Critical Assessment of the Management of Unstable Angina in a Specialized Cardiology Emergency Room. / Avaliação Crítica do Manejo da Angina Instável em Pronto-Socorro Terciário de Cardiologia.

BACKGROUND: The management of unstable angina (UA) presents a challenge due to its subjective diagnosis and limited representation in randomized clinical trials that inform current practices. OBJECTIVES: This study aims to identify key factors associated with the indication for invasive versus non-invasive stratification in this population and to evaluate factors associated with stratification test results. METHODS: This retrospective cohort study included patients hospitalized with UA over a consecutive 20-month period. To assess factors associated with stratification strategies, patients were divided into invasive stratification (coronary angiography) and non-invasive stratification (other methods) groups. For the analysis of factors related to changes in stratification tests, patients were categorized into groups with or without obstructive coronary artery disease (CAD) or ischemia, as per the results of the requested tests. Comparisons between groups and multiple logistic regression analyses were performed, with statistical significance set at a 5% level. RESULTS: A total of 729 patients were included, with a median age of 63 years and a predominance of males (64.6%). Factors associated with invasive stratification included smoking (p = 0.001); type of chest pain (p < 0.001); "crescendo" pain (p = 0.006); TIMI score (p = 0.006); HEART score (p = 0.011). In multivariate analysis, current smokers (OR 2.23, 95% CI 1.13-4.8), former smokers (OR 2.19, 95% CI 1.39-3.53), and type A chest pain (OR 3.39, 95% CI 1.93-6.66) were independently associated. Factors associated with obstructive CAD or ischemia included length of hospital stay (p < 0.001); male gender (p = 0.032); effort-induced pain (p = 0.037); Diamond-Forrester score (p = 0.026); TIMI score (p = 0.001). In multivariate analysis, only chest pain (type B chest pain: OR 0.6, 95% CI 0.38-0.93, p = 0.026) and previous CAD (OR 1.42, 95% CI 1.01-2.0, p = 0.048) were independently associated. CONCLUSION: The type of chest pain plays a crucial role not only in the diagnosis of UA but also in determining the appropriate treatment. Our results highlight the importance of incorporating pain characteristics into prognostic scores endorsed by guidelines to optimize UA management.

FUNDAMENTO: O manejo da angina instável (AI) é um desafio devido ao seu diagnóstico subjetivo e à sua escassa representação em ensaios clínicos randomizados que determinem as práticas atuais. OBJETIVOS: O objetivo deste estudo é identificar os principais fatores associados à indicação de estratificação invasiva ou não nessa população e avaliar os fatores associados às alterações nos exames de estratificação. MÉTODOS: Coorte retrospectiva de pacientes internados por AI, em um período de 20 meses consecutivos. Para avaliar os fatores associados à estratégia de estratificação, os pacientes foram divididos em estratificação invasiva (cinecoronariografia) e não invasiva (demais métodos). Para análise de fatores relacionados às alterações nos exames de estratificação, os pacientes foram divididos em grupos com ou sem doença arterial coronariana (DAC) obstrutiva ou isquemia, conforme resultados dos exames solicitados. Foram realizadas comparações entre grupos e análise de regressão logística múltipla, com significância estatística definida em um nível de 5%. RESULTADOS: 729 pacientes foram incluídos, com mediana de idade de 63 anos e predomínio do sexo masculino (64,6%). Estiveram associados à estratificação invasiva: tabagismo (p = 0,001); tipo de dor torácica (p < 0,001); dor "em crescendo" (p = 0,006); escore TIMI (p = 0,006); escore HEART (p = 0,011). Na análise multivariada, tabagistas (OR 2,23, IC 95% 1,13-4,8), ex-tabagistas (OR 2,19, IC 1,39-3,53) e dor torácica tipo A (OR 3,39, IC 95% 1,93-6,66) estiveram associados de forma independente. Estiveram associados à DAC obstrutiva ou isquemia: tempo de internação hospitalar (p < 0,001); sexo masculino (p = 0,032); dor desencadeada por esforço (p = 0,037); Diamond-Forrester (p = 0,026); escore TIMI (p = 0,001). Na análise multivariada, apenas dor torácica (dor torácica tipo B: OR 0,6, IC 95% 0,38-0,93, p = 0,026) e DAC prévia (OR 1,42, IC 95% 1,01-2,0, p = 0,048) estiveram associadas de maneira independente. CONCLUSÕES: O tipo de dor torácica desempenha um papel crucial não apenas no diagnóstico da AI, mas também na definição do tratamento adequado. Nossos resultados destacam a importância de incorporar características da dor aos escores prognósticos endossados pelas diretrizes, para otimização do manejo da AI.

