2015 ESC Guidelines for the management of acute coronary syndromes in patients presenting without persistent ST-segment elevation

Identification of High-Risk Patients with Non-ST Segment Elevation Myocardial Infarction using Strain Doppler Echocardiography: Correlation with Cardiac Magnetic Resonance Imaging

Assessment of left ventricular (LV) function is important for decision-making and risk stratification in patients with acute coronary syndrome. Many patients with non-ST segment elevation myocardial infarction (NSTEMI) have substantial infarction, but these patients often do not reveal clinical signs of instability, and they rarely fulfill criteria for acute revascularization therapy.

AIM

This study evaluated the potential of strain Doppler echocardiography analysis for the assessment of LV infarct size when compared with standard two-dimensional echo and cardiac magnetic resonance (CMR) data.

METHODS

Thirty patients with NSTEMI were examined using echocardiography after hospitalization for 1.8 ± 1.1 days for the assessment of left ventricular ejection fraction, wall motion score index (WMSI), and LV global longitudinal strain (GLS). Infarct size was assessed using delayed enhancement CMR 6.97 ± 3.2 days after admission as a percentage of total myocardial volume.

RESULTS

GLS was performed in 30 patients, and 82.9% of the LV segments were accepted for GLS analysis. Comparisons between patients with a complete set of GLS and standard echo, GLS and CMR were performed. The linear relationship demonstrated moderately strong and significant associations between GLS and ejection fraction (EF) as determined using standard echo (r = 0.452, P = 0.012), WMSI (r = 0.462, P = 0.010), and the gold standard CMR-determined EF (r = 0.57, P < 0.001). Receiver operating characteristic curves were used to analyze the ability of GLS to evaluate infarct size. GLS was the best predictor of infarct size in a multivariate linear regression analysis (β = 1.51, P = 0.027). WMSI >1.125 and a GLS cutoff value of -11.29% identified patients with substantial infarction (≥12% of total myocardial volume measured using CMR) with accuracies of 76.7% and 80%, respectively. However, GLS remained the only independent predictor in a multivariate logistic regression analysis to identify an infarct size ≥12%.

CONCLUSION

GLS is a good predictor of infarct size in NSTEMI, and it may serve as a tool in conjunction with risk stratification scores for the selection of high-risk NSTEMI patients.

Waist-hip ratio and 1-year clinical outcome in patients with non-ST-elevation myocardial infarctions

OBJECTIVES

Obesity is a well-known cardiovascular disease risk factor. We evaluated the relationship between the waist-hip ratio (WHR), as a surrogate marker of central obesity, and clinical outcomes in patients with non-ST-segment elevation myocardial infarctions (NSTEMIs) undergoing percutaneous coronary interventions (PCIs).

METHODS

Between 2008 and 2010, NSTEMI patients who underwent PCI and who had available anthropometric data were divided into three groups according to their WHR tertile range. Clinical outcomes in the groups were analyzed.

RESULTS

Increasing incidences of hypertension and diabetes mellitus were associated with increasing WHR. As the WHR increased, a disintegration of patient metabolic patterns was documented in laboratory findings. There was no difference in the 1-year mortality rates between the three groups. However, increasing 1-year major adverse cardiovascular event rates were documented as the WHR increased (13, 14.7, and 19.4% in tertile groups 1-3, respectively; P=0.005). After adjusting for confounding variables, the highest tertile group was associated with increased 1-year mortality and major adverse cardiovascular event rates compared with the lowest tertile group. These differences arose from the female subgroup, suggesting that the magnitude of the central obesity effect might be greater in female than in male patients.

CONCLUSION

Central obesity, represented by WHR, was associated with poor clinical outcomes in NSTEMI patients undergoing PCI, particularly among women.

Excess mortality and guideline-indicated care following non-ST-elevation myocardial infarction

BACKGROUND

Adherence to guideline-indicated care for the treatment of non-ST-elevation myocardial infarction (NSTEMI) is associated with improved outcomes. We investigated the extent and consequences of non-adherence to guideline-indicated care across a national health system.

METHODS

A cohort study ( ClinicalTrials.gov identifier: NCT02436187) was conducted using data from the Myocardial Ischaemia National Audit Project ( n = 389,057 NSTEMI, n = 247 hospitals, England and Wales, 2003-2013). Accelerated failure time models were used to quantify the impact of non-adherence on survival according to dates of guideline publication.

