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Kristian Kragholm, Laura Kristin Newby, Chiara Melloni Duke Clinical Research Institute, Duke University Medical Center, Durham, NC, USA Abstract: Each year, despite optimal use of recommended acute and secondary prevention therapies, 4%–5% of patients with acute coronary syndrome (ACS) experience relapse of ACS or other cardiovascular events including stroke, heart failure, or sudden cardiac death after the index ACS. The sudden atherosclerotic plaque rupture leading to an ACS event is often accompanied by inflammation, which is thought to be a key pathogenic pathway to these excess cardiovascular events. Losmapimod is a novel, oral p38 mitogen-activated protein kinase (MAPK) inhibitor that targets MAPKs activated in macrophages, myocardium, and endothelial cells that occur as a part of global coronary vascular inflammation following plaque rupture. This review aims to 1) discuss the pathophysiological pathways through which p38 MAPKs may play key roles in initiation and progression of inflammatory disease and how losmapimod is thought to counteract these p38 MAPKs, and 2) to describe the efficacy and safety data for losmapimod obtained from preclinical studies and randomized controlled trials that support the hypothesis that it has promise as a treatment for patients with ACS. Keywords: p38 MAPK, p38 MAPK inhibitor, losmapimod, safety, efficacy, outcomes

Background: The use of upstream small-molecule glycoprotein (GP) IIb/IIIa inhibitors in non-ST-segment elevation acute coronary syndromes (NSTE ACS) has been studied in multiple randomized clinical trials. We systematically reviewed the effect of upstream GP IIb/IIIa inhibitor use in NSTE ACS as reported in published clinical trials.Methods and Results: Randomized clinical trials of upstream small-molecule GP IIb/IIIa inhibitors in NSTE ACS were identified through a PubMed and EMBASE search and were included if they contained 30-day outcome data. Odds ratios were generated from the published data and pooled by means of random effects modeling. The primary outcome measures were 30-day death and 30-day death or myocardial infarction. Primary safety measures were major bleeding and transfusion during the index hospitalization. Twelve clinical trials were included, evaluating tirofiban, eptifibatide, and lamifiban. Of these, 7 evaluated upstream GP IIb/IIIa inhibitors versus placebo (n=24 031) and 5 evaluated a strategy of upstream GP IIb/IIIa inhibitors versus upstream placebo with later provisional use at the time of percutaneous coronary intervention (n=19 643). Overall, upstream GP IIb/IIIa inhibitor use was associated with an 11% reduction in 30-day death/myocardial infarction (odds ratio [OR], 0.89; 95% confidence interval [CI], 0.83 to 0.95) but no significant mortality effect (OR, 0.93; 95% CI, 0.83 to 1.05). The risk of major bleeding was 23% higher in patients treated with upstream GP IIb/IIIa inhibitors (OR, 1.23; 95% CI, 1.02 to 1.48). Results were similar when only trials comparing upstream GP IIb/IIIa inhibitors versus placebo were considered: 30-day death/myocardial infarction (OR, 0.88; 95% CI, 0.81 to 0.95); 30-day death (OR, 0.89; 95% CI, 0.76 to 1.03); and major bleeding (OR, 1.17; 95% CI, 0.88 to 1.54). Upstream versus selective use at percutaneous coronary intervention trended toward lower 30-day death/myocardial infarction (OR, 0.91; 95% CI, 0.82 to 1.01) but had no effect on mortality (OR, 1.00; 95% CI, 0.81 to 1.23) and increased major bleeding risk by 34% (OR, 1.34; 95% CI, 1.10 to 1.63).Conclusions: In NSTE ACS, treatment with upstream small-molecule GP IIb/IIIa inhibitors provides a significant but modest ischemic benefit when compared with initial placebo. Compared with delayed, selective use at percutaneous coronary intervention, early upstream use is associated with a trend toward fewer ischemic events. However, these modest benefits are associated with an increased risk of bleeding. [ABSTRACT FROM AUTHOR]

