2011 ACCF/AHA Focused Update of the Guidelines for the Management of Patients With Unstable Angina/Non–ST-Elevation Myocardial Infarction (Updating the 2007 Guideline)

Potential role of rivaroxaban in patients with acute coronary syndrome

Patients with acute coronary syndrome (ACS) continue to be at risk for recurrent ischemic events, despite an early invasive strategy and the use of dual antiplatelet therapy. The anticoagulant pathway remains activated for a prolonged period after ACS and, consequently, has been a target for treatment. Early studies with warfarin indicated its benefit, but the risk of bleeding and the complexities of warfarin anticoagulation resulted in little use of this strategy. Rivaroxaban, apixaban, and dabigatran are new specific inhibitors of anticoagulant factors (Xa or IIa) currently available for the prevention of thrombosis and/or thromboembolism. Thus far, studies with dabigatran and apixaban in ACS have shown no clinical benefit and bleeding has been increased. The ATLAS ACS 2-TIMI 51 trial observed the impact of rivaroxaban 2.5 mg and 5 mg twice daily in patients with recent ACS receiving current management (both early invasive strategy and dual antiplatelet therapy with aspirin and clopidogrel) over a follow-up period of over 1 year. Rivaroxaban 2.5 mg twice daily reduced cardiovascular death, myocardial infarction, or stroke by 16%, and both cardiovascular and all-cause mortality by approximately 20%. Although major bleeding increased from 0.6% to 2.1% and intracranial hemorrhage from 0.2% to 0.6%, there was no increase in fatal bleeding. The role of rivaroxaban in the management of ACS is discussed in this review. The reduction in mortality is the main finding that could lead to the use of rivaroxaban in the management of ACS in high-risk individuals with a low bleeding risk.

Acute coronary syndrome in patients with diabetes mellitus: perspectives of an interventional cardiologist

Diabetes mellitus (DM) is well known to be a coronary artery disease risk equivalent but the cellular mechanism is not completely understood. Recently, virtual histology intravascular ultrasound has demonstrated that patients with DM tend to have a higher occurrence of vulnerable plaques as compared with patients without DM. Insulin-sensitizing agents, such as metformin, have been shown to have limited cardioprotective effects, whereas thiazolidinediones, such as rosiglitazone, have been reported to have possible deleterious effects on cardiovascular mortality in a meta-analysis; however, limited data exist. In contrast, pioglitazone has been reported to have a significant benefit in patients with type 2 DM with acute coronary syndrome (ACS). Animal and human studies have demonstrated the myocardial protective effects of incretins and hold promise in reducing the incidence of major adverse cardiac events in patients with DM. Moreover, in addition to aspirin, the early use of potent antiplatelet agents, such as prasugrel and intravenous glycoprotein IIb-IIIa inhibitors, in patients with DM presenting with ACS is crucial for reducing cardiovascular events in most patients. Thus, patients with DM deserve special attention in global risk factor reduction and development of newer therapeutic agents to improve glycemic control while minimizing or reducing cardiovascular events. This article focuses on ACS in patients with DM, the pathophysiology of "vulnerable blood" in patients with DM, and newer treatment strategies to improve outcomes in this high-risk patient population.

Acute coronary syndromes: from the emergency department to the cardiac care unit

Acute coronary syndromes result in a significant burden of morbidity and mortality in the United States. This spectrum of acute coronary thrombosis (including unstable angina, non-ST-segment elevation myocardial infarction, and ST-elevation myocardial infarction) has been well studied in large clinical trials. This review details the initial management of patients presenting with possible acute coronary syndromes in the context of care from the emergency department to the cardiac care unit. The importance of a rapid and focused evaluation, risk stratification, and appropriate therapies are discussed.

ABCB1 C3435T polymorphism and response to clopidogrel treatment in coronary artery disease (CAD) patients: a meta-analysis

BACKGROUND

A number of investigators have evaluated the association between the ABCB1 polymorphism and clopidogrel responding, but the results have been inconclusive. To examine the risk of high platelet activity and poor clinical outcomes associated with the ABCB1 C3435T polymorphism in CAD patients on clopidogrel, all available studies were included in the present meta-analysis.

METHODS

We performed a systematic search of PubMed, Scopus and the Cochrane library database for eligible studies. Articles meeting the inclusion criteria were comprehensively reviewed, and the available data were accumulated by the meta-analysis.

RESULTS

It was demonstrated that the ABCB1 C3435T variation was associated with the risk of early major adverse cardiovascular events (MACE) (T vs. C OR, 1.34; 95% CI, 1.10 to 1.62; P=0.003; TT vs. CC: OR, 1.77; 95% CI, 1.19 to 2.63; P=0.005; CT + TT vs.CC: OR, 1.48; 95% CI, 1.06 to 2.06; P=0.02) and the polymorphism was also associated with the risk of the long-term MACE in patients on clopidogrel LD 300 mg (T vs. C: OR, 1.28; 95% CI, 1.10 to 1.48; P=0.001; TT vs. CC: OR, 1.59; 95% CI, 1.19 to 2.13; P=0.002; CT + TT vs.CC: OR, 1.39; 95% CI, 1.08 to 1.79; P=0.01). The comparison of TT vs. CC was associated with a reduction in the outcome of bleeding (TT vs. CC: OR, 0.51; 95% CI, 0.40 to 0.66; P<0.00001). However, the association between ABCB1 C3435T polymorphism and platelet activity and other risk of poor clinical outcomes was not significant.

CONCLUSIONS

The evidence from our meta-analysis indicated that the ABCB1 C3435T polymorphism might be a risk factor for the MACE in patients on clopidogrel LD 300 mg, and that TT homozygotes decreased the outcome of bleeding compared with CC homozygotes.

