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)

Translation of acute coronary syndrome therapies: from evidence to routine clinical practice

BACKGROUND

The use of evidence-based therapies has improved the outcome of patients with acute coronary syndrome (ACS), but there is a time lag between the generation of clinical evidence and its application in routine clinical practice. We sought to quantify temporal lags in the lifecycle of American College of Cardiology (ACC)/American Heart Association (AHA) class IA ACS therapies.

METHODS

Using current and historical ACC/AHA guideline publications, we retrieved publication dates of pivotal clinical trials (PCTs) and class IA guideline-recommended therapies for patients with ST-elevation myocardial infarction (STEMI) and unstable angina (UA)/non-STEMI (NSTEMI). Clinical practice uptake data for each therapy were retrieved from the National Registry for Myocardial Infarction, Can Rapid Risk Stratification of Unstable Angina Patients Suppress Adverse Outcomes with Early Implementation of the ACC/AHA Guidelines, and Acute Coronary Treatment and Intervention Outcomes Network Registry-Get with the Guidelines, which are registries containing publicly available peer-reviewed data. Descriptive data were calculated and compared for each phase of the evidence lifecycle for both STEMI and UA/NSTEMI drug classifications.

RESULTS

We identified 11 class IA- and 4 class IB/IC-recommended therapies for acute, inhospital, and discharge use for patients with STEMI or UA/NSTEMI. The median time lags were 2 years (interquartile range [IQR], 1-4 years) from PCT to practice guideline recommendation, 14 years (IQR, 11-15 years) from guideline recommendation to 90% practice uptake, and overall, a 16-year median (IQR, 13-19 years) from PCT to 90% practice uptake.

CONCLUSIONS

The time of PCT publication to meaningful uptake of class IA ACS therapies into clinical practice took a median of 16 years. This significant time lag indicates systemic barriers to the translation of therapeutics into routine clinical practice.

Relation between stent thrombosis and calcium channel blocker after drug-eluting stent implantation: Kumamoto Intervention Conference Study (KICS) registry

BACKGROUND

Stent thrombosis (ST) has emerged as a severe complication of percutaneous coronary intervention (PCI). Since the occurrence of ST is lower in Japan than Western countries, there are few data to predict ST after drug-eluting stent (DES) implantation in Japan. We examined the independent predictors of ST incidence after DES implantation in Japanese patients, including the use of calcium channel blockers (CCBs).

METHODS AND RESULTS

We used data from the Kumamoto Intervention Conference Study registry. There were 6286 consecutive patients enrolled from June 2008 to March 2011. Among them, we analyzed 3493 patients who underwent DES implantation. The incidence of definite/probable ST throughout a median follow-up period of 364 days was 0.57% (20 patients). There were 8 patients with early ST (within 30 days), 8 patients with late ST (between 31 and 365 days), and 4 patients with very late ST (after 1 year). The frequency of CCB use was significantly lower in ST than non-ST patients (25.0% versus 51.4%, respectively, p=0.016). Multiple regression analysis showed that longer stent length (p=0.034), acute coronary syndrome (p=0.039), and the absence of CCB use (p=0.046) were significant and independent predictors of ST within 1 year.

CONCLUSIONS

These results suggest that CCB use may be associated with a decreased risk of ST after DES implantation within 1 year in Japanese patients.

Drug-Eluting Stents versus Bare-Metal Stents in Taiwanese Patients with Acute Coronary Syndrome: An Outcome Report of a Multicenter Registry

BACKGROUND

The study aims to compare cardiovascular outcomes of using bare-metal stents (BMS) and drug-eluting stents (DES) in patients with acute coronary syndrome (ACS) through analysis of the database from the Taiwan ACS registry. Large domestic studies comparing outcomes of interventional strategies using DES and BMS in a Taiwanese population with ACS are limited.

METHODS AND RESULTS

Collected data regarding characteristics and cardiovascular outcomes from the registry database were compared between the BMS and DES groups. A Cox regression model was used in an unadjusted or adjusted manner for analysis. Baseline characteristics apparently varied between DES group (n = 650) and BMS group (n = 1672) such as ACS types, Killip's classifications, or coronary blood flows. Compared with the BMS group, the DES group was associated with significantly lower cumulative incidence of all-cause mortality (3.4% vs. 5.8%, p = 0.008), target vessel revascularization (TVR) (5.2% vs. 7.4%, p = 0.035), or major adverse cardiac events (MACE) (10.2% vs. 15.6%, p < 0.001) at 1 year in a real-world setting. Cox regression analysis showed the BMS group referenced as the DES group had significantly higher risk-adjusted total mortality [hazard ratio (HR) = 1.85, p = 0.026], target vessel revascularization (TVR) (HR = 1.59, p = 0.035), and MACE (HR = 1.68, p = 0.001).

CONCLUSIONS

The data show use of DES over BMS provided advantages to patients with ACS in terms of lower 1-year mortality, TVR, and MACE. The study suggests implantation of DES compared with BMS in Taiwanese patients with ACS is safe and beneficial in the real-world setting.

KEY WORDS

Acute coronary syndrome; Bare-metal stent; Cardiovascular outcome; Drug-eluting stent; Percutaneous coronary intervention.

Coronary artery manifestations of fibromuscular dysplasia

Fibromuscular dysplasia (FMD) involving the coronary arteries is an uncommon but important condition that can present as acute coronary syndrome, left ventricular dysfunction, or potentially sudden cardiac death. Although the classic angiographic "string of beads" that may be observed in renal artery FMD does not occur in coronary arteries, potential manifestations include spontaneous coronary artery dissection, distal tapering or long, smooth narrowing that may represent dissection, intramural hematoma, spasm, or tortuosity. Importantly, FMD must be identified in at least one other noncoronary arterial territory to attribute any coronary findings to FMD. Although there is limited evidence to guide treatment, many lesions heal spontaneously; thus, a conservative approach is generally preferred. The etiology is poorly understood, but there are ongoing efforts to better characterize FMD and define its genetic and molecular basis. This report reviews the clinical course of FMD involving the coronary arteries and provides guidance for diagnosis and treatment strategies.

Contemporary Patterns of Discharge Aspirin Dosing After Acute Myocardial Infarction in the United States

Background—

Accumulated data suggest that low-dose aspirin after myocardial infarction (MI) may offer similar efficacy to higher dose aspirin with reduced risk of bleeding. Few data are available on contemporary aspirin dosing patterns after MI in the United States

Methods and Results—

Aspirin dosing from 221 199 patients with MI (40.2% ST-segment–elevation MI) from 525 US hospitals enrolled in the National Cardiovascular Data Registry’s (NCDR’s) Acute Coronary Treatment and Intervention Outcomes Network Registry-Get with the Guidelines were described, overall and in clinically relevant subgroups. High-dose aspirin was defined as 325 mg and low dose as 81 mg. Between January 2007 and March 2011, 60.9% of patients with acute MI were discharged on high-dose aspirin, 35.6% on low-dose aspirin, and 3.5% on other doses. High-dose aspirin was prescribed at discharge to 73.0% of patients treated with percutaneous coronary intervention and 44.6% of patients managed medically. Among 9075 patients discharged on aspirin, thienopyridine, and warfarin, 44.0% were prescribed high-dose aspirin. Patients with an in-hospital major bleeding event were also frequently discharged on high-dose aspirin (56.7%). A 25-fold variation in the proportion prescribed high-dose aspirin at discharge was observed across participating centers.