Interleukin-33/sST2: Dynamic assessment in patients with acute coronary syndrome.

PURPOSE: Interleukin (IL)-33 and its soluble receptor ST2 (sST2) play a crucial role in the immune response. sST2 has been approved by the Food and Drug Administration as a prognostic biomarker of mortality in chronic heart failure patients, however, the role of IL-33 and sST2 in atherosclerotic cardiovascular disease remains unclear. The aim of this study was to measure serum level of IL-33 and sST2 of patients at the onset of acute coronary syndrome (ACS) and 3 months after primary percutaneous revascularization. PATIENTS AND METHODS: Forty patients were divided into ST segment elevation myocardial infarction (STEMI) group, non-ST segment elevation myocardial infarction (NSTEMI) and unstable angina (UA) group. IL-33 and sST2 level were measured with ELISA. Additionally, IL-33 expression in peripheral blood mononuclear cells (PBMCs), was evaluated. RESULTS: All ACS patients had a significantly lower level of sST2 3 months after ACS as compared to the baseline (p â€‹< â€‹0.039). The STEMI patients had higher serum levels of IL-33 at the moment of ACS as compared to 3 months after the event, with an average decrease of 17.87 â€‹pg/ml (p â€‹< â€‹0.007). Conversely, sST2 serum levels were still high after 3 months following an ACS in STEMI patients. ROC curve demonstrated that increased IL-33 serum level could be STEMI predictor. CONCLUSIONS: The assessment of the baseline and dynamics of changes in IL-33 and sST2 concentrations in patients with ACS may be important for the diagnostic process and may help in understanding of how the immune mechanisms work at the moment of an ACS event.

Acute coronary syndrome: role of the nurse in patient assessment and management.

Coronary heart disease is a leading cause of mortality, morbidity and hospitalisation in the UK and worldwide. Acute coronary syndrome (ACS) is a serious manifestation of coronary heart disease. ACS encompasses several conditions that represent acute injury or damage to the myocardium, including ST-elevation myocardial infarction (STEMI), unstable angina and non-ST elevation myocardial infarction (NSTEMI). Management may differ depending on the diagnosis, so prompt and accurate assessment is crucial to establish the patient's condition and ensure timely initiation of the appropriate treatment. This article explains how ACS develops and what characterises its different types. It also outlines the assessment and management of patients with ACS, and explains the nurse's role in these processes.

Early invasive versus non-invasive assessment in patients with suspected non-ST-elevation acute coronary syndrome.

Non-ST-elevation acute coronary syndrome (NSTE-ACS) comprises a broad spectrum of disease ranging from unstable angina to myocardial infarction. International guidelines recommend a routine invasive strategy for managing patients with NSTE-ACS at high to very high-risk, supported by evidence of improved composite ischaemic outcomes as compared with a selective invasive strategy. However, accurate diagnosis of NSTE-ACS in the acute setting is challenging due to the spectrum of non-coronary disease that can manifest with similar symptoms. Heterogeneous clinical presentations and limited uptake of risk prediction tools can confound physician decision-making regarding the use and timing of invasive coronary angiography (ICA). Large proportions of patients with suspected NSTE-ACS do not require revascularisation but may unnecessarily undergo ICA with its attendant risks and associated costs. Advances in coronary CT angiography and cardiac MRI have prompted evaluation of whether non-invasive strategies may improve patient selection, or whether tailored approaches are better suited to specific subgroups. Future directions include (1) better understanding of risk stratification as a guide to investigation and therapy in suspected NSTE-ACS, (2) randomised clinical trials of non-invasive imaging versus standard of care approaches prior to ICA and (3) defining the optimal timing of very early ICA in high-risk NSTE-ACS.

Incidence and Outcomes of Acute Coronary Syndrome After Transcatheter Aortic Valve Replacement.