Prasugrel versus clopidogrel for acute coronary syndromes without revascularization

BACKGROUND

The effect of intensified platelet inhibition for patients with unstable angina or myocardial infarction without ST-segment elevation who do not undergo revascularization has not been delineated.

METHODS

In this double-blind, randomized trial, in a primary analysis involving 7243 patients under the age of 75 years receiving aspirin, we evaluated up to 30 months of treatment with prasugrel (10 mg daily) versus clopidogrel (75 mg daily). In a secondary analysis involving 2083 patients 75 years of age or older, we evaluated 5 mg of prasugrel versus 75 mg of clopidogrel.

RESULTS

At a median follow-up of 17 months, the primary end point of death from cardiovascular causes, myocardial infarction, or stroke among patients under the age of 75 years occurred in 13.9% of the prasugrel group and 16.0% of the clopidogrel group (hazard ratio in the prasugrel group, 0.91; 95% confidence interval [CI], 0.79 to 1.05; P=0.21). Similar results were observed in the overall population. The prespecified analysis of multiple recurrent ischemic events (all components of the primary end point) suggested a lower risk for prasugrel among patients under the age of 75 years (hazard ratio, 0.85; 95% CI, 0.72 to 1.00; P=0.04). Rates of severe and intracranial bleeding were similar in the two groups in all age groups. There was no significant between-group difference in the frequency of nonhemorrhagic serious adverse events, except for a higher frequency of heart failure in the clopidogrel group.

CONCLUSIONS

Among patients with unstable angina or myocardial infarction without ST-segment elevation, prasugrel did not significantly reduce the frequency of the primary end point, as compared with clopidogrel, and similar risks of bleeding were observed. (Funded by Eli Lilly and Daiichi Sankyo; TRILOGY ACS ClinicalTrials.gov number, NCT00699998.).

Current antiplatelet options for NSTE-ACS patients

Non-ST elevation (NSTE) myocardial infarction and unstable angina are the most common clinical presentations of acute coronary syndrome (ACS). Platelet activation is central to the pathogenesis of NSTE-ACS and consensus guidelines that advocate early revascularization supported by intensive antiplatelet therapy. This review examines the drugs used concurrently with aspirin as dual antiplatelet therapy in the NSTE-ACS setting. Clopidogrel represented an important therapeutic advance. However, variations in platelet response and a relatively slow onset of action compromise outcomes with clopidogrel. Evidence reviewed in this article shows that in NSTE-ACS patients, ticagrelor and prasugrel are more effective than clopidogrel and are relatively well tolerated, with an acceptable and manageable bleeding risk. The literature suggests several differences between ticagrelor and prasugrel that should allow clinicians to better tailor treatment to the patient. Head-to-head comparisons are now needed to compare directly the risks and benefits of ticagrelor and prasugrel in NSTE-ACS. Further studies also need to address other outstanding issues such as the benefits and risks of prasugrel pre-treatment and to stratify efficacy and tolerability according to diabetes mellitus (DM) and other co-morbidities. In the meantime, the issues discussed in this review should enhance clinicians' ability to optimize and individualize NSTE-ACS treatment, thereby further reducing the morbidity and mortality associated with this common cardiovascular condition.

Does the urgency of endoscopic retrograde cholangiopancreatography (ercp)/percutaneous biliary drainage (pbd) impact mortality and disease related complications in ascending cholangitis? (deim-i study)

BACKGROUND

The Tokyo Guidelines have greatly impacted the management of ascending cholangitis. Though ERCP is the favored modality for biliary decompression, no evidence exists for the timing of ERCP. The DEIM-I study set out to determine if the time from patient presentation to biliary decompression impacted in hospital all cause mortality in ascending cholangitis.

METHOD

DEIM-I cohort study was a single-blinded and consisted of 250 subjects with moderate to severe ascending cholangitis who underwent ERCP/PBD. Subjects were randomized into quartiles based upon time from presentation until ERCP/PBD. The primary outcome utilized logistic regression to estimate relative risk (RR) of all cause, in hospital mortality with time to procedure as the predictive covariate. Secondary outcomes were analyzed using multivariate logistic regression and included; multiple organ failure (MOF), sepsis, systemic inflammatory response syndrome (SIRS), surgical incidence, hospital readmission and length of stay (LOS).

RESULTS

The risk for hospital mortality was significantly less when biliary drainage was performed within 11 h, compared to >42 h (RR 0.34, 95%CI 0.12 to 0.99, p=0.049). Hospital readmission was lower in subjects who underwent biliary decompression less than 11 h, when compared to those greater than 22 h. Subjects who underwent biliary decompression within 21 h had significant higher risk for surgery compared to those 22-42 h.

CONCLUSION

The relative risk of all cause in hospital mortality was lower in subjects who underwent biliary decompression in under 11 h compared to greater than 42 h.

The pharmacokinetics and pharmacodynamics of valsartan in the post-myocardial infarction population

INTRODUCTION

The most common risk factors for heart failure are hypertension and myocardial infarction. Angiotensin receptor blockers (ARBs) attenuate the deleterious effects of angiotensin II. Valsartan is a once or twice daily ARB that is FDA-approved for hypertension, LV dysfunction post-myocardial infarction and congestive heart failure as both an adjunct in ACE-inhibitor tolerant, and alternative in ACE-I intolerant patients.

AREAS COVERED

This article presents a comprehensive review of the literature regarding the pharmacokinetics and pharmacodynamics of valsartan, with particular attention paid to the post-myocardial infarction population.