Conclusions—

Most US patients with MI continue to be discharged on high-dose aspirin. Although aspirin dosing after percutaneous coronary intervention largely reflected prevailing guidelines before 2012, high-dose aspirin was prescribed with similar frequency in medically managed patients and to those in categories expected to be at high risk for bleeding. Wide variability in the proportional use of high-dose aspirin across centers suggests significant influence from local practice habits and uncertainty about appropriate aspirin dosing.

Predictive value of the novel risk score BETTER (BiomarkErs and compuTed Tomography scorE on Risk stratification) for patients with unstable angina

BACKGROUND

The Braunwald classification and TIMI (Thrombolysis In Myocardial Infarction) risk score are used to stratify cardiovascular risk in patients with unstable angina (UA). However, these scores have a limited capacity in the practice of cardiology.

OBJECTIVES

This study sought to develop a new score, based on blood biomarkers and coronary computed tomographic angiography (CCTA) characteristics, for patients with UA.

PATIENTS AND METHODS

The study group consisted of 201 patients with confirmed UA. Follow-up time was 1 year; major adverse cardiac events (MACEs) included cardiovascular death, recurrent acute coronary syndrome (ACS), and re-admission to hospital. Blood biomarkers including high-sensitivity cardiac troponin T (Hs-cTnT), high-sensitivity C-reactive protein (Hs-CRP), myeloperoxidase (MPO) N-terminal pro-B-type natriuretic peptide (NT-proBNP), and ischemia-modified albumin (IMA) were measured. CCTA characteristics such as stenosis, plaque, epicardial fat volume (EFV), and calcification were evaluated. After analysis of relationships, the novel risk BETTER (BiomarkErs and compuTed Tomography scorE on Risk stratification) score was assessed in 201 patients.

RESULTS

In all, 25 MACEs (12.44 %) occurred: 2 cardiac deaths (1.00 %), 13 non-fatal myocardial infarctions (6.47 %), 10 recurrent ACS and re-admission in hospital (4.96 %). Serum levels of MPO, NT-proBNP, Hs-TnT, Hs-CRP, and IMA were correlated with MACEs (r = 0.20, r = 0.40, r = 0.18, r = 0.24, p < 0.01, respectively; r = 0.12, p > 0.05). CCTA characteristics of stenosis, plaque, EFV, and calcification were significantly correlated with MACEs (r = 0.53, r = 0.57, r = 0.42, and r = 0.52, all p < 0.01 respectively) and were significantly higher in the MACEs group than in the non-MACEs group. Thus, a new risk score was created combining biomarkers and CCTA statistics into a Cox multivariable for risk prediction of 1-year MACEs: BETTER risk score = MPO•0.1 + Hs-TnT•50 + Hs-CRP•0.4 + stenosis•9 + plaque•13 + EFV•0.2. The areas under the curve (AUC) for the prediction by Hs-cTnT, Hs-CRP, and MPO were 0.536 (95 % CI 0.409-0.662), 0.745 (95 % CI 0.641-0.850), and 0.650 (95 % CI 0.541-0.760), respectively. The AUC for the prediction of CCTA characteristics of stenosis, plaque, and EFV were 0.905 (95 % CI 0.860-0.950), 0.912 (95 % CI 0.867-0.957), and 0.835 (95 % CI 0.752-0.917), respectively. In addition, the AUC was 0.621 (95 % CI 0.492-0.750) for the Braunwald classification and 0.680 (95 % CI 0.559-0.801) for the TIMI score. The AUC for the BETTER risk score was 0.937 (95 % CI 0.902-0.972).

CONCLUSION

The BETTER risk score is new tool specifically developed for patients with UA. The score displays higher prediction accuracy in terms of discrimination and calibration than other currently available scores for risk stratification.

Contrast Volume-to-Creatinine Clearance Ratio Predicts the Risk of Contrast-Induced Nephropathy After Percutaneous Coronary Intervention in Patients With Reduced Ejection Fraction

We determined a relatively safe contrast media volume-to-creatinine clearance (V/CrCl) cutoff value to avoid contrast-induced nephropathy (CIN) after percutaneous coronary intervention (PCI) in patients (n = 111) with reduced ejection fraction (<40%). Improved prediction of CIN in these patients would be useful. Multivariate regression models were used to evaluate whether V/CrCl is an independent risk factor for CIN. Nine (8.1%) patients developed CIN. The V/CrCl was significantly (P = .023) higher in patients with CIN than in those without. The incidence of CIN in patients with the highest tertile of V/CrCl was significantly higher than the middle and lowest tertiles (18.4% vs. 2.7% and 2.8%; P = .013). After adjusting for other potential risk factors, a V/CrCl ≥3.87 remained significantly associated with risk of CIN. A V/CrCl <3.87 might be valuable in predicting the risk of CIN in patients with reduced ejection fraction undergoing PCI.

Perioperative management of combined carotid and coronary artery bypass grafting procedures

The objective of this review is to provide a high level overview on current thinking for treatment of patients with combined carotid and coronary artery disease given that these patients are at higher risk of adverse cardiac events, stroke, and death. This review discusses (1) the current literature addressing perioperative stroke risk in the setting of coronary artery bypass graft, (2) the literature regarding different surgical approaches when both carotid and coronary revascularization are being considered, and (3) the data available to guide optimal management of this complex patient population to minimize complications regardless of the surgical approach taken.

Heart rate variability measured early in patients with evolving acute coronary syndrome and 1-year outcomes of rehospitalization and mortality

OBJECTIVE

This study sought to examine the prognostic value of heart rate variability (HRV) measurement initiated immediately after emergency department presentation for patients with acute coronary syndrome (ACS).

BACKGROUND

Altered HRV has been associated with adverse outcomes in heart disease, but the value of HRV measured during the earliest phases of ACS related to risk of 1-year rehospitalization and death has not been established.

METHODS

Twenty-four-hour Holter recordings of 279 patients with ACS were initiated within 45 minutes of emergency department arrival; recordings with ≥18 hours of sinus rhythm were selected for HRV analysis (number [N] =193). Time domain, frequency domain, and nonlinear HRV were examined. Survival analysis was performed.

RESULTS

During the 1-year follow-up, 94 patients were event-free, 82 were readmitted, and 17 died. HRV was altered in relation to outcomes. Predictors of rehospitalization included increased normalized high frequency power, decreased normalized low frequency power, and decreased low/high frequency ratio. Normalized high frequency >42 ms(2) predicted rehospitalization while controlling for clinical variables (hazard ratio [HR] =2.3; 95% confidence interval [CI] =1.4-3.8, P=0.001). Variables significantly associated with death included natural logs of total power and ultra low frequency power. A model with ultra low frequency power <8 ms(2) (HR =3.8; 95% CI =1.5-10.1; P=0.007) and troponin >0.3 ng/mL (HR =4.0; 95% CI =1.3-12.1; P=0.016) revealed that each contributed independently in predicting mortality. Nonlinear HRV variables were significant predictors of both outcomes.