OBJECTIVES: This study sought to address a knowledge gap by examining the incidence, timing, and predictors of acute coronary syndrome (ACS) after transcatheter aortic valve replacement (TAVR) in Medicare beneficiaries. BACKGROUND: Evidence about incidence and outcomes of ACS after TAVR is scarce. METHODS: We identified Medicare patients who underwent TAVR from 2012 to 2017 and were admitted with ACS during follow-up. We compared outcomes based on the type of ACS: ST-segment elevation myocardial infarction (STEMI), non-STEMI (NSTEMI), and unstable angina. In patients with non-ST-segment elevation ACS, we compared outcomes based on the treatment strategy (invasive vs. conservative) using inverse probability weighting analysis. RESULTS: Out of 142,845 patients with TAVR, 6,741 patients (4.7%) were admitted with ACS after a median time of 297 days (interquartile range: 85 to 662 days), with 48% of admissions occurring within 6 months. The most common presentation was NSTEMI. Predictors of ACS were history of coronary artery disease, prior revascularization, diabetes, valve-in-TAVR, and acute kidney injury. STEMI was associated with higher 30-day and 1-year mortality compared with NSTEMI (31.4% vs. 15.5% and 51.2% vs. 41.3%, respectively; p < 0.01). Overall, 30.3% of patients with non-ST-segment elevation ACS were treated with invasive approach. On inverse probability weighting analysis, invasive approach was associated with lower adjusted long-term mortality (adjusted hazard ratio: 0.69; 95% confidence interval: 0.66 to 0.73; p < 0.01) and higher risk of repeat revascularization (adjusted hazard ratio: 1.29; 95% confidence interval: 1.16 to 1.43; p < 0.001). CONCLUSIONS: After TAVR, ACS is infrequent (<5%), and the most common presentation is NSTEMI. Occurrence of STEMI after TAVR is associated with a high mortality with nearly one-third of patients dying within 30 days. Optimization of care is needed for post-TAVR ACS patients and if feasible, invasive approach should be considered in these high-risk patients.

Pre-hospital risk assessment in suspected non-ST-elevation acute coronary syndrome: A prospective observational study.

BACKGROUND: Pre-hospital risk stratification of non-ST-elevation acute coronary syndrome (NSTE-ACS) by the complete HEART score has not yet been assessed. We investigated whether pre-hospital risk stratification of patients with suspected NSTE-ACS using the HEART score is accurate in predicting major adverse cardiac events (MACE). METHODS: This is a prospective observational study, including 700 patients with suspected NSTE-ACS. Risk stratification was performed by ambulance paramedics, using the HEART score; low risk was defined as HEART score ⩽ 3. Primary endpoint was occurrence of MACE within 45 days after inclusion. Secondary endpoint was myocardial infarction or death. RESULTS: A total of 172 patients (24.6%) were stratified as low risk and 528 patients (75.4%) as intermediate to high risk. Mean age was 53.9 years in the low risk group and 66.7 years in the intermediate to high risk group (p<0.001), 50% were male in the low risk group versus 60% in the intermediate to high risk group (p=0.026). MACE occurred in five patients in the low risk group (2.9%) and in 111 (21.0%) patients at intermediate or high risk (p<0.001). There were no deaths in the low risk group and the occurrence of acute myocardial infarction in this group was 1.2%. In the high risk group six patients died (1.1%) and 76 patients had myocardial infarction (14.4%). CONCLUSIONS: In suspected NSTE-ACS, pre-hospital risk stratification by ambulance paramedics, including troponin measurement, is accurate in differentiating between low and intermediate to high risk. Future studies should investigate whether transportation of low risk patients to a hospital can be avoided, and whether high risk patients benefit from immediate transfer to a hospital with early coronary angiography possibilities.

The pattern of risk-factor profile in Egyptian patients with acute coronary syndrome: phase II of the Egyptian cross-sectional CardioRisk project.