EXPERT OPINION

Valsartan is a safe, well-tolerated and readily titratable ARB. In addition to its vasodilatory effects there are pleotropic effects associated with the ARB such as modulation of a number of neurohormonal regulators, cytokines and small molecules. Given the clear evidence-based benefits above and beyond its hypertensive properties, it has the potential, if priced appropriately, to grow in its impact as a pharmacotherapeutic long after its patent expires.

Appropriate anti-thrombotic/anti-thrombin therapy for thrombotic lesions

Managing coronary thrombus is a challenging task and requires adequate knowledge of the various antithrombotic agents available. In this article, we will briefly analyze the risk-benefit profile of antithrombotic agents, with critical analysis of the scientific evidence available to support their use. Since thrombus consists of platelets and coagulation cofactors, an effective antithrombotic strategy involves using one anticoagulant with two or more antiplatelet agents. Unfractionated heparin traditionally has been the most commonly used anticoagulant but is fast being replaced by relatively newer agents like LMWH, direct thrombin inhibitors, and Factor Xa inhibitors.

In recent years, the antiplatelet landscape has changed significantly with the availability of more potent and rapidly acting agents, like prasugrel and ticagrelor. These agents have demonstrated a sizeable reduction in ischemic outcomes in patients with ACS, who are treated invasively or otherwise, with some concern for an increased bleeding risk. Glycoprotein IIb/IIIa inhibitors have an established role in high risk NSTE ACS patients pretreated with dual antiplatelets, but its role in STEMI patients, treated with invasive approach and dual antiplatelets, has not been supported consistently across the studies. Additionally, in recent years, its place as a directly injected therapy into coronaries has been looked into with mixed results. In conclusion, a well-tailored antithrombotic strategy requires taking into account each patient’s individual risk factors and clinical presentation, with an effort to strike balance between not only preventing ischemic outcomes but also reducing bleeding complications.

Importance of potent P2Y(12) receptor blockade in acute myocardial infarction: focus on prasugrel

INTRODUCTION

Prasugrel therapy is recommended in patients with acute coronary syndromes (ACS) undergoing percutaneous coronary intervention (PCI).

AREAS COVERED

This article reviews the efficacy and safety profile of prasugrel, cost considerations, and its role in clinical practice based on published data. The authors searched PubMed and Ovid databases for English language clinical trial articles involving the use of prasugrel in human subjects and patients, published through June 2012. The keyword "prasugrel" was used. The review focuses on clinical trials, but other articles including Food and Drug Administration documents are also reviewed.

EXPERT OPINION

Prasugrel has a more rapid and greater pharmacodynamic (PD) effect than clopidogrel. No significant drug - drug interactions have been reported. In a large-scale randomized clinical trial, prasugrel was associated with better protection against ischemic event occurrence compared to clopidogrel, but more bleeding in ACS patients undergoing PCI. Adverse outcomes outweighed the benefit of prasugrel in certain subgroups, including patients over the age of 75, those weighing less than 60 kg, and patients with a prior history of stroke or transient ischemic attack. In subsequent PD studies, prasugrel therapy showed suboptimal platelet inhibition in selected patients. In addition, "hyper-responsiveness" to prasugrel may increase the risk of serious bleeding in high-risk patients. More detailed studies are warranted to explore antiplatelet regimens tailored to optimally limit ischemic and bleeding event occurrences. A Phase-III TRILOGY trial (NCT00699998) will indicate the clinical efficacy and safety of prasugrel in patients with non-ST-segment elevation ACS, who are medically managed without coronary revascularization.

Clopidogrel and interaction with proton pump inhibitors: comparison between cohort and within person study designs

OBJECTIVE

To measure the association between use of proton pump inhibitors and a range of harmful outcomes in patients using clopidogrel and aspirin.

DESIGN

Observational cohort study and self controlled case series.

SETTING

United Kingdom General Practice Research Database with linked data from the Myocardial Ischaemia National Audit Project (MINAP) and the Office for National Statistics (the cardiovascular disease research using linked bespoke studies and electronic records (CALIBER) collaboration)

POPULATION

24,471 patients receiving clopidogrel and aspirin.

MAIN OUTCOME MEASURES

The primary outcome was death or incident myocardial infarction. Secondary outcomes were death, incident myocardial infarction, vascular death, and non-vascular death. Comparisons were made between proton pump inhibitor use and non-use.

RESULTS

Of the 24,471 patients prescribed clopidogrel and aspirin, 12,439 (50%) were also prescribed a proton pump inhibitor at some time during the study. Death or incident myocardial infarction occurred in 1419 (11%) patients while they were receiving a proton pump inhibitor compared with 1341 (8%) who were not receiving a proton pump inhibitor. In multivariate analysis, the hazard ratio for the association between proton pump inhibitor use and death or incident myocardial infarction was 1.37 (95% confidence interval 1.27 to 1.48). Comparable results were seen for secondary outcomes and with other 2C19 inhibitors and with non-2C19 inhibitors. With the self controlled case series design to remove the effect of differences between people, there was no association between proton pump inhibitor use and myocardial infarction, with a rate ratio of 0.75 (0.55 to 1.01). Similarly, with the self controlled case series there was no association with myocardial infarction for other 2C19 inhibitors/non-inhibitors.

CONCLUSION

The lack of a specific association and the discrepancy between findings of the analyses between and within people suggests that the interaction between proton pump inhibitors and clopidogrel is clinically unimportant.

W, Thomas L, Alexander KP, Patel MR, Ohman EM, Gibler WB, Peterson ED, Roe MT. Polyvascular disease and long-term cardiovascular outcomes in older patients with non-ST-segment-elevation myocardial infarction

BACKGROUND

The impact of polyvascular disease (peripheral arterial disease [PAD] and cerebrovascular disease [CVD]) on long-term cardiovascular outcomes among older patients with acute myocardial infarction has not been well studied.

