+/-141%, P = 0.001).

CONCLUSIONS

Treatment with fluvastatin significantly modified key hemostatic factors toward an antithrombotic effect within 6 h. These properties may, in part, explain the early salutary effects of fluvastatin in patients with ACS.

Anti-inflammatory effect of atorvastatin (80 mg) in unstable angina pectoris and non-Q-wave acute myocardial infarction

In this randomized trial, C-reactive protein increased during the first 5 days of an acute coronary syndrome in patients treated with placebo, but this phenomenon was not observed in those randomized to atorvastatin 80 mg/day. This suggests that short-term statin therapy inhibits inflammation in patients with non-ST-elevation acute coronary syndromes.

Prothrombotic and antithrombotic pathways in acute coronary syndromes

The acute coronary syndromes arise from procoagulant changes in complex plaques, which trigger both platelet activation and coagulation pathways. These 2 pathways intersect at a number of points that form positive-feedback loops to sustain and accelerate thrombus formation. In normal hemostasis and with a healthy endothelium, intravascular thrombosis is prevented, and vascular patency is protected by the fibrinolytic system and a number of antithrombotic factors, such as antithrombin, thrombomodulin, and tissue factor pathway inhibitor. However, atherosclerosis is characterized by a hypercoagulable state, and the fibrinolytic balance is skewed toward occlusive thrombus formation at critical sites on vulnerable plaques. This review focuses on cellular and humoral mechanisms and the antithrombotic strategies that are important during the acute phase of an ischemic coronary syndrome, both in patients managed conservatively and in patients scheduled for an interventional procedure. These strategies include fibrinolytic therapy, antiplatelet therapies (aspirin, clopidogrel, glycoprotein IIb/IIIa receptor inhibitors), and low-molecular-weight heparin.