CONCLUSION

HRV measured close to the ACS onset may assist in risk stratification. HRV cut-points may provide additional, incremental prognostic information to established assessment guidelines, and may be worthy of additional study.

Characteristics of new P2Y12 inhibitors: selection of P2Y12 inhibitors in clinical practice

The options for antithrombotic therapy have recently been expanded, facilitating optimal tailored treatment. Dual antiplatelet therapy with aspirin and an approved adenosine diphosphate P2Y12 receptor antagonist is recommended for the management of patients with acute coronary syndromes (ACS). However, there are a number of controversies: which P2Y12 inhibitor to choose; how long should antiplatelet therapy be used so as to prevent thrombotic events and minimize bleeding risks; whether to use drug-eluting (DES) or bare-metal stents (BMS) and how to manage the individual variability in response to clopidogrel. Clopidogrel in combination with aspirin has been the standard dual antiplatelet regimen for ACS. The new, more potent P2Y12 inhibitors, prasugrel and ticagrelor, have shown improved antithrombotic effects compared with clopidogrel in patients with ACS (with or without ST-segment elevation myocardial infarction) in landmark trials, even if they were associated with an increased risk of major bleeding. Different pharmacogenetic and pharmacodynamic characteristics may explain, in part, the different pharmacologic and clinical responses to these antiplatelet agents. Importantly, both clopidogrel and prasugrel are prodrugs, i.e., they need to be converted in vivo into active metabolites that selectively and irreversibly bind the P2Y12 receptor. Unlike clopidogrel, however, common functional cytochrome P450 genetic variants do not affect prasugrel active metabolite levels or inhibition of platelet aggregation. In contrast, ticagrelor is not a prodrug (i.e., does not require hepatic metabolism to exert its antiplatelet effect) and represents the first oral P2Y12 receptor antagonist that is reversibly bound. Similar to prasugrel, ticagrelor achieves greater and more rapid inhibition of platelet function than clopidogrel. Evidence suggests that the new P2Y12 antagonists may offer improved antithrombotic effects compared with clopidogrel in selected patients for the optimal management of ACS in clinical practice.

Clinical and economic studies of eptifibatide in coronary stenting

Platelet adhesion and aggregation at the site of coronary stenting can have catastrophic clinical and economic consequences. Therefore, effective platelet inhibition is vital during and after percutaneous coronary intervention. Eptifibatide is an intravenous antiplatelet agent that blocks the final common pathway of platelet aggregation and thrombus formation by binding to glycoprotein IIb/IIIa receptors on the surface of platelets. In clinical studies, eptifibatide was associated with a significant reduction of mortality, myocardial infarction, or target vessel revascularization in patients with acute coronary syndrome undergoing percutaneous coronary intervention. However, recent trials conducted in the era of dual antiplatelet therapy and newer anticoagulants failed to demonstrate similar results. The previously seen favorable benefit of eptifibatide was mainly offset by the increased risk of bleeding. Current American College of Cardiology/American Heart Association guidelines recommend its use as an adjunct in high-risk patients who are undergoing percutaneous coronary intervention with traditional anticoagulants (heparin or enoxaparin), who are not otherwise at high risk of bleeding. In patients receiving bivalirudin (a newer safer anticoagulant), routine use of eptifibatide is discouraged except in select situations (eg, angiographic complications). Although older pharmacoeconomic studies favor eptifibatide, in the current era of P2Y12 inhibitors and newer safer anticoagulants, the increased costs associated with bleeding make the routine use of eptifibatide an economically nonviable option. The cost-effectiveness of eptifibatide with the use of strategies that decrease the bleeding risk (eg, transradial access) is unknown. This review provides an overview of key clinical and economic studies of eptifibatide well into the current era of potent antiplatelet agents, novel safer anticoagulants, and contemporary percutaneous coronary intervention.

Variability of individual platelet reactivity over time in patients treated with clopidogrel: insights from the ELEVATE-TIMI 56 trial

BACKGROUND

The degree of antiplatelet response to clopidogrel has been associated with clinical outcomes. Studies have investigated whether adjustment of antiplatelet therapies based on a single platelet function test is beneficial.

OBJECTIVES

The aim of the study was to test the stability of platelet reactivity measurements over time among patients treated with standard and double doses of clopidogrel.

METHODS

The ELEVATE-TIMI 56 (Escalating Clopidogrel by Involving a Genetic Strategy-Thrombolysis In Myocardial Infarction 56) investigators genotyped 333 patients with coronary artery disease and randomized them to various clopidogrel regimens. Patients with at least 2 platelet function results on the same maintenance dose of clopidogrel (75 mg or 150 mg) were analyzed. Platelet aggregation was measured using P2Y12 reaction units (PRU).

RESULTS

In total, the mean platelet reactivity and the total number of nonresponders (PRU ≥230) with clopidogrel did not change between 2 periods for the 75-mg (22.4% vs. 21.9%; p = 0.86) and 150-mg doses of clopidogrel (11.5% vs. 11.5%; p = 1.00). In contrast, when evaluating each patient individually, 15.7% of patients taking clopidogrel 75 mg and 11.4% of patients taking 150 mg had a change in their responder status when tested at 2 different time points (p < 0.001). Despite being treated with the same dose of clopidogrel, >40% of patients had a change in PRU >40 on serial sampling, which approximates the average PRU difference caused by increasing the clopidogrel dose from 75 mg to 150 mg.

CONCLUSIONS

Measurements of platelet reactivity vary over time in a significant proportion of patients. Thus, treatment adjustment according to platelet function testing at a single time point might not be sufficient for guiding antiplatelet therapy in clinical or research settings. (Escalating Clopidogrel by Involving a Genetic Strategy-Thrombolysis In Myocardial Infarction 56 [ELEVATE-TIMI 56]; NCT01235351).

Diagnostic accuracy of sensitive or high-sensitive troponin on presentation for myocardial infarction: a meta-analysis and systematic review

Background

Recently, high-sensitive troponin (hsTrop) assays consistent with professional societies’ recommendations became available. We aimed to summarize the evidence on the diagnostic accuracy of hsTrop on presentation.

Methods

We searched electronic databases for studies evaluating the diagnostic accuracy of hsTrop in suspected acute coronary syndrome (ACS) patients. Random effect meta-analyses and meta-regression were performed. Primary and secondary analyses were restricted to studies using conventional Trop and hsTrop in the reference standard, respectively.