METHODS AND RESULTS

Patients with non-ST-segment-elevation myocardial infarction aged ≥65 years from the CRUSADE (Can Rapid Risk Stratification of Unstable Angina Patients Suppress Adverse Outcomes with Early Implementation of the ACC/AHA Guidelines) registry who survived to hospital discharge were linked to longitudinal data from the Centers for Medicare & Medicaid Services (n=34 205). All patients were presumed to have coronary artery disease (CAD) and were classified into the following 4 groups: 10.7% with prior CVD (CAD+CVD group); 11.5% with prior PAD (CAD+PAD); 3.1% with prior PAD and CVD (CAD+PAD+CVD); and 74.7% with no polyvascular disease (CAD alone). Cox proportional hazards modeling was used to examine the hazard of long-term mortality and composite of death or readmission for myocardial infarction or stroke (median follow-up, 35 months; interquartile range, 17-49 months). Compared with the CAD alone group, patients with polyvascular disease had greater comorbidities, were less likely to undergo revascularization, and received less often recommended discharge interventions. Three-year mortality rates increased with number of arterial bed involvement as follows: 33% for CAD alone, 49% for CAD+PAD, 52% for CAD+CVD, and 59% for CAD+PAD+CVD. Relative to the CAD alone group, patients with all 3 arterial beds involved had the highest risk of long-term mortality (adjusted hazard ratio [95% CI], 1.49 [1.38-1.61]; CAD+CVD, 1.38 [1.31-1.44]; CAD+PAD, 1.29 [1.23-1.35]). Similarly, the risk of long-term composite ischemic events was highest among patients in the CAD+PAD+CVD group.

CONCLUSIONS

Among older patients with non-ST-segment-elevation myocardial infarction, those with polyvascular disease have substantially higher long-term risk for recurrent events or death. Future studies targeting greater adherence to secondary prevention strategies and novel therapies are needed to help to reduce long-term cardiovascular events in this vulnerable population.

Bivalirudin versus unfractionated heparin in percutaneous coronary interventions of patients having received initial fondaparinux treatment: a propensity matched study

AIMS

Fondaparinux is an indirect, Factor Xa inhibitor that requires co-administration of another anticoagulant with anti-Factor IIa activity for percutaneous coronary intervention (PCI) per guideline recommendations. In this setting, the use of bivalirudin, a direct Factor IIa inhibitor, is not well established.

METHODS AND RESULTS

Using the Premier hospital database, we identified 971 patients who underwent elective or urgent PCI after receiving fondaparinux as the initial anticoagulant. They were treated with either bivalirudin ± glycoprotein IIb/IIIa inhibitor (GPI) (Group A=618) or unfractionated heparin (UFH) ± GPI (Group B=353) during PCI. A 2:1 propensity score matching (PSM) process was performed to control for patient and hospital level characteristics. The primary endpoints were to determine in-hospital death, bleeding and post-PCI length of stay (LOS) between treatment groups. After PSM, 512 matched patients were analysed (Group A=348 and Group B=174). In-hospital death was 1.4% in Group A vs. 2.9% in Group B (p=0.26). Clinically apparent bleeding occurred in 4.0% of Group A vs. 9.2% of Group B patients (p<0.02). Clinically apparent bleeding requiring transfusion was lower in Group A patients (0.6% vs. 2.9%; p=0.04). Post-PCI LOS was 1.9 ± 3.8 days for Group A and 2.4 ± 5.8 days for Group B (p=0.36). GPI use during PCI occurred in 9.2% of Group A vs. 44.8% of Group B patients (p<0.0001).

CONCLUSIONS

After initial administration of fondaparinux, a bivalirudin-based strategy for PCI is associated with significantly reduced bleeding, with similar mortality and post-PCI LOS when compared with an UFH-based strategy.

Management of non-ST-segment elevation acute coronary syndrome: comparison of the updated guidelines from North America and Europe

The American College of Cardiology/American Heart Association and the European Society of Cardiology published updated guidelines in 2011 for the management of patients with non-ST-segment elevation acute coronary syndrome. In this article, we highlight the most important new recommendations, review their supporting data, describe differences between the guidelines, and discuss new literature published since the latest guidelines were released. Key updates include detailed guidance regarding early risk stratification, use of coronary computed tomography angiography, selection of initial management strategy, novel antiplatelet agents, and new measures to enhance performance and quality. Major unique recommendations in the European Society of Cardiology guideline include endorsement of ticagrelor inhibitor or prasugrel (after delineation of coronary anatomy) as the first choice of P2Y12 inhibitors, establishment of protocols to identify patients for percutaneous coronary interventions vs. coronary artery bypass surgery, and use of the CRUSADE bleeding score. Meanwhile, unique recommendations in the American College of Cardiology/American Heart Association guideline include administration of prasugrel in selected patients before coronary angiography and consideration of continued dual antiplatelet therapy beyond 15 months after drug-eluting stent placement. Both guidelines include new recommendations endorsing platelet function and genetic testing in selected patients on clopidogrel, renal protection strategies, and less aggressive in patient's glycemic control. As these guidelines represent the most evidence-based approach, health care providers should become familiar with these updated recommendations to ensure optimal treatment of their patients with non-ST-segment elevation acute coronary syndrome.

Risk stratification and timing of revascularization: which patients benefit from early versus later revascularization?