BACKGROUND: Egypt is the most populous country in the Middle East and North Africa and has more than 15% of the cardiovascular deaths in the region, but little is known about the prevalence of traditional risk factors and treatment strategies in acute coronary syndrome (ACS) patients across Egypt. METHODS: From November 2015 to August 2017, data were collected from 1 681 patients with ACS in 30 coronary care centres, covering 11 governorates across Egypt, spanning the Mediterranean coast, Nile Delta and Upper Egypt, with a focus on risk factors and management strategies. RESULTS: Women constituted 25% of the patients. Premature ACS was common, with 43% of men aged less than 55 years, and 67% of women under 65 years. Most men had ST-elevation myocardial infarction (STEMI) (49%), while a larger percentage of women had unstable angina and non-ST-elevation myocardial infarction (NSTEMI) (32% each; p < 0.001). Central obesity was present in 80% of men and 89% of women, with 32% of men and women having atherogenic dyslipidaemia. Current smoking was reported by 62% of men and by 72% of men under 55 years. A larger proportion of women had type 2 diabetes (53 vs 34% of men), hypertension (69 vs 49%), dyslipidaemia, and obesity (71 vs 41%) (p < 0.001 for all). There were no gender differences in most diagnostic and therapeutic procedures, but among STEMI patients, 51% of men underwent primary percutaneous coronary intervention compared to 46% of women (p = 0.064). CONCLUSIONS: Central obesity and smoking are extremely prevalent in Egypt, contributing to an increased burden of premature ACS, which warrants tailored prevention strategies. The recognised tendency worldwide to treat men more aggressively was less pronounced than expected.

Correlação entre a complexidade das lesões coronarianas e os níveis de Troponina ultrassensível em pacientes com Síndrome Coronariana Aguda / Correlation between the complexity of coronary lesions and high-sensitivity Troponin levels in patients with Acute Coronary Syndrome

Fundamento: As doenças cardiovasculares são a principal causa de morte no Brasil. Marcadores bioquímicos possuem importância diagnóstica e prognóstica nas síndromes coronarianas agudas (SCAs), sendo a troponina o biomarcador preferido. Estudos já demonstram relação positiva entre elevação da troponina ultrassensível (TnUs) e prognóstico. Entretanto, poucos relacionam seus níveis com a complexidade das lesões coronárias. Objetivos: Comparar níveis de TnUs com a complexidade das lesões coronarianas pelo escore SYNTAX e relacionar os escores TIMI e GRACE com os níveis desse biomarcador em pacientes com SCA. Métodos: Estudo retrospectivo, transversal com 174 indivíduos com SCA. A correlação entre as variáveis foi avaliada pelo teste de correlação linear não paramétrico de Spearman e a análise estatística realizada pelo programa SPSS, com nível de significância de 5%. Resultados: A média de idade foi 63 anos, predominando o sexo feminino (52,9%). A maioria dos pacientes era hipertensa, não diabética e não tabagista. Dos pacientes avaliados, 19,0% apresentaram IAM com SST, 43,1% IAM sem SST e 36,8% angina instável. A maioria encontrava-se em Killip 1 (82,8%). A mediana de TnUs foi de 67pg/ml. As medianas dos escores de risco foram de 3, 121 e 3 pontos nas escalas TIMI, GRACE e SYNTAX, respectivamente. Houve correlação da taxa de TnUs com os escores SYNTAX (p < 0,001, r = 0,440), TIMI (p < 0,001, r = 0,267) e GRACE (p = 0,001, r = 0,261). Conclusão: Encontrada correlação linear positiva entre os níveis de TnUs e complexidade das lesões coronarianas, assim como entre esse biomarcador e os escores clínicos TIMI e GRACE

Background: Cardiovascular diseases are the leading cause of death in Brazil. Biochemical markers have diagnostic and prognostic importance in acute coronary syndromes (ACSs), with troponin as the preferred biomarker. Studies have already demonstrated a positive relationship between increased levels of high-sensitivity troponin (hsTn) and prognosis. However, few studies have correlated hsTn levels with the complexity of coronary lesions. Objectives: To compare hsTn levels with the complexity of coronary lesions according to the SYNTAX score, and to correlate the levels of this biomarker with the TIMI and GRACE scores in patients with ACS. Methods: Retrospective, cross-sectional study with 174 patients with ACS. The correlation between variables was assessed by the nonparametric Spearman's rank correlation, and statistical analysis was performed by the SPSS program, with a significance level of 5%. Results: Mean age was 63 years, and most patients were women (52.9%), hypertensive, non-diabetic and non-smokers. Nineteen percent of the patients had STEMI, 43.1% NSTEMI, and 36.8% unstable angina. Most were in Killip 1 (82.8%). Median hsTn was 67 pg/mL. Median risk scores were 3, 121 and 3 in the TIMI, GRACE and SYNTAX scores, respectively. There was a correlation of hsTn with SYNTAX (p <0.001, r = 0.440), TIMI (p < 0.001, r = 0.267) and GRACE (p = 0.001, r = 0.261) scores. Conclusion: A positive linear correlation was found of hsTn levels with the complexity of coronary lesions, and with the TIMI and GRACE