Background: Glycoprotein (GP) IIb/IIIa inhibitors can improve outcomes in patients with non-ST-segment elevation acute coronary syndromes but raise the risk of bleeding, particularly if dosed in excess. The impact of GP IIb/IIIa dosing feedback on safety and major bleeding is unknown.Methods: Glycoprotein IIb/IIIa dosing feedback was added to the CRUSADE quarterly site reports in the first quarter of 2006. We describe GP IIb/IIIa use and dosing among 25,641 patients with non-ST-segment elevation acute coronary syndromes from the fourth quarter of 2005 to the fourth quarter of 2006.Results: Eleven thousand eight hundred forty-six patients received GP IIb/IIIa inhibitors, including 4,031 women and 2,609 elderly patients (age, ≥75 years). Among GP IIb/IIIa-treated patients, unadjusted rates of excess GP IIb/IIIa dosing declined overall (26.4%-22.4%, Ptrend=.01) and among the elderly (65.6%-52.1%, Ptrend<.001). After adjustment, declines in excess dosing remained significant only for the elderly, although more than half of GP IIb/IIIa-treated elderly patients continued to receive excess dosing at the end of the study period (64.1%-51.3%, Ptrend<.001). There were concurrent declines in unadjusted major bleeding rates overall (9.6%-8.0%, Ptrend=.02), but declines among women (14.4%-11.5%, Ptrend=.08) and the elderly (17.1%-11.0%, Ptrend=.05) did not reach statistical significance. After adjustment for baseline characteristics and excess dosing, declines in major bleeding rates were no longer significant overall or for any subgroup.Conclusion: Within 9 months of initiating a safety feedback program, we observed early decreases in excess GP IIb/IIIa dosing among the elderly but minimal changes in excess dosing overall. Further work is needed to promote safe and effective medication use in vulnerable patients who are most at risk of harm. [ABSTRACT FROM AUTHOR]

Background: Because acute occlusion of coronary arteries supplying the inferolateral myocardium frequently eludes standard 12-lead electrocardiogram (ECG) diagnosis, these patients may present as non-ST-segment elevation acute coronary syndromes (NSTE-ACS). Methods: We examined culprit artery occlusion among 1,957 NSTE-ACS patients in the Platelet IIb/IIIa Antagonism for the Reduction of Acute Coronary Syndrome Events in a Global Organization Network trial who underwent diagnostic coronary angiography. We compared baseline characteristics, electrocardiographic findings, in-hospital treatment, and long-term outcomes between patients with and without occluded culprit arteries. Results: The culprit artery was occluded in 528 (27%) patients. Culprit lesions were more frequently identified in the inferolateral territory among patients with an occluded culprit artery (63%) compared with those with a nonoccluded artery (45%, P < .0001). Patients with an occluded culprit artery were younger, more often male, and more likely to have had a prior myocardial infarction. Despite similar in-hospital treatment, patients with an occluded culprit artery had larger infarcts (median peak creatine kinase-MB 4.3 vs 2.1 x upper limit of normal, P < .0001) and higher risk-adjusted 6-month mortality (hazard ratio 1.72, 95% CI 1.07-2.79). Conclusions: More than 25% of NSTE-ACS patients had an occluded culprit artery on angiography. These patients may represent ST-segment elevation myocardial infarction equivalents; thus, improved early risk stratification techniques would help more rapidly triage these high-risk patients to an early invasive management strategy. [ABSTRACT FROM AUTHOR]