In acute coronary syndromes, risk stratification is essential, particularly in patients without ST elevation, and is based upon clinical, electrocardiogram (ECG), and biological markers. Among them, recent and repeated attacks of angina, ST-segment deviation from baseline on the admission ECG as well as elevated markers of myonecrosis (particularly increased troponin levels), myocardial dysfunction (B-type natriuretic peptide [BNP]; N-terminal prohormone of BNP[NT-proBNP]), and inflammation (high-sensitivity C-reactive protein) are predictors of an adverse outcome. These variables can be incorporated into broader risk predictive scores, among which the TIMI (Thrombolysis in Myocardial Infarction) and GRACE (Global Registry of Acute Coronary Events) scores are the most widely used. Two general therapeutic strategies (routine invasive vs conservative or selective invasive) are employed in the treatment of non-ST-segment elevation acute coronary syndrome (NSTEACS). Evidence-based analysis and the current American College of Cardiology/American Heart Association/Society for Cardiac Angiography and Interventions clinical practice guidelines recommend an early invasive treatment strategy (8-24 h) for intermediate or high clinical risk patients with NSTEACS.

Clopidogrel and genetic testing: is it necessary for everyone?

Clopidogrel is a widely used antiplatelet agent to treat and prevent a variety of atherothrombotic diseases. More than a decade after its initial Food and Drug Administration approval, studies have emerged raising concerns regarding its possible reduced efficacy in patients who have impaired conversion of clopidogrel to its active metabolite (ie, poor metabolizers). Research has implicated genetic variations in the CYP2C19 isozyme as at least partly responsible for the variable antiplatelet response seen with clopidogrel. Studies have shown that patients possessing genetic variants of the CYP2C19 isozyme may be at increased risk of adverse cardiovascular events due to impaired clopidogrel efficacy, although this has not been definitively demonstrated. The Food and Drug Administration has issued a boxed warning regarding this concern. However, specific recommendations on genetic testing and alternative therapeutic strategies are not currently available. Genetic testing is commercially available to test patients for variability in the CYP2C19 isozyme, but altering antiplatelet therapy based on the results of this testing has not been adequately studied, and it is therefore not clear how to adjust therapy based on the results of this genetic testing. In addition, there are many other factors that may contribute to the variability in antiplatelet effect seen with clopidogrel besides CYP2C19 genetic polymorphisms. Ongoing trials dealing with adjusting antiplatelet therapy based on genetic testing will hopefully provide more useful information on how to appropriately integrate pharmacogenomics with the care of patients with atherothrombotic disease.

Interventional Management of ACS in Women: STEMI and NSTEMI

Acute coronary syndromes and ST elevation myocardial infarction are a major cause of cardiovascular morbidity and mortality in women. However, emerging data now suggest that the poorer outcomes of women undergoing percutaneous intervention may have less to do with differing vascular biology between males and females or the technical challenges of their coronary anatomy, but more with risk factors, such as age and comorbidities. Nevertheless, females have clearly been underrepresented in clinical trials, and further efforts are now required to properly define effective ways to tackle the risk-factor burden and clinical outcomes in women presenting to the catheterization laboratory.

A randomized controlled trial of stage-matched intervention for smoking cessation in cardiac out-patients

AIM

To examine the effectiveness of a stage-matched smoking cessation counselling intervention for smokers who had cardiac diseases.

METHODS

A total of 1860 Chinese cardiac patients who smoked at least one cigarette in the past 7 days and aged 18 years or above recruited from cardiac out-patient clinics in Hong Kong hospitals were allocated randomly to an intervention group or control group. The intervention group (n = 938) received counselling matched with their stage of readiness to quit by trained counsellors at baseline, 1 week and 1 month. The control group (n = 922) received brief counselling on healthy diet at baseline. The primary outcomes were self-reported 7-day and 30-day point prevalence (PP) of tobacco abstinence at 12 months after baseline. The secondary outcome measures included biochemically validated abstinence at 12-month follow-up, self-reported 7-day and 30-day PP abstinence and reduction of cigarette consumption by 50% at 3 and 6 months.

RESULTS

By intention-to-treat analysis, the intervention and control groups showed no significant difference in self-reported 7-day PP abstinence (intervention: 26.5% versus control: 25.5%; P = 0.60) and 30-day PP (intervention: 25.4% versus control: 24.2%; P = 0.55), biochemically validated abstinence (intervention: 6.6% versus control: 4.9%; P = 0.14) and overall quit attempts of least 24 hours (intervention: 40.3% versus control: 34.3%; P = 0.007) at the 12-month follow-up, adjusted for the baseline stage of readiness to quit smoking.

CONCLUSIONS

An intervention, based on the Stages of Change model, to promote smoking cessation in cardiac patients in China failed to find any long-term benefit.

Future Perspectives on Percutaneous Coronary Interventions in Women

In the United States alone, more than 1 million cardiac catheterizations are performed each year, with approximately 600,000 patients undergoing percutaneous coronary intervention (PCI). A meaningful perspective on the future of PCI in women requires not only reflection on some of the major developments in interventional cardiology but also a look back more generally at the changing patterns in the burden of coronary disease in the population and at the gains accrued in understanding and combating cardiovascular disease in women.

Admission International Normalized Ratio Levels, Early Treatment Strategies, and Major Bleeding Risk Among Non–ST-Segment–Elevation Myocardial Infarction Patients on Home Warfarin Therapy

Background—

Non–ST-segment–elevation myocardial infarction patients on home warfarin pose treatment concerns because of their potential increased risk of bleeding. Expert opinion from the American College of Cardiology/American Heart Association guidelines suggest holding anticoagulants and initiating antiplatelet therapy among therapeutically anticoagulated non–ST-segment–elevation myocardial infarction patients. Yet, little is known about contemporary treatment patterns and bleeding risks in this population.