RESULTS

Over a period of 1,079,044 person-years (median 2.2 years of follow-up), 113,586 (29.2%) NSTEMI patients died. Of those eligible to receive care, 337,881 (86.9%) did not receive one or more guideline-indicated intervention; the most frequently missed were dietary advice ( n = 254,869, 68.1%), smoking cessation advice ( n = 245,357, 87.9%), P2Y12 inhibitors ( n = 192,906, 66.3%) and coronary angiography ( n = 161,853, 43.4%). Missed interventions with the strongest impact on reduced survival were coronary angiography (time ratio: 0.18, 95% confidence interval (CI): 0.17-0.18), cardiac rehabilitation (time ratio: 0.49, 95% CI: 0.48-0.50), smoking cessation advice (time ratio: 0.53, 95% CI: 0.51-0.57) and statins (time ratio: 0.56, 95% CI: 0.55-0.58). If all eligible patients in the study had received optimal care at the time of guideline publication, then 32,765 (28.9%) deaths (95% CI: 30,531-33,509) may have been prevented.

CONCLUSION

The majority of patients hospitalised with NSTEMI missed at least one guideline-indicated intervention for which they were eligible. This was significantly associated with excess mortality. Greater attention to the provision of guideline-indicated care for the management of NSTEMI will reduce premature cardiovascular deaths.

Platelet reactivity in patients receiving a maintenance dose of P2Y12-ADP receptor antagonists undergoing elective percutaneous coronary intervention

BACKGROUND

P2Y12-ADP receptor blockade during percutaneous coronary intervention (PCI) is critical to prevent thrombotic events. In patients under chronic P2Y12 blockers, the use of additional loading dose (LD) before an elective PCI is debated. We aimed to investigate the rate of high on-treatment platelet reactivity (HTPR) in patients undergoing elective PCI during chronic clopidogrel or ticagrelor therapy.

METHODS AND RESULTS

We performed a sub-group analysis of a randomized trial comparing ticagrelor and clopidogrel in acute coronary syndrome (ACS) patients undergoing PCI. Multi-vessel disease patients requiring a staged PCI one month after the ACS were included. The VASP (vasodilatatory phosphoprotein) index, which is a specific and reproducible platelet assay to measure P2Y12-ADP receptor activity, was used to assess the biological efficacy of the maintenance dose (MD) of ticagrelor and clopidogrel before PCI. Forty-one patients in each group of randomization required a staged PCI. They were similar regarding the baseline demographic, clinical and angiographic characteristics. The mean VASP index in the ticagrelor group was 20.7±8.8% compared to 51.8±17% in the clopidogrel group (p<0.001) before PCI. No patients had a VASP index ≥50% in the ticagrelor group compared to 56% in the clopidogrel group (p<0.001). Following PCI the rate of peri-procedural MI was higher in the clopidogrel group (p=0.02).

CONCLUSIONS

Unlike clopidogrel MD, ticagrelor MD achieves an optimal PR inhibition in all patients during a staged PCI.

Dual Antiplatelet Therapy After Drug-eluting Stent Implantation

The current guidelines for percutaneous coronary intervention use recommend dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 inhibitor after drug eluting stent (DES) implantation. The optimal duration of DAPT is however area of debate. Recent clinical trials and meta-analyses suggest that the choice of DAPT duration should be tailored individually, based on the balance between ischemic and bleeding risk carried by the patient.

Gaining a New Skill With the Risk of Losing One: The Effect of Radial Catheterization

The adoption of radial catheterization has been relatively slow in the United States. This study was conducted to assess the perceived comfort level of cardiology fellows with radial catheterizations and to predict the practice patterns in the United States in the near future. A 21-question survey on cardiology fellows' preferred cardiac catheterization access site was conducted between April and June 2015. Data on access preference and perceived competency were analyzed based on the fellow's level of training and type of training program (university vs community). A total of 101 responses were received from a total of 250 invitations; 85 (85%) of these respondents completed all questions. Data were collected from fellows of several programs nationwide. Of the 85 respondents with complete data, 22%, 29%, and 19% were first-, second-, and third-year interventional fellows respectively. Most respondents (82%) were from university-based programs, 46.3% of respondents considered that their programs provided a balance of both radial and femoral training. Irrespective of the training year, most fellows seemed to prefer radial over femoral access. Senior fellows appeared to be equally comfortable with a femoral access approach (P = 0.03). There was no difference by training site (university vs community programs) (P = 0.921). In 2015, US cardiology fellows appear to prefer radial over femoral access for cardiac catheterizations. Although it is good to see the shift toward better radial access skills, we need to stress the importance of the femoral skills that would be necessary to keep in the armamentarium of interventional cardiologists.