Context: Effective medical care assumes delivery of evidence-based medicines to appropriate patients with doses comparable to those studied.Objective: To investigate dosing of unfractionated heparin (UFH), low-molecular-weight heparin (LMWH), and glycoprotein IIb/IIIa inhibitors, and the association between dosing and major outcomes.Design, Setting, and Participants: A prospective observational analysis in 387 US academic and nonacademic hospitals of 30,136 patients from the CRUSADE (Can Rapid Risk Stratification of Unstable Angina Patients Suppress Adverse Outcomes With Early Implementation of the American College of Cardiology/American Heart Association Guidelines) National Quality Improvement Initiative Registry who had non-ST-segment elevation acute coronary syndromes (NSTE ACS) with chest pain and either positive electrocardiograms or cardiac biomarkers between January 1 and September 30, 2004.Main Outcome Measures: Excessive dosing of UFH, LMWH, and glycoprotein IIb/IIIa inhibitors and major clinical outcomes, including bleeding, in-hospital mortality, and length of stay.Results: A total of 3354 patients (42%) with NSTE ACS who were administered antithrombotic agents received at least 1 initial dose outside the recommended range. An excess dose was administered to 2934 patients (32.8%) treated with UFH, 1378 (13.8%) treated with LMWH, and 2784 (26.8%) treated with glycoprotein IIb/IIIa inhibitors. Factors associated with excess dosing included older age, as well as female sex, renal insufficiency, low body weight, diabetes mellitus, and congestive heart failure. Relative to those patients not administered excess dosages, patients with excess dosages of UFH, LMWH, and glycoprotein IIb/IIIa inhibitors either tended toward or had higher risks for major bleeding (adjusted odds ratio [OR], 1.08; 95% confidence interval [CI], 0.94-1.26; OR, 1.39; 95% CI, 1.11-1.74; and OR, 1.36; 95% CI, 1.10-1.68; respectively). Bleeding increased relative to the degree of excess dose and to the number of agents administered in excess (6.6% [237/3590] if neither heparin nor glycoprotein IIb/IIIa excess vs 22.2% [93/419] if both excess). Mortality and length of stay were also higher among those patients administered excess dosing. We estimated that 15% (400/2766) of major bleeding in this population may be attributable to excess dosing.Conclusions: Patients with NSTE ACS treated in the community often receive excess doses of antithrombotic therapy. Dosing errors occur more often in vulnerable populations and predict an increased risk of major bleeding. [ABSTRACT FROM AUTHOR]

In the United States each year, >5.3 million patients present to emergency departments with chest discomfort and related symptoms. Ultimately, >1.4 million individuals are hospitalized for unstable angina and non-ST-segment elevation myocardial infarction. For emergency physicians and cardiologists alike, these patients represent an enormous challenge to accurately diagnose and appropriately treat. This update of the 2002 American College of Cardiology/American Heart Association Guidelines for the Management of Patients with Unstable Angina and Non-ST-Segment Elevation Myocardial Infarction (UA/NSTEMI) provides an evidence-based approach to the diagnosis and treatment of these patients in the emergency department, in-hospital, and after hospital discharge. Despite publication of the guidelines several years ago, many patients with UA/NSTEMI still do not receive guidelines-indicated therapy. [ABSTRACT FROM AUTHOR]

STUDY OBJECTIVE: Previous studies in clinical trial populations have demonstrated that patients presenting with positive troponin levels have a higher risk of mortality than patients with later positive troponin levels, but the influence of the timing of troponin elevation has not been previously characterized. We evaluate the impact of the timing of troponin elevation on clinical outcomes and adherence to the American College of Cardiology/American Heart Association acute care guidelines for patients with non-ST-segment elevation acute coronary syndromes. METHODS: We examined inhospital outcomes and use of acute (<24 hours) medications and invasive cardiac procedures in 23,184 high-risk patients with non-ST-segment elevation acute coronary syndromes (positive cardiac markers or ischemic ST-segment changes) during 2001 to 2002 from 396 US hospitals participating in the Can Rapid Risk Stratification of Unstable Angina Patients Suppress ADverse Outcomes with Early Implementation of the American College of Cardiology/American Heart Association Guidelines (CRUSADE) Initiative. Baseline and peak troponin values were recorded and were designated as positive if above the cutoff value used at each institution to designate definite myocardial necrosis. RESULTS: In the study cohort, 53.2% of patients presented with baseline positive troponin levels, 30.6% had baseline negative/later positive troponin levels, and 16.2% had negative troponin levels during the entire hospitalization. Patients with baseline positive troponin levels had a higher risk of inhospital mortality than patients with baseline negative/later positive troponin levels (6.5% versus 4.1%) and were less likely to undergo early cardiac catheterization or percutaneous coronary intervention. The use of acute aspirin (in approximately 91% of patients), heparin (85%), and beta-blockers (78%) was similar in patients with baseline-positive versus later-positive troponin levels. CONCLUSION: These findings demonstrate that evidence-based therapies and interventions for non-ST-segment elevation acute coronary syndromes are underused in patients with elevated troponin levels, but baseline troponin elevations, which are associated with a higher risk of inhospital mortality, do not stimulate more aggressive care. [ABSTRACT FROM AUTHOR]