Methods and Results—

We stratified 5787 non–ST-segment–elevation myocardial infarction patients on home warfarin therapy using data from the National Cardiovascular Data Registry Acute Coronary Treatment and Intervention Outcomes Network Registry–Get With the Guidelines by admission international normalized ratio (INR) levels: subtherapeutic (INR <2), therapeutic (INR, 2–3), and supratherapeutic (INR >3). Multivariable logistic generalized estimating equations models were constructed to examine the associations between admission INR level, early antithrombotic treatment and invasive therapy, and risk of in-hospital major bleeding. Among these patients, 46%, 35%, and 19% had subtherapeutic, therapeutic, and supratherapeutic admission INR levels, respectively. Risk of major bleeding was higher among patients with therapeutic (15%; adjusted odds ratio, 1.25; 95% confidence interval [CI], 1.03–1.50) and supratherapeutic (22%; odds ratio, 1.60; 95% CI, 1.30–1.97) anticoagulation compared with the subtherapeutic group (12%). Among patients with admission INR ≥2, 45% were treated with early (within 24 hours) heparin, 35% with early clopidogrel, 14% with early glycoprotein IIb/IIIa inhibitor, and 36% with early invasive strategy. Early antithrombotic treatment was associated with increased bleeding risk (odds ratio, 1.40 [95% CI, 1.14–1.72] for heparin; 1.50 [95% CI, 1.22–1.84] for clopidogrel; and 1.82 [95% CI, 1.43–2.32] for glycoprotein IIb/IIIa inhibitor); however, an early invasive strategy was not (odds ratio, 1.09; 95% CI, 0.86–1.37). No significant interactions were observed between INR level and use of each early treatment in its association with bleeding.

Conclusions—

National patterns of early antithrombotic treatment for non–ST-segment–elevation myocardial infarction patients on home warfarin diverge from expert opinion provided by current practice guidelines. Early antithrombotic treatment was associated with increased bleeding risk regardless of admission INR level.

Stent thrombosis: incidence, predictors and new technologies

Some concerns have been raised regarding the risk of late and very late stent thrombosis (ST) following drug-eluting stent implantation. Despite remaining an uncommon complication of percutaneous coronary intervention, when ST occurs, it can be catastrophic to the individual, commonly presenting as acute ST elevation myocardial infarction or sudden cardiac death. The incidence and predictors of ST have been reported in the literature and the role of dual antiplatelet therapies in the avoidance of such a complication remains vital. Ongoing studies are assessing the role of these therapies including platelet reactivity testing, genetic testing and optimum duration of therapy. In addition, newer polymer-free and bioabsorbable stents are under investigation in the quest to potentially minimise the risk of ST.

Platelet function measurement-based strategy to reduce bleeding and waiting time in clopidogrel-treated patients undergoing coronary artery bypass graft surgery: the timing based on platelet function strategy to reduce clopidogrel-associated bleeding related to CABG (TARGET-CABG) study

BACKGROUND

Aspirin and clopidogrel therapy is associated with a variable bleeding risk in patients undergoing coronary artery bypass graft surgery (CABG). We evaluated the role of platelet function testing in clopidogrel-treated patients undergoing CABG.

METHODS AND RESULTS

One hundred eighty patients on background aspirin with/without clopidogrel therapy undergoing elective first time isolated on-pump CABG were enrolled in a prospective single-center, nonrandomized, unblinded investigation (Timing Based on Platelet Function Strategy to Reduce Clopidogrel-Associated Bleeding Related to CABG [TARGET-CABG] study) between September 2008 and January 2011. Clopidogrel responsiveness (ADP-induced platelet-fibrin clot strength [MA(ADP)]) was determined by thrombelastography; CABG was done within 1 day, 3-5 days, and >5 days in patients with an MA(ADP) >50 mm, 35-50 mm, and <35 mm, respectively. The primary end point was 24-hour chest tube drainage and key secondary end point was total number of transfused red blood cells. Equivalence was defined as ≤25% difference between groups. ANCOVA was used to adjust for confounders. Mean 24-hour chest tube drainage in clopidogrel-treated patients was 93% (95% confidence interval, 81-107%) of the amount observed in clopidogrel-naive patients, and the total amount of red blood cells transfused did not differ between groups (1.80 U versus 2.08 U, respectively, P=0.540). The total waiting period in clopidogrel-treated patients was 233 days (mean, 2.7 days per patient).

CONCLUSIONS

A strategy based on preoperative platelet function testing to determine the timing of CABG in clopidogrel-treated patients was associated with the same amount of bleeding observed in clopidogrel-naive patients and ≈50% shorter waiting time than recommended in the current guidelines.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00857155.

Evolving role of platelet function testing in coronary artery interventions

The substantial reduction in ischemic events provided by the dual antiplatelet regimen with aspirin and clopidogrel is well documented in patients with acute coronary syndrome and patients undergoing percutaneous coronary intervention. Recently the variable response to the antiplatelet agents has received considerable attention after several “boxed warnings” on clopidogrel. This led to intense controversy on pharmacokinetic, pharmacodynamic, and pharmacogenomic issues of antiplatelet drugs, especially clopidogrel. Research use of platelet function testing has been successfully validated in identifying new antiplatelet drugs like prasugrel and ticagrelor. These platelet function assays are no longer regarded just as a laboratory phenomenon but rather as tools that have been shown to predict mortality in several clinical trials. It is believed that suboptimal response to an antiplatelet regimen (pharmacodynamic effect) may be associated with cardiovascular, cerebrovascular, and peripheral arterial events. There has been intense controversy about this variable response of antiplatelet drugs and the role of platelet function testing to guide antiplatelet therapy. While the importance of routine platelet function testing may be uncertain, it may be useful in high-risk patients such as those with diabetes mellitus, diffuse three vessels coronary artery disease, left main stenosis, diffuse atherosclerotic disease, and those with chronic renal failure undergoing percutaneous coronary intervention. It could also be useful in patients with suspected pharmacodynamic interaction with other drugs to assure the adequacy of platelet inhibition. While we wait for definitive trials, a predictive prognostic algorithm is necessary to individualize antiplatelet therapy with P2Y12 inhibitors based on platelet function assays and genetic testing.