Social inequality and barriers to cardiac rehabilitation in the rehab-North register.

AIM: Barriers to participation in cardiac rehabilitation (CR) may occur at three levels of the referral process (lack of information, declining to participate, and referral to appropriate CR programme). The aim is to analyse the impact of socioeconomic status on barriers to CR and investigate whether such barriers influenced the choice of referral. METHODS: The Rehab-North Register, a cross-sectional study, enrolled 5455 patients hospitalised at Aalborg University Hospital with myocardial infarction (MI) during 2011-2014. Patients hospitalised with ST-elevated MI and complicated non-ST-elevated MI were to be sent to specialized CR, whereas patients with uncomplicated non-ST-elevated MI and unstable angina pectoris were to be sent to community-based CR. Detailed selected socioeconomic information was gathered from statistical registries in Statistics Denmark. Data was assessed using logistic regression. RESULTS: Patients being retired, low educated, and/or with an annual gross income <27.000 Euro/yr were significantly less informed about cardiac rehabilitation programmes. Patients being older than 70 years, retired, low educated and/or with an annual gross income <27.000 Euro were significantly less willing to participate in CR. Further, this patient population were to a higher extent referred to community-based CR. CONCLUSION: Patients with low socioeconomic status received less information about and were less willing to participate in cardiac rehabilitation. The same patient population was to a higher extent referred to community-based CR. Knowledge about barriers at different levels and the impact of social inequality may help in tailoring a better approach in the referral process to CR.

Use of a high-sensitivity troponin T assay in the assessment and disposition of patients attending a tertiary Australian emergency department: a cross-sectional pilot study.

OBJECTIVE: We examined the disposition and outcomes of patients presenting to the ED with symptoms suggestive of acute coronary syndrome undergoing measurement of troponin T using a highly sensitive assay. METHODS: Troponin T (TnT) was measured in 204 consecutive patients (mean age = 65 [±18] years, 55% men) presenting to the ED with symptoms suggestive of acute coronary syndrome. RESULTS: Ninety-four patients predominantly had chest pain, 34 had dyspnoea and the remainder had various symptoms. Overall, 96 patients had TnT >14 ng/L (upper reference limit), of whom 31 were admitted to the cardiology service (26 had final cardiac diagnosis [five ST-elevation MI, 10 non-ST-elevation MI, one unstable angina and 10 other cardiac]). Among these 96 patients, 41 had chronic kidney disease, 17 had heart failure and seven had sepsis. At 30 days, death rates among patients who had TnT >14 ng/L with non-cardiac diagnoses and in patients who had TnT >14 ng/L with a cardiac diagnosis were 6.6% and 2.9% (P = 0.652); no death and/or MI occurred in patients with normal TnT levels. At late follow up (median 6.8 months) that was obtained in 189 (93% of 204) patients, four had MI and 14 died (three cardiac deaths). CONCLUSIONS: Despite high-sensitivity TnT assay having a high sensitivity and specificity for myocardial necrosis, the majority of unselected consecutive patients attending ED in whom TnT levels were elevated did not have an acute coronary syndrome. Our pilot study suggests that a larger study is needed to provide evidence to modify management algorithms.

Differences in short-term versus long-term outcomes of older black versus white patients with myocardial infarction: findings from the Can Rapid Risk Stratification of Unstable Angina Patients Suppress Adverse Outcomes with Early Implementation of American College of Cardiology/American Heart Association Guidelines (CRUSADE).