Roles of High-Density Lipoprotein Cholesterol in Patients With Acute Myocardial Infarction

Many observational studies showed hogh-density lipoprotein cholesterol (HDL-C) is a strong inverse predictor of cardiovascular (CV) outcome. However, recent large clinical trials evaluating therapies to raise HDL-C level in those already on statin therapy have been discouraging. This complexity is not well-known.A total of 28,357 acute myocardial infarction (AMI) patients were enrolled in the Korea Acute Myocardial Infarction Registry (KAMIR), which was a prospective, multicenter, nationwide, web-based database of AMI in Korea. From this registry, we evaluated 3574 patients with AMI who have follow-up HDL-C level to investigate its association with clinical outcomes. The primary endpoint was the relationship between follow-up change in HDL-C and a 12-month composite of major adverse cardiac events (MACEs).Patients with initial HDL-C ≥ 40 mg/dL showed significantly lower rates of 12-month MACEs, especially cardiac and all-cause mortalities (P < 0.001). When patients were stratified into 4 groups according to the change of HDL-C, patients with decreasing HDL-C showed significantly higher rates of 12-month MACEs as comparable with patients with increasing HLD-C. A multivariate analysis indicated that HDL-C level was a significant predictor of CV events (hazard ratio, 1.38; 95% confidence interval, 1.12-1.71) after correcting for confounding variables.The follow-up change in HDL-C level was significantly related with CV outcomes in patients with AMI.

Trends in P2Y12 Inhibitor Use in Patients Referred for Invasive Evaluation of Coronary Artery Disease in Contemporary US Practice

Practice in patients undergoing invasive evaluation for coronary artery disease is variable regarding choice of P2Y12 inhibitor and timing of treatment initiation and is usually dictated by institutional or even individual operator preference. Limited data are available on the actual patterns of P2Y12 inhibitor use in contemporary practice in the United States. We used electronic medical records from the Cerner "Health Facts" database of adults who underwent coronary angiography with or without percutaneous coronary intervention (PCI) from January 2008 to June 2013 and who received a loading dose of clopidogrel, prasugrel, or ticagrelor at any time from 48 hours before the start of procedure up to 6 hours after. Timing of P2Y12 inhibitor administration was categorized as >2 hours before, 0 to 2 hours before (pretreatment groups), or after the start of procedure. Results were also evaluated according to type of P2Y12 inhibitor and patient clinical presentation. A total of 37,964 patients underwent coronary angiography, and 28,306 proceeded to PCI. Pretreatment with a P2Y12 inhibitor was observed in 28% and 23% in the overall and PCI populations, respectively. Moderate variability of pretreatment rates was noted relative to clinical presentation and P2Y12 inhibitor type. Pretreatment rates remained fairly constant over time with the exception of a decreasing trend with prasugrel. In conclusion, among patients referred for invasive evaluation of coronary artery disease, P2Y12 inhibitor pretreatment was low in contemporary US practice, an observation consistent over time and for all available agents and clinical presentations.

Platelet-Mediated Thrombosis

The pivotal role that platelets play in thrombosis and resultant ischemic event occurrences in patients with high-risk coronary artery disease is well established. This role provides the fundamental basis for the current wide implementation of dual antiplatelet therapy with aspirin and a P2Y 12 receptor inhibitor. The development of user friendly point-of-care methods to assess platelet reactivity to adenosine diphosphate has increased the frequency of platelet function testing in clinical practice. Recent large observational studies have established an independent relation between the results of point-of-care platelet function testing and clinical event occurrence in patients undergoing coronary artery stenting. However, prospective, randomized trials have failed to demonstrate that personalized antiplatelet therapy based on point-of-care assessment of platelet function is effective in reducing ischemic event occurrences. Important limitations were associated with these trials. In addition, the concept of a therapeutic window of P2Y 12 receptor reactivity with an upper threshold associated with ischemic event occurrence and a lower threshold associated with bleeding has also been proposed. In the absence of strong prospective evidence to support personalized antiplatelet therapy, clinical decision making about antiplatelet therapy rests on the large body of observational data and the fundamental importance of platelet physiology in catastrophic event occurrence in patients with high-risk coronary artery disease.

Different Prognostic Significance of Cardiac Troponin at Presentation and Peak Cardiac Troponin in Patients with Non-ST Segment Elevation Myocardial Infarction

OBJECTIVES

Non-ST elevation myocardial infarction (NSTEMI) is one of the most common manifestations of acute coronary syndromes (ACS). We evaluated the prognostic role of cardiac troponin I (cTnI) at presentation and peak cardiac troponin I in patients with NSTEMI.

METHODS

We consecutively enrolled 215 subjects presenting with NSTEMI. Subjects were followed up for 1 year. cTnI at presentation and the peak value of cTnI were measured. The primary end point was defined as cardiovascular death, readmission to hospital with heart failure and new ACS.

RESULTS

The subjects who presented the primary end point (49 subjects) had significantly increased values of peak cTnI compared to subjects free of cardiovascular events [7.19 (2.97-21.32) vs. 4.09 (1.18-11.85) ng/l; p = 0.002]. Nevertheless, cTnI at presentation did not differ between subjects who presented the primary end point and those free of events (p = 0.39). Multivariate Cox regression analysis after adjustment for confounders revealed by the univariate analysis showed that for an increase in peak cTnI from 1 to 10 ng/l, there is a 60% anticipated increase in the relative risk to present the primary end point (p = 0.04).