ABCB1 C3435T polymorphism and risk of adverse clinical events in clopidogrel treated patients: a meta-analysis

INTRODUCTION

The ABCB1 C3435T polymorphism limits oral bioavailability of clopidogrel and may influence prognosis of patients treated with clopidogrel. Several studies have examined the association between the C3435T polymorphism and risk of adverse clinical events in clopidogrel treated patients, but the results were inconsistent. To assess the role of the C3435T polymorphism in the impact on clinical outcomes, a meta-analysis was conducted.

METHODS

6 studies with 10,153 subjects were included in this meta-analysis. Fixed- or random-effects model was chosen according to heterogeneity. Publication bias was evaluated by fail-safe numbers.

RESULTS

The association of the C3435T polymorphism with risk of overall recurrent ischemic events in clopidogrel treated patients was not statistically significant for all genetic models (OR=1.13, 95%CI: 0.78-1.64, P=0.51; OR=1.15, 95%CI: 0.99-1.33, P=0.07; OR=1.19, 95%CI: 0.81-1.76, P=0.37). Significant association was identified between the C3435T polymorphism and risk of short-term recurrent ischemic events (OR=1.55, 95% CI: 1.09-2.20, P=0.01; OR=1.41, 95% CI: 1.06-1.87, P=0.02; OR=1.77, 95% CI: 1.19-2.63, P=0.005). No statistically significant association between the C3435T polymorphism and stent thrombosis (OR=0.79, 95% CI: 0.47-1.32, P=0.37) or bleeding (OR=0.98, 95% CI: 0.79-1.21, P=0.82) was identified. The results may be affected by publication bias.

CONCLUSIONS

This meta-analysis failed to show an association between the ABCB1 C3435T polymorphism and risk of overall recurrent ischemic events, stent thrombosis or bleeding in clopidogrel treated patients. However, the association between TT homozygotes of the C3435T polymorphism and risk of short-term recurrent ischemic events may exist, but needs more studies to confirm.

Incidence of bleeding in renally impaired patients receiving incorrectly dosed eptifibatide or bivalirudin while undergoing percutaneous coronary intervention

BACKGROUND

Limited data are available regarding adverse bleeding events associated with antithrombotic agents incorrectly dosed based on renal function in patients receiving percutaneous coronary intervention (PCI).

OBJECTIVE

To compare the incidence of bleeding during their hospital stay in patients with reduced renal function receiving incorrect doses of bivalirudin or eptifibatide to the incidence of correct doses, based on manufacturer recommendations; secondary objectives were to determine the incidence of correct dosing based on manufacturer recommendations and the incidence of TIMI (Thrombolysis in Myocardial Infarction) major bleeding.

METHODS

A chart review over a 32-month period showed that patients with reduced renal function who received either eptifibatide or bivalirudin during PCI were evaluated for correct dosing based on manufacturer recommendations, bleeding incidence according to the TIMI criteria, and extent of bleeding according to the TIMI and GUSTO (Global Use of Strategies to Open Occluded Coronary Arteries) criteria.

RESULTS

One hundred ninety patients met inclusion criteria, 56 who received eptifibatide and 134 who received bivalirudin. Eptifibatide was dosed incorrectly in 64% of the patients. Patients receiving incorrectly dosed compared to correctly dosed eptifibatide experienced significantly more bleeding (64% vs 35%, respectively, p = 0.04), a greater extent of bleeding based on the TIMI and GUSTO criteria (p = 0.03 and p = 0.009, respectively), and had more TIMI major bleeding (19% vs 5%, respectively). Bivalirudin was dosed incorrectly in 28% of the patients. Patients receiving incorrectly dosed compared to correctly dosed bivalirudin experienced a significantly greater extent of bleeding based on the GUSTO criteria (p = 0.01). There was no significant difference between the incidence of bleeding (37% vs 21%, respectively; p = 0.06), extent of bleeding based on the TIMI criteria (p = 0.058), or incidence of TIMI major bleeding (5% vs 3%).

CONCLUSIONS

Patients receiving incorrectly dosed eptifibatide and bivalirudin are susceptible to adverse bleeding events. The occurrence of incorrect dosing offers an opportunity for pharmacist-driven institutional improvement.

2011 ACCF/AHA focused update of the guidelines for the management of patients with Unstable Angina/Non-ST-Elevation Myocardial Infarction (updating the 2007 Guideline): highlights for the clinician

The 2011 Update to the Unstable Angina/Non-ST-Elevation Myocardial Infarction (UA/NSTEMI) Guideline is based in evolving data or expert opinion and incorporates information from late-breaking clinical trials presented at the 2008-2009 Scientific Sessions of the American College of Cardiology, the American Heart Association, and the European Society of Cardiology, among others, as well as selected data through April 2010. The 5 key issues highlighted in this summary are: (1) the timing of acute interventional therapy in non-ST-elevation myocardial infarction; (2) emphasis on the timing, duration, and application of dual and triple antiplatelet therapy; (3) specific recommendations for patients with diabetes mellitus; (4) the role and potential benefit of invasive therapy in patients with advanced renal dysfunction; and (5) issues of quality improvement for acute coronary syndromes.