BACKGROUND: Blacks are less likely than whites to receive coronary revascularization and evidence-based therapies after acute myocardial infarction, yet the impact of these differences on long-term outcomes is unknown. METHODS AND RESULTS: We linked Can Rapid Risk Stratification of Unstable Angina Patients Suppress Adverse Outcomes With Early Implementation of American College of Cardiology/American Heart Association Guidelines (CRUSADE) registry data to national Medicare claims, creating a longitudinal record of care and outcomes among 40 500 patients with non-ST-segment-elevation myocardial infarction treated at 446 hospitals to examine mortality and readmission rates (mean follow-up, 2.4 years) among black and white patients. Relative to whites (n=37 384), blacks (n=3116) were more often younger and female; more often had diabetes mellitus and renal failure; and received less aggressive interventions, including cardiac catheterization (60.7% versus 54.0%; P<0.001), percutaneous coronary intervention (32.1% versus 23.8%; P<0.001), and coronary bypass surgery (9.2% versus 5.7%; P<0.001). Although blacks had lower 30-day mortality (9.1% versus 9.9%; adjusted hazard ratio, 0.80; 95% confidence interval, 0.71-0.92), they had higher observed mortality at 1 year (27.9% versus 24.5%; P<0.001), although this was not significant after adjustment on long-term follow-up (hazard ratio, 1.00; 95% confidence interval, 0.94-1.07). Black patients also had higher 30-day (23.6% versus 20.0%; P<0.001) and 1-year (62.0% versus 54.6%; P<0.001) all-cause readmission, but these differences were no longer significant after risk adjustment on 30-day (hazard ratio, 1.02; 95% confidence interval, 0.92-1.13) and long-term (hazard ratio, 1.05; 95% confidence interval, 1.00-1.11) follow-up. CONCLUSIONS: Although older blacks with an acute myocardial infarction had lower initial mortality rates than whites, this early survival advantage did not persist during long-term follow-up. The reasons for this are multifactorial but may include differences in comorbidities and postdischarge care.

Assessment of microRNAs in patients with unstable angina pectoris.

AIMS: While cardiac troponin measurements have significantly improved the early diagnosis of myocardial infarction, the timely biomarker-based diagnosis of unstable angina pectoris (UAP) remains a major unmet clinical challenge. The aim of this study was to assess levels of circulating microRNAs (miRNAs) as possible novel biomarkers in patients with UAP. METHODS AND RESULTS: A three-phase approach was conducted, comprising (i) profiling of miRNAs in patients with UAP and controls groups; (ii) replication of significant miRNAs in an independent patient cohort, (iii) validation of a multi-miRNAs panel in a third cohort. Out of 25 miRNAs selected for replication, 8 miRNAs remained significantly associated with UAP. In a validation phase, a miRNA panel including miR-132, miR-150, and miR-186 showed the highest discriminatory power [area under the receiver-operating-characteristic curve (AUC): 0.91; CI: 0.84-0.98]. CONCLUSION: Using a profiling-replication-validation model, we identified eight miRNAs, which may facilitate the diagnosis of UAP.

Prognostic value of heart rate turbulence for risk assessment in patients with unstable angina and non-ST elevation myocardial infarction.

BACKGROUND: We sought to examine the prognostic value of heart rate turbulence derived from electrocardiographic recordings initiated in the emergency department for patients with non-ST elevation myocardial infarction (NSTEMI) or unstable angina. METHODS: Twenty-four-hour Holter recordings were started in patients with cardiac symptoms approximately 45 minutes after arrival in the emergency department. Patients subsequently diagnosed with NSTEMI or unstable angina who had recordings with ≥18 hours of sinus rhythm and sufficient data to compute Thrombolysis In Myocardial Infarction (TIMI) risk scores were chosen for analysis (n = 166). Endpoints were emergent re-entry to the cardiac emergency department and/or death at 30 days and one year. RESULTS: In Cox regression models, heart rate turbulence and TIMI risk scores together were significant predictors of 30-day (model chi square 13.200, P = 0.001, C-statistic 0.725) and one-year (model chi square 31.160, P < 0.001, C-statistic 0.695) endpoints, outperforming either measure alone. CONCLUSION: Measurement of heart rate turbulence, initiated upon arrival at the emergency department, may provide additional incremental value in the risk assessment for patients with NSTEMI or unstable angina.

Classification of myocardial infarction and unstable angina: a re-assessment.