Results

Fifteen studies with a total of 8,628 patients met the inclusion criteria for the primary analysis. hsTrop T (Hoffman-La Roche Ltd) and hsTrop I (Siemens) had sensitivities of 0.89 (95% confidence interval [CI]: 0.86–0.91) and 0.90 (95% CI: 0.87–0.92) and specificities of 0.79 (95% CI: 0.77–0.80) and 0.89 (95% CI: 0.87–0.90), respectively. There was no statistically significant difference in the area under the curve between hsTrop (95% CI: 0.920) and conventional Trop (95% CI: 0.929) at the 99th percentile (P=0.62). hsTrop at the level of detection had a sensitivity of 0.97 (95% CI: 0.96–0.98) and a specificity of 0.41 (95% CI: 0.40–0.42). The studies using a cut-off at coefficient of variance <10% as opposed to the 99th percentile for the conventional assay used for diagnosis reported higher diagnostic accuracy (relative diagnostic odds ratio =2.13, P=0.02). Five studies were included in the secondary analysis; hsTrop T (Hoffman-La Roche Ltd) had a sensitivity of 0.91 (95% CI: 0.89–0.93) and a specificity of 0.67 (95% CI: 0.63–0.70). There was significant heterogeneity among the studies.

Conclusion

hsTrop have excellent diagnostic accuracy for myocardial infarction on presentation, but may not outperform conventional Trop assays. The variation among the studies can be explained, in part, by the cut-off used for conventional Trop assays.

When is evidence sufficient for decision-making? A framework for understanding the pace of evidence adoption

Translation of medical evidence into practice has not kept pace with the growth of medical technology and knowledge. We present three case studies--statins, drug eluting stents and bone marrow transplantation for breast cancer--to propose a framework for describing five factors that may influence the rate of adoption. The factors are: validity, reliability and maturity of the science available before widespread adoption; communication of the science; economic drivers; patients' and physicians' ability to apply published scientific findings to their specific clinical needs; and incorporation into practice guidelines.

Duration of eptifibatide infusion after percutaneous coronary intervention and outcomes among high-risk patients with non-ST-segment elevation acute coronary syndrome: insights from EARLY ACS

BACKGROUND AND OBJECTIVES

Eptifibatide is indicated during percutaneous coronary intervention (PCI) with continuation for 18-24 hours post procedure but is associated with bleeding. We examined the efficacy and safety of shorter post-PCI eptifibatide infusions in high-risk non-ST-segment elevation acute coronary syndrome (NSTE ACS) patients.

METHODS

EARLY ACS patients treated with PCI and eptifibatide were grouped by post-procedure infusion duration: <10, 10-13, 13-17, and 17-25 (per protocol) hours. Adjusted estimated event rates for 96-hour death/myocardial infarction (MI)/recurrent ischaemia requiring urgent revascularization (RIUR), 30-day death/MI, post-PCI packed red blood cell (PRBC) transfusion, and GUSTO (Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries) moderate/severe bleeding were obtained using inverse-propensity weighting to account for informative censoring of infusions.

RESULTS

Among 3271 eptifibatide-treated PCI patients, there were 66 96-hour death/MI/RIUR events, 94 30-day death/MI events, 127 PRBC transfusions, and 115 GUSTO moderate/severe bleeds. Compared with per protocol, patients receiving post-PCI infusions <10 hours had similar adjusted estimated rates of 96-hour death/MI/RIUR (absolute difference 0.021 higher; 0.040 vs. 0.019, 95% CI -0.023 to 0.064; p=0.35) and 30-day death/MI (0.020 higher; 0.046 vs. 0.026, 95% CI -0.021 to 0.062; p=0.34). There were also no differences in ischaemic outcomes between infusions of 10-17 hours and per-protocol infusions. Adjusted estimated rates of PRBC transfusion were higher for the <10-hour infusion group compared with per protocol (0.048 higher; 0.079 vs. 0.031, 95% CI 0.005 to 0.091, p=0.03) but were similar for other groups. Adjusted GUSTO moderate/severe bleeding rates were similar to per-protocol rates for all groups.

CONCLUSIONS

In high-risk NSTE ACS patients, post-PCI eptifibatide infusions <18 hours were not associated with worse ischaemic outcomes. Shorter eptifibatide infusions in this population may be feasible.

Effects of angiotensin-converting enzyme inhibitors and beta blockers on clinical outcomes in patients with and without coronary artery obstructions at angiography (from a Register-Based Cohort Study on Acute Coronary Syndromes)

We sought to determine the effectiveness of angiotensin-converting enzyme (ACE) inhibition and β-blocker treatment as a function of the degree of coronary artery disease (CAD) obstruction at angiography. The Evaluation of Methods and Management of Acute Coronary Events registry enrolled patients who had been hospitalized for an acute coronary syndrome. There were 1,602 patients who had cardiac catheterization that were used for this analysis. The main outcome measures were evidence-based therapies prescribed at discharge and 6-month incidence of all-cause mortality. The cohort consisted of 1,252 patients with obstructive CAD (>50% luminal diameter obstructed) and 350 patients with nonobstructive CAD. Multivariate logistic regression analysis adjusted for further medications and other clinical factors was performed. Patients with nonobstructive CAD had significantly (p <0.001) higher rates of β-blocker (77.8% vs 63.3%) and lower rates of ACE-inhibitor (57.7% vs 66.4%) prescriptions. In patients with nonobstructive CAD, ACE-inhibitor therapy was clearly associated with a lower 6-month mortality (odds ratio [OR] 0.31, 95% confidence interval [CI] 0.03 to 0.78, p = 0.004). No significant association between β-blocker use and death was found. In patients with obstructive CAD, both β blockers (OR 0.47, 95% CI 0.32 to 0.67, p <0.001) and ACE inhibitors (OR 0.47, 95% CI 0.26 to 0.87, p = 0.01) were significantly associated with a reduced risk of 6-month mortality. In conclusion, ACE-inhibitor therapy seems to be an effective first-line treatment for preventing the occurrence of mortality in patients with nonobstructive CAD.

International comparisons of the management of patients with non-ST segment elevation acute myocardial infarction in the United Kingdom, Sweden, and the United States: The MINAP/NICOR, SWEDEHEART/RIKS-HIA, and ACTION Registry-GWTG/NCDR registries

Objectives

To compare management of patients with acute non-ST segment elevation myocardial infarction (NSTEMI) in three developed countries with national ongoing registries.

Background

Results from clinical trials suggest significant variation in care across the world. However, international comparisons in “real world” registries are limited.

Methods

We compared the use of in-hospital procedures and discharge medications for patients admitted with NSTEMI from 2007 to 2010 using the unselective MINAP/NICOR [England and Wales (UK); n = 137,009], the unselective SWEDEHEART/RIKS-HIA (Sweden; n = 45,069), and the selective ACTION Registry-GWTG/NCDR [United States (US); n = 147,438] clinical registries.