CONCLUSION

These findings documented the different prognostic significance of cTnI at presentation and peak cTnI in patients presenting with NSTEMI, and highlighted the importance of monitoring the levels of cTnI in this high-risk population.

Canada acute coronary syndrome score was a stronger baseline predictor than age ≥75 years of in-hospital mortality in acute coronary syndrome patients in western Romania

BACKGROUND

Several risk scores were developed for acute coronary syndrome (ACS) patients, but their use is limited by their complexity.

PURPOSE

The purpose of this study was to identify predictors at admission for in-hospital mortality in ACS patients in western Romania, using a simple risk-assessment tool - the new Canada acute coronary syndrome (C-ACS) risk score.

PATIENTS AND METHODS

The baseline risk of patients admitted with ACS was retrospectively assessed using the C-ACS risk score. The score ranged from 0 to 4; 1 point was assigned for the presence of each of the following parameters: age ≥75 years, Killip class >1, systolic blood pressure <100 mmHg, and heart rate >100 bpm.

RESULTS

A total of 960 patients with ACS were included, 409 (43%) with ST-segment elevation myocardial infarction (STEMI) and 551 (57%) with non-ST-segment elevation acute coronary syndrome (NSTE-ACS). The C-ACS score predicted in-hospital mortality in all ACS patients with a C-statistic of 0.95 (95% CI: 0.93-0.96), in STEMI patients with a C-statistic of 0.92 (95% confidence interval [CI]: 0.89-0.94), and in NSTE-ACS patients with a C-statistic of 0.97 (95% CI: 0.95-0.98). Of the 960 patients, 218 (22.7%) were aged ≥75 years. The proportion of patients aged ≥75 years was 21.7% in the STEMI subgroup and 23.4% in the NSTE-ACS subgroup (P>0.05). Age ≥75 years was significantly associated with in-hospital mortality in ACS patients (odds ratio [OR]: 3.25, 95% CI: 1.24-8.25) and in the STEMI subgroup (OR >3.99, 95% CI: 1.28-12.44). Female sex was strongly associated with mortality in the NSTE-ACS subgroup (OR: 27.72, 95% CI: 1.83-39.99).

CONCLUSION

We conclude that C-ACS score was the strongest predictor of in-hospital mortality in all ACS patients while age ≥75 years predicted the mortality well in the STEMI subgroup.

Impact of concomitant use of proton pump inhibitors and clopidogrel or ticagrelor on clinical outcomes in patients with acute coronary syndrome

Background

There is great debate on the possible adverse interaction between proton pump inhibitors (PPIs) and clopidogrel. In addition, whether the use of PPIs affects the clinical efficacy of ticagrelor remains less known. We aimed to determine the impact of concomitant administration of PPIs and clopidogrel or ticagrelor on clinical outcomes in patients with acute coronary syndrome (ACS) after percutaneous coronary intervention (PCI).

Methods

We retrospectively analyzed data from a “real world”, international, multi-center registry between 2003 and 2014 (n = 15,401) and assessed the impact of concomitant administration of PPIs and clopidogrel or ticagrelor on 1-year composite primary endpoint (all-cause death, re-infarction, or severe bleeding) in patients with ACS after PCI.

Results

Of 9429 patients in the final cohort, 54.8% (n = 5165) was prescribed a PPI at discharge. Patients receiving a PPI were older, more often female, and were more likely to have comorbidities. No association was observed between PPI use and the primary endpoint for patients receiving clopidogrel (adjusted HR: 1.036; 95% CI: 0.903–1.189) or ticagrelor (adjusted HR: 2.320; 95% CI: 0.875–6.151) (P_interaction = 0.2004). Similarly, use of a PPI was not associated with increased risk of all-cause death, re-infarction, or a decreased risk of severe bleeding for patients treated with either clopidogrel or ticagrelor.

Conclusions

In patients with ACS following PCI, concomitant use of PPIs was not associated with increased risk of adverse outcomes in patients receiving either clopidogrel or ticagrelor. Our findings indicate it is reasonable to use a PPI in combination with clopidogrel or ticagrelor, especially in patients with a higher risk of gastrointestinal bleeding.