True or impending myocardial injury is being defined as an acute coronary syndrome (ACS), and includes ST-segment elevation MI, non-ST-segment elevation MI, and unstable angina. According to the revised MI definitions, patients with ischemic symptoms but with only a minor rise and fall in any biomarker are now being classified as having true myocardial injury. Against this background, this paper re-examines the position of "unstable angina" within the ACS context. It now must be acknowledged that the most recent definition of unstable angina, from 2000, which divided patients with unstable angina in those who were troponin-positive and those that remained troponin-negative, overlaps with the current MI definition. The seminal 1989 clinical definition of unstable angina thus remains the most appropriate description of that ACS entity. This "paradigm shift" has significant bearing on both the numbers of patients with non-ST-segment elevation MI, as well as on their prognosis. The same is true for patients now being diagnosed as having "unstable angina." To a large extent, future cardiovascular risk is determined by clinical parameters, and their proper assessment thus remains paramount. Elevated age, previous MI, diabetes and/or renal dysfunction and, in particular, the presence of recent onset of symptoms (Braunwald category IIIB) with concomitant ECG changes should identify those at high risk. Patients with such characteristics should benefit from thorough medical management, including extensive platelet inhibition in most and coronary revascularization in many.

Insignificant role of the N-terminal cobalt-binding site of albumin in the assessment of acute coronary syndrome: discrepancy between the albumin cobalt-binding assay and N-terminal-targeted immunoassay.

The aim of this study was to evaluate whether the N-terminus of human serum albumin (HSA) has a role in the cobalt binding detected using albumin cobalt-binding (ACB) assay. We compared the results obtained using an enzyme-linked immunosorbent assay (ELISA) for N-terminal-modified HSA with those of a conventional ACB assay in two groups: acute coronary syndrome (n = 43) and non-ischemic chest pain (n = 39). ACB and cardiac troponin-I levels were higher in the acute coronary syndrome group. No significant correlation between ACB assay and ELISA results was observed in either of the two patient groups. In acute chest pain patients, the N-terminal site of HSA has a negligible or limited role in cobalt binding in the ACB assay.

Effectiveness of nuclear scan strategy in low-risk chest pain patients: novel insights from the real world.

AIM: The aim this study is to update the diagnostic implementation of a costly scan strategy in chest pain (CP) patients. METHODS: Low-risk CP patients with a negative first-line work-up including clinical evaluation, serial ECGs, and serial troponins underwent stress myocardial perfusion imaging (MPI). Those with perfusion defects underwent angiography, whereas the remaining patients were discharged and followed up. The endpoint was coronary stenosis greater than or equal to 50% at angiography or cardiovascular death, myocardial infarction, unstable angina, and revascularization at follow-up. RESULTS: Out of 1089 patients enrolled, 966 underwent exercise-MPI and 123 pharmacological-MPI (91 adenosine-MPI and 32 dipyridamole-MPI). Areas under the receiver-operating characteristic curve of exercise-MPI and pharmacological-MPI were comparable. The sensitivity and negative predictive value were significantly higher in patients subjected to exercise-MPI or pharmacological-MPI versus exercise-ECG or pharmacological-ECG (P < 0.001). The presence of basal nonischemic ECG or basal nonischemic echocardiography alterations was an independent predictor of coronary events; in these patients, the positive predictive value of the nuclear scan was significantly higher compared with the remaining patients (72 vs. 43%, P < 0.0001). The predictive values in patients subjected to adenosine-MPI or dipyridamole-MPI were eventually comparable. CONCLUSION: In low-risk CP patients, a costly stress nuclear scan strategy added incremental prognostic value over stress-ECG and was appropriate especially in patients presenting basal nonischemic ECG or basal nonischemic echocardiography alterations.

Delays in presentation with acute coronary syndrome in people with coronary artery disease in Australia and New Zealand.