We studied stent thrombosis in 4,607 patients with acute coronary syndromes who received a coronary stent as part of routine care during 2 trials of aspirin versus sibrafiban for secondary prevention. In these patients, stent thrombosis occurred more often than in previous patients who underwent elective percutaneous coronary intervention. These patients and their outcomes may be more representative of patients with typical acute coronary syndromes undergoing stenting in clinical practice. [ABSTRACT FROM AUTHOR]

Objectives: Our primary objective was to examine the prognostic relationship between baseline quantitative ST-segment depression (ST) and cardiac troponin T (cTnT) elevation. The secondary objectives were to: 1) examine whether ST provided additional insight into therapeutic efficacy of glycoprotein IIb/IIIa therapy similar to that demonstrated by cTnT; and 2) explore whether the time to evaluation impacted on each marker's relative prognostic utility.Background: The relationship between the baseline electrocardiogram (ECG) and cTnT measurements in risk-stratifying patients presenting with acute coronary syndromes (ACS) has not been evaluated comprehensively.Methods: The study population consisted of 959 patients enrolled in the cTnT substudy of the Platelet IIb/IIIa Antagonism for the Reduction of Acute coronary syndrome events in a Global Organization Network (PARAGON)-B trial. Patients were classified as having no ST (n = 387), 1 mm ST (n = 433), and ST > or =2 mm (n = 139). Forty-percent (n = 381) were classified as cTnT-positive based on a definition of > or =0.1 ng/ml.Results: Six-month death/(re)myocardial infarction rates were 8.4% among cTnT-negative patients with no ST and 26.8% among cTnT-positive patients with ST > or =2 mm. On ECGs done after 6 h of symptom onset, ST > or =2 mm was associated with higher risk compared to its presence on ECGs done earlier (odds ratio [OR] 7.3 vs. 2.1). In contrast, the presence of elevated cTnT within 6 h of symptom was associated with a higher risk of adverse events compared with elevations after 6 h (OR 2.4 vs. 1.5).Conclusions: Quantitative ST and cTnT status are complementary in assessing risk among ACS patients and both should be employed to determine prognosis and assist in medical decision making. [ABSTRACT FROM AUTHOR]

We evaluated cardiac troponin T (cTnT) and creatine kinase-MB (CK-MB) for risk stratification of chest pain unit (CPU) patients. We studied 383 consecutive patients with chest pain assigned to our CPU by emergency department physicians. At baseline all had normal or nondiagnostic electrocardiograms, no high-risk clinical features, and negative CK/CK-MB. CK-MB and electrocardiograms were taken at 0, 4, 8, and 12 hours and cTnT at 0, 4, and 8 hours. Eight patients (2.1%) were CK-MB positive and 39 (10.2%) were cTnT positive, including all but 1 CK-MB-positive patient. All marker-positive patients were detected by 8 hours. Seven cTnT-positive patients and 1 cTnT-negative patient had myocardial infarction (p <0.0001). cTnT-positive patients were older, less likely to be women or smokers, and more often had diabetes mellitus or known coronary disease (CAD). Seventy-one percent of patients underwent diagnostic testing. cTnT-positive patients more often underwent angiography (46% vs 20%) and underwent stress testing less often (28% vs 57%) than cTnT-negative patients. When performed, their stress tests were more often positive (46% vs 14%) and they more often had angiographically significant lesions (89% vs 49%) and multivessel disease (67% vs 29%). There were no short-term deaths. Long-term mortality was higher in cTnT-positive patients (27% vs 7%, p <0.0001). Thus, cTnT identified more CPU patients with myocardial necrosis and multivessel CAD than CK-MB and a population with high long-term mortality risk. Routine use of cTnT in CPUs could facilitate risk stratification and management. [ABSTRACT FROM AUTHOR]