An update on management of the patient presenting with non-ST-elevation acute coronary syndromes

Over 780,000 patients in the United States are diagnosed with an acute coronary syndrome (ACS) each year. As physicians, it is our responsibility to provide prompt workup, diagnosis and management of these patients. After identification of the patient with ACS and confirming there is not ST-segment elevation MI requiring immediate revascularization, physicians should pursue a work-up for non-ST-elevation acute coronary syndrome (NSTE-ACS). It is important to understand the latest best practice guidelines in the treatment and management of patients with NSTE-ACS who carry high rates of in-hospital mortality. Physicians must integrate the clinical history and examination, electrocardiogram and laboratory findings in order to properly diagnose an NSTE-ACS. Early treatment with guideline directed medical therapy is imperative even in the setting of an early invasive strategy with cardiac catheterization and percutaneous coronary intervention. The focus of this review is to discuss the appropriate strategies for evaluation and management of patients with NSTE-ACS based on the most recent ACC/AHA practice guidelines.

The Treatment of Disorders of Lipid Metabolism

BACKGROUND

Disorders of lipid metabolism are very common. They play an important role in the pathogenesis of atherosclerosis and can be effectively treated by lifestyle changes and drugs.

METHODS

This review is based on pertinent literature retrieved by a selective search.

RESULTS

The main disorders of lipid metabolism are LDL-hypercholesterolemia, hypertriglyceridemia, mixed hyperlipoproteinemia, and low HDL cholesterol. The lipoprotein(a) level can also be elevated either in isolation or in combination with other disorders of lipid metabolism. According to the current European recommendations, an LDL-cholesterol target value should be defined on the basis of the overall cardiovascular risk. If this risk is very high, as in patients with documented atherosclerosis, the target value should be set at <70 mg/dL (<1.8 mmol/L). If the risk is lower, higher target values can be set: <100 mg/dL (<2.6 mmol/L) or <115 mg/dL (<3.0 mmol/L). Lifestyle changes are an effective treatment mainly for patients with hypertriglyceridemia and mixed disorders of lipid metabolism. Lowering the LDL-cholesterol concentration with statins is by far the most important type of pharmacotherapy. Patients who cannot tolerate statins or whose cholesterol level is not adequately lowered can be given ezetimibe instead. PCSK9 antibodies have been available since the autumn of 2015; they can apparently lower the LDL-cholesterol level by more than 50% , but no endpoint trials have yet been reported. At present, they should only be given to carefully selected patients. Fibrates and omega-3 fatty acids have been found to prevent cardiovascular events in monotherapy trials but yield no added benefit when given together with statins. The design of these trials was faulty, however, and the utility of such combinations in patients with mixed disorders of lipid metabolism or hypertriglyceridemia cannot yet be definitively assessed.

CONCLUSION

There is a causal relationship between hypercholesterolemia and the risk of vascular and cardiovascular events. A reduction of LDL cholesterol lessens the risk of cardiovascular events.

A novel troponin I rule-out value below the upper reference limit for acute myocardial infarction

OBJECTIVE

To determine cut-off values for a recently introduced high sensitive cardiac troponin assay (hs-cTnI) which provide similar sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV) for acute myocardial infarction (AMI) as known cut-off values for an hs-cTnT assay.

METHODS

A prospective observational study was performed. Hs-cTnT (Roche) and hs-cTnI (Abbott) were measured in consecutive patients with symptoms suggestive of AMI. Representative measurements (obtained at least 3 h after chest pain has started) and serial measurements with a time delay between 2.5 h and 4.5 h were used to determine cut-off levels. Two independent clinicians adjudicated the final diagnosis.

RESULTS

1490 patients were included in the study of whom 114 (8%) received a final diagnosis of AMI. Receiver operating characteristics analysis showed no statistically significant differences in the areas under the curve between the two assays. Cut-off values for representative hs-TnI were found to be as follows: rule-out: 10 ng/L (sensitivity: 98.2%; 95% CI 95.7% to 100.0% and NPV: 99.8%; 99.5% to 100.0%); rule-in: 70 ng/L (specificity: 90.8%; 89.3% to 92.4% and PPV: 39.7%; 36.1% to 43.3%). For serial measurements we found a Δ rule-out cut-off value of 20 ng/L (sensitivity: 94.9%; 88.0% to 100.0% and NPV: 98.7%; 96.9% to 100.0%) and Δ rule-in cut-off values of 100 ng/L (specificity: 92.7%; 87.9% to 95.8% and PPV: 57.6%; 39.4% to 74.0%) and 300% (specificity: 93.8%; 90.4% to 97.2% and PPV: 61.3%; 51.1% to 71.5%).

CONCLUSIONS

Cut-off values for hs-cTnI measurements are determined which allow a similar diagnostic classification as compared with hs-cTnT. Importantly, for a rule-out paradigm this cut-off value is unmistakably lower than the upper reference limit.

Revascularization in complex multivessel coronary artery disease after FREEDOM. Is there an indication for PCI and drug-eluting stents?