OBJECTIVES: To report time from the onset of symptoms to hospital presentation in Australian and New Zealand patients with subsequently confirmed acute coronary syndrome, and to identify factors associated with prehospital delay time in these patients. METHODS: Patients with coronary artery disease enrolled in a randomized clinical trial testing an intervention to reduce delay in responding to acute coronary syndrome symptoms had been followed for 24 months. In cases of admission to the ED for possible acute coronary syndrome, medical records were reviewed to determine the diagnosis, prehospital delay time, mode of transport to the hospital and aspirin use before admission. Clinical and demographic data were taken from the trial database. RESULTS: Patients (n= 140) had an average (SD) age of 67.3 (11.5) years; 36% were female. Two-thirds of patients went to hospital by ambulance and 89.3% had a final diagnosis of unstable angina. The median time from onset of symptoms to arrival at the ED was 2 h and 25 min (interquartile range 1:25-4:59); 12.1% arrived ≤ 1 h and 66% within 4 h. Multiple linear regression analysis showed that use of ambulance (Beta = 0.247, P= 0.012) and younger age (Beta = 0.198, P= 0.043) were independent predictors of shorter delay times. CONCLUSION: The time from the onset of symptoms to hospital presentation was too long for maximal benefit from treatment in most patients. Further efforts are needed to reduce treatment-seeking delay in response to symptoms of acute coronary syndrome.

Assessment of coronary plaque characteristics by optical coherence tomography in patients with diabetes mellitus complicated with unstable angina pectoris.

BACKGROUND: Diabetic patients are characterised by poorer prognosis and more cardiovascular complications compared with non-diabetic patients, which may be due to metabolic abnormalities and atherosclerotic plaque characteristics. METHODS: Patients with unstable angina pectoris were enrolled in the study and divided into diabetes mellitus (DM) (patients, n=25; plaques, n=42) and non-DM (patients, n=53; plaques, n=65) groups according to their DM history. Optical coherence tomography (OCT) examinations were performed on all patients, and images were analysed by two independent investigators. Fibrous cap thickness was measured at the thinnest point of each plaque. The presence of plaque disruption, dissection, erosion, thrombosis and calcification were also noted. RESULTS: Calcified plaques in the DM group were significantly greater than those in the non-DM group (42.9% vs. 23.1%; p=0.03). Thin-cap fibroatheroma (TCFA) were detected, and no significant difference was found in the frequencies (42.9% vs. 52.3%; p=0.34) and fibrous cap thickness (57.08 ± 6.20 µm vs. 56.11 ± 9.23 µm, p=0.74) between the DM and non-DM groups. Thrombus and plaque erosion were similar in the two groups, but the frequency of dissection in the DM group was greater than that in the non-DM group (21.4% vs. 7.7%, p=0.04). The high sensitivity C-reactive protein between the two groups was similar (0.44 ± 0.20mg/dl vs. 0.46 ± 0.15 mg/dl, p=0.83). CONCLUSION: Higher calcification and dissection were detected in diabetic patients with unstable angina pectoris, and the difference in coronary plaque characteristics can explain the difference in clinical prognoses between DM and non-DM patients.

Contemporary treatment of unstable angina and non-ST-segment-elevation myocardial infarction (part 1).

In this, the 1st part of a 2-part review, we discuss how plaque rupture is the most common underlying pathophysiologic cause of unstable angina and non-ST-segment-elevation myocardial infarction and how early risk stratification is vital in the timely diagnosis and treatment of acute coronary syndrome. Part 2 of this review (to be published in a later issue of this journal) will focus mainly on the various pharmacologic agents and treatment approaches (early invasive vs early conservative) to the management of unstable angina and non-ST-segment-elevation myocardial infarction.

Prediction of cardiac events in patients with reduced left ventricular ejection fraction with dobutamine cardiovascular magnetic resonance assessment of wall motion score index.

OBJECTIVES: The purpose of this study was to assess the utility of dobutamine cardiovascular magnetic resonance (DCMR) results for predicting cardiac events in individuals with reduced left ventricular ejection fraction (LVEF). BACKGROUND: It is unknown whether DCMR results identify a poor cardiac prognosis when the resting LVEF is moderately to severely reduced. METHODS: Two hundred consecutive patients ages 30 to 88 (average 64) years with an LVEF 40%. CONCLUSIONS: In individuals with mild to moderate reductions in LVEF (40% to 55%), dobutamine-induced increases in WMSI forecast MI and cardiac death to a greater extent than an assessment of resting LVEF. In those with an LVEF <40%, a dobutamine-induced increase in WMSI does not predict MI and cardiac death beyond the assessment of resting LVEF.