Results

Patients enrolled among the three registries were generally similar except those in the US who were younger but had higher rates of smoking, diabetes, hypertension, prior heart failure, and prior MI than in Sweden or in UK. Angiography and percutaneous coronary intervention (PCI) were performed more often in the US (76% and 44%) and Sweden (65% and 42%) relative to the UK (32% and 22%). Discharge betablockers were also prescribed more often in the US (89%) and Sweden (89%) than in the UK (76%). In contrast, discharge statins, angiotensin converting enzyme inhibitors/angiotensin receptor blockers (ACEI/ARB), and dual antiplatelet agents (among those not receiving PCI) were higher in the UK (92%, 79%, and 71%) than in the US (85%, 65%, 41%) and Sweden (81%, 69%, and 49%).

Conclusions

The care for patients with NSTEMI differed substantially among the three countries. These differences in care among countries provide an opportunity for future comparative effectiveness research as well as identify opportunities for global quality improvement.

Do patients treated at academic hospitals have better longitudinal outcomes after admission for non-ST-elevation myocardial infarction?

BACKGROUND

Prior studies have found that academic hospitals provide more consistent use of guideline-recommended therapies in patients with non-ST-segment myocardial infarction (NSTEMI) compared with nonacademic centers, yet it is unclear whether these care differences translate into longer-term outcome differences.

METHODS

Using data from the CRUSADE Registry linked to Center for Medicare & Medicaid Services claims, we compared 30-day and 1-year all-cause mortality among 12,194 older patients with NSTEMI (age ≥65 years) treated at 103 academic centers and 28,335 patients treated at 302 nonacademic centers from February 2003 to December 2006. Outcomes were first adjusted for clinical characteristics, followed by adjustment for hospital performance, on 13 acute and discharge guideline-recommended therapies using a shared frailty model (an extension of the Cox proportional hazard model).

RESULTS

Compared with older patients with NSTEMI treated at nonacademic hospitals, those treated at academic hospitals had greater and more consistent use of evidence-based acute and discharge therapies, were more likely to receive in-hospital revascularization (61.1% vs 54.2%; P < .0001), and had modestly lower risk-adjusted 30-day mortality after adjustment for patient-level clinical characteristics (8.9% vs 10.2%, adjusted hazard ratio [HR] 0.89, 95% CI 0.80-0.99). These differences were attenuated (HR 0.94, 95% CI 0.83-1.02) after further adjustment for hospital delivery of evidence-based treatments, yet did not persist out to 1 year (unadjusted HR 0.92, 95% CI 0.84-1.01, P = .089).

CONCLUSIONS

Patients with NSTEMI treated at academic centers are more likely to receive guideline-recommended therapies and had modestly better 30-day outcomes. Nevertheless, these differences do not persist out to 1 year.

Impact of CYP2C19 polymorphism on clinical outcome following coronary stenting is more important in non-diabetic than diabetic patients

OBJECTIVE

The aim of this study was to examine the impact of CYP2C19 genotype on clinical outcome in coronary artery disease (CAD) patients with or without diabetes mellitus (DM).

METHODS

CYP2C19 polymorphism and DM are associated with increased risk of cardiovascular events during antiplatelet therapy following stent implantation. Platelet reactivity during clopidogrel therapy and CYP2C19 polymorphism were measured in 519 CAD patients (males 70%, age 69 years) treated with stent placement. Patients were divided into two groups; DM (n=249), and non-DM (n=270), and clinical events were evaluated according to the carrier state, which included at least one CYP2C19 loss-of-function allele.

RESULTS

The level of platelet reactivity and incidence of cardiovascular events were significantly different between Carriers and non-Carriers of the non-DM (platelet reactivity: 4501+/-1668 versus 3691+/-1714AU min, P<0.01; events, 32/178 versus 2/92, P<0.01, respectively), however, there was no difference in clinical outcome in the DM group (events, 34/168 versus 14/81, respectively, P=0.57). Multivariate analysis identified CYP2C19 loss-of-function allele carriage as an independent predictor of cardiovascular events in non-DM, but not in DM (non-DM, HR 7.180, 95% CI, 1.701 to 30.298, P=0.007; DM, HR 1.374, 95% CI, 0.394 to 4.792, P=0.618).

CONCLUSION

The impact of CYP2C19 polymorphism on clinical outcome seems to be more significant in non-DM compared with DM in patients with coronary stents.

Cytochrome p450 gene variants, race, and mortality among clopidogrel-treated patients after acute myocardial infarction

BACKGROUND

Clopidogrel is recommended after acute myocardial infarction but has variable efficacy and safety, in part related to the effect of cytochrome P450 (CYP) polymorphisms on its metabolism. The effect of CYP polymorphisms on cardiovascular events among clopidogrel-treated patients after acute myocardial infarction remains controversial, and no studies to date have investigated the association of CYP variants with outcomes in black patients.

METHODS AND RESULTS

Subjects (2732: 2062 whites; 670 blacks) hospitalized with acute myocardial infarction enrolled in the prospective, multicenter TRIUMPH study were genotyped for CYP polymorphisms. The majority of whites (79%) and blacks (64.4%) were discharged on clopidogrel. Among whites, carriers of the loss-of-function CYP2C19*2 allele had significantly increased 1-year mortality (adjusted hazards ratio [HR]: 1.70; confidence interval [CI]: 1.01-2.86; P=0.046) and a trend toward increased rate of recurrent MI (adjusted HR: 2.10; CI: 0.95-4.63; P=0.066). Among blacks, increased 1-year mortality was associated with the gain-of-function CYP2C19*17 allele (adjusted HR for *1/*17 versus *1/*1: 2.02; CI: 0.92-4.44; *17/*17 versus *1/*1: 8.97; CI: 3.34-24.10; P<0.0001) and the CYP1A2*1C allele (adjusted HR for *1/*1C versus *1/*1: 1.89; CI: 0.85-4.22; *1C/*1C versus *1/*1: 4.96; CI: 1.69-14.56; P=0.014). Bleeding events were significantly more common among black carriers of CYP2C19*17 or CYP1A2*1C.

CONCLUSIONS

Both loss-of-function and gain-of-function CYP polymorphisms affecting clopidogrel metabolism are associated with increased mortality among clopidogrel-treated patients after acute myocardial infarction; the specific polymorphism and the putative mechanism vary according to race.

Long term outcomes of saphaneous vein graft intervention in elderly patients with prior coronary artery bypass graft

OBJECTIVES

To investigate the procedure characteristics and long term follow-up of percutaneous coronary intervention (PCI) for saphaneous vein graft (SVG) lesions in the elderly patients.

METHODS

From December 2005 to December 2011, 84 graft lesions were treated percutaneously. Seventeen were located at proximal anastomosis, 48 were located at SVG body, 19 were located at distal anastomosis. Primary endpoint was defined as major adverse cardiovascular events (MACE, composite of cardiac death, target vessel revascularization, acute myocardial infarction).