Critical appraisal of ticagrelor in the management of acute coronary syndrome

Ticagrelor is a novel P2Y₁₂ receptor antagonist which, like clopidogrel and prasugrel, functions by blocking adenosine diphosphate-mediated platelet aggregation. However, unlike the aforementioned agents, the binding of ticagrelor to this receptor is reversible. Ticagrelor is also believed to mediate some of its beneficial effects by augmenting the effects of adenosine, which is another unique pharmacologic property of this drug. In terms of antiplatelet effect, ticagrelor is more potent than clopidogrel and produces a faster and stronger inhibition of platelet aggregation. This may also be an advantage of ticagrelor over prasugrel, but this has not been adequately studied. Due to the reversible nature of the binding of ticagrelor to the platelet receptor, ticagrelor has a relatively fast offset of effect, with platelet aggregation approaching pretreatment levels about 3 days after discontinuation of therapy. This has advantages in patients requiring invasive procedures, but also makes medication adherence very important in order to be able to maintain an effective antiplatelet effect. Ticagrelor has been shown to be clinically superior to clopidogrel when given to patients with an acute coronary syndrome, resulting in significantly lower rates of myocardial infarction and vascular death. However, ticagrelor is indicated to be administered with aspirin, and the clinical benefits of ticagrelor may be less when daily dosages of aspirin exceed 100 mg. As expected, bleeding is the most common adverse effect with ticagrelor, although it occurs at rates comparable with those seen for clopidogrel with the exception of noncoronary artery bypass graft-related major bleeding and fatal intracranial bleeds, the latter of which occurs only rarely. Dyspnea is another common adverse effect with ticagrelor, although this is usually not severe and resolves with drug discontinuation. Unlike clopidogrel, there are no known pharmacogenomic concerns with ticagrelor, and emerging data suggest ticagrelor to be effective in patients resistant to clopidogrel, although more study is needed on this topic. While preliminary data suggest ticagrelor to be cost effective when compared with generic clopidogrel, the acquisition cost of ticagrelor is not insignificant and this will likely be an issue for many health care organizations. Currently, ticagrelor is well positioned to assume an active role in the treatment of coronary artery disease due to an impressive efficacy profile and reasonable safety. Its ultimate role in therapy will continue to evolve as studies on this drug continue eg, (Prevention of Cardiovascular Events in Patients with Prior Heart Attack Using Ticagrelor Compared to Placebo on a Background of Aspirin, PEGASUS) and more information hopefully becomes available on its use in clopidogrel nonresponders and relative safety and efficacy compared with prasugrel.

Rethinking cocaine-associated chest pain and acute coronary syndromes

Every year more than 500,000 patients present to the emergency department with cocaine-associated complications, most commonly chest pain. Many of these patients undergo extensive work-up and treatment. Much of the evidence regarding cocaine's cardiovascular effects, as well as the current management of cocaine-associated chest pain and acute coronary syndromes, is anecdotally derived and based on studies written more than 2 decades ago that involved only a few patients. Newer studies have brought into question many of the commonly held theories and practices regarding the etiology, diagnosis, and treatment of this common clinical scenario. However, there continues to be a paucity of prospective, randomized trials addressing this topic as it relates to clinical outcomes. We searched PubMed for English-language articles from 1960 to 2011 using the keywords cocaine, chest pain, coronary arteries, myocardial infarction, emergency department, cardiac biomarkers, electrocardiogram, coronary computed tomography, observation unit, β-blockers, benzodiazepines, nitroglycerin, calcium channel blockers, phentolamine, and cardiomyopathy; including various combinations of these terms. We reviewed the abstracts to confirm relevance, and then full articles were extracted. References from extracted articles were also reviewed for relevant articles. In this review, we critically evaluate the limited historical evidence underlying the current teachings on cocaine's cardiovascular effects and management of cocaine-associated chest pain. We aim to update the reader on more recent, albeit small, studies on the emergency department evaluation and clinical and pharmacologic management of cocaine-associated chest pain. Finally, we summarize recent guidelines and review an algorithm based on the current best evidence.

Treatment with adenosine diphosphate receptor inhibitors-longitudinal assessment of treatment patterns and events after acute coronary syndrome (TRANSLATE-ACS) study design: expanding the paradigm of longitudinal observational research

BACKGROUND

Platelet inhibition is critical in reducing both short- and long-term atherothrombotic risks after acute myocardial infarction (MI), especially among patients managed with percutaneous coronary intervention (PCI). Currently available antiplatelet medications, including adenosine diphosphate (ADP) receptor inhibitors, have demonstrated variability in efficacy and safety in clinical trials, yet few studies have examined contemporary "real-world" approaches to platelet inhibition and associated outcomes.

METHODS

TRANSLATE-ACS is a prospective observational study that will track up to 17,000 MI patients managed with PCI, from the inhospital to outpatient settings for up to 12 months postdischarge to provide a comprehensive picture of current treatment patterns and outcomes in routine clinical practice. TRANSLATE-ACS exemplifies a collaborative study design that efficiently builds upon a well-established PCI registry platform, and yet, through a systematic telephone interview follow-up process, provides important longitudinal clinical and economic follow-up capacity through 15 months after initial MI hospitalization. Furthermore, TRANSLATE-ACS incorporates a hospital-level, clustered, randomized substudy to investigate the impact of point-of-care platelet inhibition testing on subsequent patient management. Finally, TRANSLATE-ACS provides feedback through quarterly reports to participating sites on their care practices benchmarked to peer performance to support and promote longitudinal quality of cardiovascular care delivery.

CONCLUSION

TRANSLATE-ACS not only addresses important clinical and scientific questions but also includes pioneering design features that will assist in the evolution of clinical registries.