Diabetes mellitus is a highly prevalent metabolic disorder frequently associated with the development of coronary atherosclerosis. Myocardial revascularization assumes a central role in the treatment of diabetic patients with coronary artery disease. Although coronary artery bypass grafting (CABG) is in principle the revascularization modality of choice in diabetic patients with complex, multivessel disease, percutaneous coronary interventions (PCI) using new-generation drug-eluting stents (DES) remain a valuable treatment option for properly selected diabetic patients. Defining the appropriate revascularization strategy is often a challenging task that requires tailored approaches, accounting for individual patient surgical risk, anatomical configurations, and the technical feasibility of each procedure in addition to careful judgment of the possible benefits and risks inherent to PCI and CABG. Evidence is building that advances in DES technology may mitigate at least in part some of the adverse vascular effects of diabetes; whether this may translate to PCI outcomes comparable with those achieved by CABG is under investigation in randomized trials currently underway. This review article summarizes the indications for myocardial revascularization across the spectrum of clinical presentations and critically discusses current evidence and future perspectives regarding the value of each revascularization mode (CABG vs. PCI) in patients with diabetes.

Stroke Prevention in Atrial Fibrillation: A Clinical Perspective on Trials of the Novel Oral Anticoagulants

Atrial fibrillation (AF) is a common heart rhythm disturbance; its incidence increases with age, and it is also an independent risk factor for stroke. Anticoagulation has been proven as the most effective way to reduce the risk of stroke in patients with AF, and vitamin K antagonists have been used for decades as the gold standard treatment. Vitamin K antagonists have a narrow therapeutic window in addition to variable pharmacokinetics and pharmacodynamics, and they frequently interact with food and other drugs, requiring coagulation monitoring to ensure balance between safety and efficacy. The novel oral anticoagulants (NOACs) dabigatran, rivaroxaban, apixaban, and edoxaban selectively target either thrombin or Factor Xa and have predictable pharmacologic profiles, removing the need for routine coagulation monitoring. This article summarizes phase III data in patient subtypes and discusses controversies surrounding AF management with these agents. Results indicate that NOACs in non-valvular AF have an overall improved efficacy-safety profile compared with warfarin. Significantly fewer fatal bleeding events were observed in patients randomized to rivaroxaban, apixaban, or edoxaban compared with those on warfarin, and significant reductions in the incidence of life-threatening bleeding were observed in patients randomized to dabigatran. All four pivotal trials testing the NOACs against warfarin showed significantly lower rates of intracranial bleeding in patients administered NOACs. These results suggest that wider use of NOACs has the potential to improve outcomes for most patients with AF.

A randomized trial to compare the safety of rivaroxaban vs aspirin in addition to either clopidogrel or ticagrelor in acute coronary syndrome: The design of the GEMINI-ACS-1 phase II study

Dual antiplatelet therapy (DAPT), the combination of aspirin and a P2Y12 inhibitor, given for 12 months remains the standard of care after presentation with acute coronary syndrome (ACS) because it has been shown to be associated with a significant reduction in ischemic events compared with aspirin monotherapy. The factor Xa inhibitor rivaroxaban was shown to be associated with a significant reduction in the composite of cardiovascular death, myocardial infarction, and stroke, and resulted in a nominal reduction in cardiovascular death, when added to background DAPT in the ATLAS ACS 2-TIMI 51 trial; however, there was excessive bleeding with this "triple-therapy" approach. The combination of rivaroxaban with P2Y12 inhibition in a "dual-pathway" approach may be an effective therapeutic regimen for the treatment of ACS, given the known importance of P2Y12 inhibition after stenting and intriguing data that the combination of an anticoagulant with clopidogrel after stenting in patients with atrial fibrillation appears an attractive option to this patient population. GEMINI-ACS-1 is a prospective, randomized, double-dummy, double-blind, active-controlled trial that will assess the safety of dual antithrombotic therapy (rivaroxaban [2.5 mg twice daily] + P2Y12 inhibitor) as compared with DAPT (aspirin [100 mg] + P2Y12 inhibitor) within 10 days of an ACS event in 3,000 patients. Patients will be randomized in a 1:1 ratio stratified by intended P2Y12 inhibitor use (clopidogrel 75 mg daily or ticagrelor 90 mg twice daily), with 1500 patients expected in each P2Y12 inhibitor strata. The primary end point is Thrombolysis in Myocardial Infarction clinically significant bleeding (major, minor, or requiring medical attention). The exploratory efficacy determination will be a composite of cardiovascular death, myocardial infarction, ischemic stroke, and stent thrombosis. GEMINI-ACS-1 will assess the safety and feasibility of dual antithrombotic therapy with rivaroxaban and a P2Y12 inhibitor compared with conventional DAPT for the treatment for patients with recent ACS.