RESULTS

The graft age was 6.7 ± 4.0 years. Most anastomosis lesions (80.0%) presented within one year post coronary artery bypass grafting (CABG). Proximal anastomosis lesion had the lowest successful rate for PCI compared with graft body and distal anastomosis lesions (70.6% vs. 91.7%, 79.0%, P < 0.05). The distal embolic protection device was used in 19.1% of patients, most frequently used in body graft PCI (29.2%, P < 0.01). The diameter of the stent was smallest in distal anastomosis group (2.9 ± 0.4 mm, P < 0.05). The highest post dilatation pressure was required in the proximal anastomosis (17.8 ± 2.7 atm, P < 0.05). The patients were followed up for 24.3 ± 16.9 months. MACE occurred in 18.57% of patients. Incidence of MACE was highest among proximal anastomosis PCI (47.1% vs. body graft PCI 16.7%, distal anastomosis PCI 21.1%; P < 0.05). Old myocardial infarction was the predictive factor for the poor clinical outcomes (P = 0.04).

CONCLUSIONS

PCI of SVG lesions is feasible with lower success rate. PCI of ostial graft anastomosis lesions had the lowest procedure success rate and highest MACE rate compared with graft body and distal anastomosis lesions. Old myocardial infarction was a predictive factor of poor outcomes.

Effectiveness of clopidogrel dose escalation to normalize active metabolite exposure and antiplatelet effects in CYP2C19 poor metabolizers

Carriers of two copies of the loss-of-function CYP2C19*2 variant convert less clopidogrel into its active metabolite, resulting in diminished antiplatelet responses and higher cardiovascular event rates. To evaluate whether increasing the daily clopidogrel dose in poor metabolizers (PM) overcomes the effect of the CYP2C19 * 2 variant, we enrolled 18 healthy participants in a genotype-stratified, multi-dose, three-period, fixed-sequence crossover study. Six participants with the *1/*1 extensive (EM), *1/*2 intermediate (IM), and *2/*2 poor metabolizer genotypes each received 75 mg, 150 mg, and 300 mg each for 8 days. In each period, maximal platelet aggregation 4 hours post-dose (MPA4) and active metabolite area under the curve (AUC) differed among genotype groups (P < .05 for all). At day 8, PMs needed 300 mg daily and IMs needed 150 mg daily to attain a similar MPA4 as EMs on the 75 mg dose (32.6%, 33.2%, 31.3%, respectively). Similarly, PMs needed 300 mg daily to achieve active metabolite concentrations that were similar to EMs on 75 mg (AUC 37.7 and 33.5 ng h/mL, respectively). These results suggest that quadrupling the usual clopidogrel dose might be necessary to overcome the effect of poor CYP2C19 metabolism.

Pharmacogenetics in clinical practice: how far have we come and where are we going?

Recent years have seen great advances in our understanding of genetic contributors to drug response. Drug discovery and development around targeted genetic (somatic) mutations has led to a number of new drugs with genetic indications, particularly for the treatment of cancers. Our knowledge of genetic contributors to variable drug response for existing drugs has also expanded dramatically, such that the evidence now supports clinical use of genetic data to guide treatment in some situations, and across a variety of therapeutic areas. Clinical implementation of pharmacogenetics has seen substantial growth in recent years and groups are working to identify the barriers and best practices for pharmacogenetic-guided treatment. The advances and challenges in these areas are described and predictions about future use of genetics in drug therapy are discussed.

Patterns and determinants of cardiovascular drug utilization in coronary care unit patients of a tertiary care hospital

BACKGROUND

A wide variation exists in the patterns of pharmacotherapy among patients admitted with cardiovascular diseases. Very few studies have evaluated the potential determinants of drug utilization. Our objective was to evaluate the clinical characteristics and patterns of cardiovascular drug utilization among patients in coronary care unit (CCU) and assess the determinants of cardiovascular drug use among patients with coronary artery disease (CAD).

METHODS

In this retrospective cohort study, the medical records of CCU patients were reviewed independently by two trained physicians over one year. Patients were analyzed as two groups - those with CAD and without CAD. Multivariate logistic regression was done to identify the determinants of cardiovascular drug utilization in the CAD group.

RESULTS

Of 574 patients, 65% were males, 57% were <60 years. The five commonly prescribed drug classes were platelet inhibitors (88.7%), statins (76.3%), ACE-inhibitors/Angiotensin receptor blockers (72%), beta-blockers (58%) and heparin (57%). Poly-pharmacy (>5 drugs) was noticed in 71% of patients. A majority of patients had diagnosis of CAD (72.6%). CAD patients received significantly higher median number of drugs and had longer duration of CCU stay (p < 0.0001). Renal dysfunction for ACE-inhibitors [0.18 (0.09-0.36)], ST-elevation myocardial infarction for calcium channel blockers [0.29 (0.09-0.93)] and brady-arrhythmias for beta-blockers [0.3 (0.2-0.7)] were identified as determinants of decreased drug use in CAD group.

CONCLUSION

Predominance of male gender, age <60 and poly-pharmacy was observed in CCU. Antithrombotics, statins, ACE-inhibitors/Angiotensin receptor blockers and beta-blockers were the most frequently prescribed drugs. Clinical co-morbidities (renal dysfunction, arrhythmias) decreased the utilization of ACE-inhibitors, beta-blockers among CAD patients.

Association of P2Y12 gene promoter DNA methylation with the risk of clopidogrel resistance in coronary artery disease patients

Background. Clopidogrel inhibits the ADP receptor P2Y12 to keep down the platelet aggregation. The goal of our study is to investigate the contribution of P2Y12 promoter DNA methylation to the risk of clopidogrel resistance (CR). Methods. The platelet functions were measured by the VerifyNow P2Y12 assay. Applying the bisulfite pyrosequencing technology, DNA methylation levels of two CpG dinucleotides on P2Y12 promoter were tested among 49 CR cases and 57 non-CR controls. We also investigated the association among P2Y12 DNA methylation, various biochemical characteristics, and CR. Result. Lower methylation of two CpGs indicated the poorer clopidogrel response (CpG1, P = 0.009; CpG2, P = 0.022) in alcohol abusing status. Meanwhile CpG1 methylation was inversely correlated with CR in smoking patients (P = 0.026) and in subgroup of Albumin < 35 (P = 0.002). We observed that the level of DNA methylation might be affected by some clinical markers, such as TBIL, LEVF, Albumin, AST. The results also showed that the quantity of stent, fasting blood-glucose, and lower HbAC1 were the predictors of CR. Conclusions. The evidence from our study indicates that P2Y12 methylation may bring new hints to elaborate the pathogenesis of CR.

New antiplatelet agents and the role of platelet function testing in acute coronary syndromes

BACKGROUND

Dual antiplatelet therapy is a guideline mandated for patients with acute coronary syndromes (ACS). Despite its use, thrombotic events continue to occur both early and late. Platelet function testing has been used to define the in vitro effects of new antiplatelet agents, and it has been suggested that it be used to choose therapy. The role of platelet function testing, particularly with newer antiplatelet agents, remains unclear.

OBJECTIVE

We review the rationale for platelet function testing and its application in monitoring patients on antiplatelet therapy. We also review recent clinical trials of newer antiplatelet agents. On the basis of this review, we reach conclusions on the current role of antiplatelet function testing in monitoring modern antiplatelet therapy and the role of the new antiplatelet agents in the treatment of ACS.

METHODS

We reviewed recent publications on platelet function testing and clinical trials of newer antiplatelet therapies compared with clopidogrel.

RESULTS

Platelet function testing is complex, but there is now a bedside test, VerifyNow. High platelet reactivity has been associated with worse cardiovascular outcomes in patients undergoing percutaneous coronary intervention. Recent clinical trials have not found any advantage in outcomes in patients who have their therapy adjusted by monitoring their platelet function. Newer agents, prasugrel, ticagrelor, and cangrelor, produce more rapid, complete, less variable effects on platelet function than clopidogrel. Prasugrel was found to improve outcomes compared with clopidogrel in patients with ACS undergoing percutaneous intervention. Ticagrelor is beneficial in all patients with ACS and reduces cardiovascular mortality compared with clopidogrel. Cangrelor improves outcomes in patients undergoing stenting. Recent studies to assess the role of platelet function monitoring of the effects of clopidogrel and modifying treatments have not been successful.

CONCLUSION

Recent clinical trials have indicated that newer antiplatelet agents have advantages over clopidogrel in the treatment of ACS. Platelet function testing gives us a guide to the timing, efficacy, and variability of therapy and can correlate with poor patient outcomes; however, the use of antiplatelet function testing to tailor therapy does not seem appropriate.

Cangrelor in patients undergoing cardiac surgery: the BRIDGE study

The benefit of long-term dual antiplatelet therapy (DAPT) in patients with acute coronary syndromes, drug-eluting stents and those at high risk for thromboembolic events has been well established in a number of well-designed randomized controlled studies. Current research in this area has focused on the development of novel antiplatelet agents for clinical use. The BRIDGE trial evaluated the use of cangrelor as a bridge to coronary artery bypass graft surgery in patients receiving extended DAPT. The BRIDGE trial results confirm the efficacy and safety of cangrelor in this population. This study is novel as it attempts to address the lapse in thienopyridine therapy required for many surgical and invasive procedures. The future of antiplatelet agents, particularly cangrelor, must also focus on bridging for high-risk patients undergoing noncoronary artery bypass graft surgical procedures. Overall, the BRIDGE trial represents a significant advance for patients appropriate for long-term DAPT.

Disclosure of individual pharmacogenomic results in research projects: when and what kind of information to return to research participants

In the growing field of genomics, the utility of returning certain research results to participants has become a highly debated issue. Existing guidelines are not explicit as to the kind of genomic information that should be returned to research participants. Moreover, very few current recommendations and articles in the literature address the return of pharmacogenomic results. Although genetics and pharmacogenomics have many similarities, the circumstances in which disclosure could have a benefit for the participants are different. This review aims to describe the conditions in which disclosure of pharmacogenomic results is appropriate.

Contrast media: are there differences in nephrotoxicity among contrast media?

Iodinated contrast agents are usually classified based upon their osmolality--high, low, and isosmolar. Iodinated contrast agents are also nephrotoxic in some but not all patients resulting in loss of glomerular filtration rate. Over the past 30 years, nephrotoxicity has been linked to osmolality although the precise mechanism underlying such a link has been elusive. Improvements in our understanding of the pathogenesis of nephrotoxicity and prospective randomized clinical trials have attempted to further explore the relationship between osmolality and nephrotoxicity. In this review, the basis for our current understanding that there are little if any differences in nephrotoxic potential between low and isosmolar contrast media will be detailed using data from clinical studies.

Comparison of bivalirudin versus heparin(s) during percutaneous coronary interventions in patients receiving prasugrel: a propensity-matched study

BACKGROUND

Several percutaneous coronary intervention (PCI) trials have established that the use of bivalirudin (BIV) is associated with improved patient outcomes and substantial hospital cost savings, relative to heparin (HEP)-based regimens±glycoprotein IIb/IIIa inhibitors (GPIs). Whether these benefits persist with the use of prasugrel, a new third-generation oral thienopyridine, has not been previously evaluated.

METHODS

Using the Premier hospital database, 6986 patients treated with prasugrel who underwent elective, urgent, or primary PCI between quarter 3, 2009 and quarter 4, 2010 from 166 US hospitals were identified. These patients received either BIV (n=3377) or HEP±GPI (n=3609) as procedural anticoagulation. Outcomes of interest included bleeding, transfusions, death, and hospital length of stay (LOS). To control for patient and hospital-level characteristics, propensity score-matching (PSM) analyses were performed.

RESULTS

Mortality, clinically apparent bleeding, clinically apparent bleeding requiring transfusion, any transfusions, and LOS were all lower in patients treated with BIV as compared with patients treated with HEP±GPI. After PSM, the rate of transfusion was significantly lower with BIV (odds ratio: 0.57, 95% confidence interval: 0.34-0.96), and the hospital LOS was significantly shorter in patients treated with BIV compared with those treated with HEP±GPI (0.9±2.0 vs 1.2±2.3 days, P<0.0001).

CONCLUSIONS

In patients undergoing PCI and treated with prasugrel, the use of BIV rather than HEP±GPI is associated with significantly lower transfusion rate and LOS. These results suggest that the previously documented safety and cost-effectiveness benefits of BIV remain applicable when prasugrel is used.

Comparative effectiveness of upstream glycoprotein IIb/IIIa inhibitors in patients with moderate- and high-risk acute coronary syndromes: an Acute Catheterization and Urgent Intervention Triage Strategy (ACUITY) substudy

BACKGROUND

Tirofiban and eptifibatide are both small-molecule, competitive glycoprotein IIb/IIIa receptor inhibitors (GPIs) that are guideline-supported for upstream therapy in acute coronary syndromes (ACS). This study sought to compare the efficacy and safety of tirofiban and eptifibatide in patients with ACS.

METHODS

Within the ACUITY trial, 4,323 patients with moderate- and high-risk ACS received upstream, adjunctive GPI (tirofiban or eptifibatide) in addition to an antithrombin. Primary outcomes included 30-day rates of composite major adverse cardiac events (MACE), major bleeding (not related to coronary artery bypass grafting), and composite net adverse clinical events (NACE). The outcomes were compared based on the upstream GPI administered.

RESULTS

There were significant differences in the baseline characteristics of patients treated with tirofiban vs eptifibatide, particularly related to country/region. In unadjusted analyses, treatment with upstream tirofiban vs eptifibatide was associated with similar rates of major bleeding (5.8% vs 6.5%, P = .39) and nonsignificantly lower rates of MACE (6.1% vs 7.6%, P = .06) and NACE (10.6% vs 12.6%, P = .06). After propensity-based multivariable adjustment, there were no significant differences between tirofiban and eptifibatide with respect to 30-day major bleeding, MACE, or NACE.

CONCLUSIONS

Among more than 4,000 patients with moderate- and high-risk ACS treated with upstream GPI as part of an early invasive management strategy, the use of tirofiban and eptifibatide resulted in similar clinical outcomes. These data suggest equivalence of these 2 agents for upstream use, while highlighting some of the difficulties of nonrandomized comparative effectiveness analyses, specifically the difficulty in addressing geographic differences in the use of nonrandomized treatments.