The development and application of a high-sensitivity immunoassay for cardiac myosin-binding protein C

Cardiac troponins (cTns) are released and cleared slowly after myocardial injury. Cardiac myosin-binding protein C (cMyC) is a similar cardiac-restricted protein that has more rapid release and clearance kinetics. Direct comparisons are hampered by the lack of an assay for cMyC that matches the sensitivity of the contemporary assays for cTnI and cTnT. Using a novel pair of monoclonal antibodies, we generated a sensitive assay for MyC on the Erenna platform (Singulex) and compared serum concentrations with those of cTnI (Abbott) and cTnT (Roche) in stable ambulatory cardiac patients without evidence of acute cardiac injury or significant coronary artery stenoses. The assay for cMyC had a lower limit of detection of 0.4 ng/L, a lower limit of quantification (LLoQ) of 1.2 ng/L (LLoQ at 20% coefficient of variation [CV]) and reasonable recovery (107.1 ± 3.7%; mean ± standard deviation), dilutional linearity (101.0 ± 7.7%), and intraseries precision (CV, 11 ± 3%) and interseries precision (CV, 13 ± 3%). In 360 stable patients, cMyC was quantifiable in 359 patients and compared with cTnT and cTnI measured using contemporary high-sensitivity assays. cMyC concentration (median, 12.2 ng/L; interquartile range [IQR], 7.9-21.2 ng/L) was linearly correlated with those for cTnT (median, <3.0 ng/L; IQR, <3.0-4.9 ng/L; R = 0.56, P < 0.01) and cTnI (median, 2.10 ng/L; IQR, 1.3-4.2 ng/L; R = 0.77, P < 0.01) and showed similar dependencies on age, renal function, and left ventricular function. We have developed a high-sensitivity assay for cMyC. Concentrations of cMyC in clinically stable patients are highly correlated with those of cTnT and cTnI. This high correlation may enable ratiometric comparisons between biomarkers to distinguish clinical instability.

Comparison of the Global Registry of Acute Coronary Events Risk Score Versus the Can Rapid Risk Stratification of Unstable Angina Patients Suppress Adverse outcomes With Early Implementation of the ACC/AHA Guidelines Risk Score to Predict In-Hospital Mortality and Major Bleeding in Acute Coronary Syndromes

Risk assessment plays a major role in the management of acute coronary syndrome. The aim was to compare the performance of the Global Registry of Acute Coronary Events (GRACE) and the Can Rapid risk stratification of Unstable angina patients Suppress Adverse outcomes with Early implementation of the American College of Cardiology/American Heart Asociation guidelines (CRUSADE) risk scores to predict in-hospital mortality and major bleeding (MB) in 1,587 consecutive patients with acute coronary syndrome. In-hospital deaths and bleeding complications were prospectively collected. Bleeding complications were defined according to CRUSADE and Bleeding Academic Research Consortium (BARC) criteria. During the hospitalization, 71 patients (4.5%) died, 37 patients (2.3%) had BARC MB and 34 patients (2.1%) had CRUSADE MB. Receiver operating characteristic curves analyses showed GRACE risk score has better discrimination capacity than CRUSADE risk score for both, mortality (0.86 vs 0.79; p = 0.018) and BARC MB (0.80 vs 0.73; p = 0.028), but similar for CRUSADE MB (0.79 vs 0.79; p = 0.921). Both scores had low discrimination for predicting MB in the elderly (>75 years) and patients with atrial fibrillation, whereas CRUSADE risk score was especially poor for predicting MB in patients with <60 ml/min/1.73 m(2) or those treated with new antiplatelets. Reclassification analyses showed GRACE risk score was associated with a significant improvement in the predictive accuracy of CRUSADE risk score for predicting mortality (net reclassification improvement: 22.5%; p <0.001) and MB (net reclassification improvement: 17.6%; p = 0.033) but not for CRUSADE MB. In conclusion, GRACE risk score has a better predictive performance for predicting both in-hospital mortality and BARC MB. In light of these findings, we propose the GRACE score as a single score to predict these in-hospital complications.

Present and Future of Cardiac Troponin in Clinical Practice: A Paradigm Shift to High-Sensitivity Assays

Despite its wide utilization and central role in the evaluation of patients with potential ischemic symptoms, misconceptions and confusion about cardiac troponin (cTn) prevail. The implementation of high-sensitivity (hs) cTn assays in clinical practice has multiple potential advantages provided there is an education process tied to the introduction of these assays that emphasizes the appropriate utilization of the test. Several diagnostic strategies have been explored with hs-cTn assays, including the use of undetectable values, accelerated serial hs-cTn sampling, hs-cTn measurements in combination with a clinical-risk score, and the use of a single hs-cTn measurement with a concentration threshold tailored to meet a clinical need. In this document we discuss basic concepts that should facilitate the integration of hs-cTn assays into clinical care in years to come.