Managing the Complications of Mild Therapeutic Hypothermia in the Cardiac Arrest Patient

Mild therapeutic hypothermia (MTH) is used to lower the core body temperature of cardiac arrest (CA) patients to 32°C from 34°C to provide improved survival and neurologic outcomes after resuscitation from in-hospital or out-of-hospital CA. Despite the improved benefits of MTH, there are potentially unforeseen complications associated during management. Although the adverse effects are transient, the clinician should be aware of the associated complications when managing the patient receiving MTH. We aim to provide the medical community comprehensive information related to the potential complications of survivors of CA receiving MTH, as it is imperative for the clinician to understand the physiologic changes that take place in the patient receiving MTH and how to prepare for them and manage them if they do occur. We hope to provide information of how to manage these potential complications through both a review of the current literature and a reflection of our own experience.

A patient with HIV and tuberculosis with diminished clopidogrel response

Patients with HIV are at an increased risk for cardiovascular disease, both as a result of treatment with protease inhibitors and from the disease itself. The medication regimens of patients with HIV and cardiovascular comorbidities are complex and require careful assessment for potentially serious drug-drug interactions. We report a case of clopidogrel non-responsiveness in a patient with HIV, latent tuberculosis and cardiovascular disease with a history of myocardial infarction. To our knowledge, this is the first report of significant drug interactions between clopidogrel, isoniazid and ritonavir. This case underscores the importance of a detailed drug interaction screening in infectious disease patients taking complex medication regimens, including clopidogrel.

Cardiomyocyte injury assessed by a highly sensitive troponin assay and sudden cardiac death in the community: the Cardiovascular Health Study

OBJECTIVES

This study sought to determine the association between markers of cardiomyocyte injury in ambulatory subjects and sudden cardiac death (SCD).

BACKGROUND

The pathophysiology of SCD is complex but is believed to be associated with an abnormal cardiac substrate in most cases. The association between biomarkers of cardiomyocyte injury in ambulatory subjects and SCD has not been investigated.

METHODS

Levels of cardiac troponin T, a biomarker of cardiomyocyte injury, were measured by a highly sensitive assay (hsTnT) in 4,431 ambulatory participants in the Cardiovascular Health Study, a longitudinal community-based prospective cohort study. Serial measures were obtained in 3,089 subjects. All deaths, including SCD, were adjudicated by a central events committee.

RESULTS

Over a median follow-up of 13.1 years, 246 participants had SCD. Baseline levels of hsTnT were significantly associated with SCD (hazard ratio [HR] for +1 log(hsTnT): 2.04, 95% confidence interval [CI]: 1.78 to 2.34]. This association persisted in covariate-adjusted Cox analyses accounting for baseline risk factors (HR: 1.30, 95% CI: 1.05 to 1.62), as well as for incident heart failure and myocardial infarction (HR: 1.26, 95% CI: 1.01 to 1.57). The population was also categorized into 3 groups based on baseline hsTnT levels and SCD risk [fully adjusted HR: 1.89 vs. 1.55 vs. 1 (reference group) for hsTnT ≥12.10 vs. 5.01 to 12.09 vs. ≤ 5.00 pg/ml, respectively; p trend = 0.005]. On serial measurements, change in hsTnT levels was also associated with SCD risk (fully adjusted HR for +1 pg/ml per year increase from baseline: 1.03, 95% CI: 1.01 to 1.06).

CONCLUSIONS

The findings suggest an association between cardiomyocyte injury in ambulatory subjects and SCD risk beyond that of traditional risk factors.

The bleeding risk score as a mortality predictor in patients with acute coronary syndrome

BACKGROUND

It is well known that the occurrence of bleeding increases in-hospital mortality in patients with acute coronary syndromes (ACS), and there is a good correlation between bleeding risk scores and bleeding incidence. However, the role of bleeding risk score as mortality predictor is poorly studied.

OBJECTIVE

The main purpose of this paper was to analyze the role of bleeding risk score as in-hospital mortality predictor in a cohort of patients with ACS treated in a single cardiology tertiary center.

METHODS

Out of 1655 patients with ACS (547 with ST-elevation ACS and 1118 with non-ST-elevation ACS), we calculated the ACUITY/HORIZONS bleeding score prospectively in 249 patients and retrospectively in the remaining 1416. Mortality information and hemorrhagic complications were also obtained.

RESULTS

Among the mean age of 64.3 ± 12.6 years, the mean bleeding score was 18 ± 7.7. The correlation between bleeding and mortality was highly significant (p < 0.001, OR = 5.296), as well as the correlation between bleeding score and in-hospital bleeding (p < 0.001, OR = 1.058), and between bleeding score and in-hospital mortality (adjusted OR = 1.121, p < 0.001, area under the ROC curve 0.753, p < 0.001). The adjusted OR and area under the ROC curve for the population with ST-elevation ACS were, respectively, 1.046 (p = 0.046) and 0.686 ± 0.040 (p < 0.001); for non-ST-elevation ACS the figures were, respectively, 1.150 (p < 0.001) and 0.769 ± 0.036 (p < 0.001).

CONCLUSIONS

Bleeding risk score is a very useful and highly reliable predictor of in-hospital mortality in a wide range of patients with acute coronary syndromes, especially in those with unstable angina or non-ST-elevation acute myocardial infarction.

Tailored antiplatelet therapy and clinical adverse outcomes

OBJECTIVE

The clinical evidence regarding the influence of tailored antiplatelet strategy on adverse outcomes has been controversial. The aim of the study was to evaluate the significance of tailored antiplatelet therapy with respect to clinical adverse events in antiplatelet-resistant patients.

METHODS

Randomised studies that assess clinical relevance of personalised antiplatelet treatment in antiplatelet-resistant patients were identified through a literature search: PubMed, EMBASE, Web of Science and the Cochrane Library. The primary endpoint was the composite of death from any cause and stent thrombosis. All total clinical adverse events and bleeding complications were evaluated.

RESULTS

Data were combined across seven randomised studies comprising 12 048 subjects, of whom 3738 (31.0%) were found to be antiplatelet-resistant. Antiplatelet-resistant patients provided with tailored antiplatelet therapy showed less risk of death or stent thrombosis than those assigned conventional antiplatelet treatment (0.5% vs. 2.2%; OR (95% CI) 0.25 (0.13 to 0.49), p<0.0001). A significant benefit in terms of total adverse event risk reduction was observed during follow-up for tailored vs conventional antiplatelet therapy (5.5% vs. 10.0%; OR (95% CI) 0.40 (0.20 to 0.77), p=0.006). No statistical difference in bleeding complications was observed between these two groups (p=0.08).

CONCLUSIONS

In the study, personalised antiplatelet treatment for antiplatelet resistance was found to be associated with less occurrence of death or stent thrombosis and the less risk of total clinical adverse events than conventional treatment, without increasing the risk of bleeding complications.