Transitioning high sensitivity cardiac troponin I (hs-cTnI) into routine diagnostic use: More than just a sensitivity issue

OBJECTIVES

High sensitivity cardiac troponin T and I (hs-cTnT and hs-cTnI) assays show analytical, diagnostic and prognostic improvement over contemporary sensitive cTn assays. However, given the importance of troponin in the diagnosis of myocardial infarction, implementing this test requires rigorous analytical and clinical verification across the total testing pathway. This was the aim of this study.

DESIGN AND METHODS

Analytical verification included assessment of critical outlier frequency, for hs-cTnI and cTnI assays. Concordance for paired cTnI and hs-cTnI measurements (n=1096) was verified using 99th percentiles for both genders (cTnI: 30 ng/L, hs-cTnI: 25 ng/L) and for men and women separately (hs-cTnI: M: 34;F: 16 ng/L). Discordant data was correlated with clinical and laboratory information. Diagnosis of Acute Coronary Syndrome (ACS) or Non-ACS was adjudicated by two cardiologists independently.

RESULTS

The hs-cTnI assay showed a lower (10-fold) critical outlier rate (0.091%) and more detectable results above the limit of detection (LOD) (23.4%) and 99th percentile (2.4%), compared to cTnI. Analytical concordance between the two assays was high (94.5%) but decreased (91.7%) when gender-specific hs-cTnI cut-offs were used. The hs-cTnI assay gave fewer false negatives (up to 1.0%) but disproportionately more false positives (up to 6.7%) overall, which improved (3.9%) for serial measurements.

CONCLUSIONS

Laboratories should analytically and clinically verify hs-cTn assays before use, with attention to performance and the clinical and diagnostic algorithms that support appropriate testing and result interpretation. Work in the pre- and post-analytical phases is necessary to augment the analytical improvement in the new era of troponin testing.

Right bundle branch block and SIQIII-type patterns for risk stratification in acute pulmonary embolism

INTRODUCTION

Risk stratification in acute pulmonary embolism (PE) is crucial for identification of patients with poor prognosis. We aimed to investigate the ECG alterations of right bundle branch block (RBBB) and SIQIII-type patterns for risk stratification in acute PE.

MATERIALS AND METHODS

Retrospective analysis of PE patients, treated in the Internal Medicine Department, was performed. Patients with RBBB and/or SIQIII-type were compared with those without both patterns. Logistic regression models for association between these ECG alterations and respectively right ventricular dysfunction (RVD), high-risk PE status and myocardial injury were computed.

RESULTS

175 patients were included for this retrospective analysis. Total study sample comprised 37 PE patients (21.1%) with RBBB and/or SIQIII-type patterns and 138 PE patients (78.9%) without both signs. Heart rate (97.4±17.2 vs. 93.2±26.8/min, P=0.021), cardiac troponin I values (0.19±0.38 vs. 0.11±0.24, P=0.003) and percentage of patients with RVD (83.9% vs. 52.7%, P=0.005) were significantly higher in PE patients with RBBB and/or SIQIII-type patterns compared to PE patients without both ECG alterations. Multi-variate logistic regression models adjusted for age and gender revealed significant associations between RBBB and RVD (OR3.942, 95% CI1.054-14.747, P=0.042) and between SIQIII-type patterns and RVD (OR5.667, 95% CI1.144-28.071, P=0.034). The association between RBBB and cardiac injury (cTnI>0.4ng/ml) (OR2.531, 95% CI 0.973-6.583, P=0.06) showed a borderline significance, while the association between SIQIII-type patterns and cardiac injury was significant (OR3.956, 95% CI1.309-11.947, P=0.015).

CONCLUSIONS

RBBB and SIQIII-type patterns were both associated with RV overload and cardiac injury. RBBB and SIQIII-type patterns were connected with 3.9-fold and 5.7-fold elevated risk of RVD, respectively.

Reviewing the controversy surrounding pre-treatment with P2Y12 inhibitors in acute coronary syndrome patients

Pretreatment with oral P2Y12 inhibitors occurs each time clopidogrel, prasugrel, ticagrelor are given to patients with suspected coronary artery disease before definition of the coronary anatomy. In acute coronary syndromes, the practice of administering oral P2Y12 inhibitors upstream has been the object of significant controversy in recent years, following the publication of two trials of pretreatment in non-ST-segment elevation acute coronary syndromes and ST-segment elevation myocardial infarction, respectively. The introduction in the market of cangrelor - the first intravenous P2Y12 inhibitor - represents a new opportunity but also a new challenge for clinicians. This article reviews current recommendations and supporting evidence surrounding pretreatment with oral and intravenous P2Y12 inhibitors in patients with acute coronary syndromes.