Management Strategies for a Better Outcome in Unstable Coronary Artery Disease

Unstable coronary artery disease is a term encompassing both unstable angina and non-Q-wave (non-ST-segment elevation) myocardial infarction. Patients with these conditions are at risk of early progression to acute myocardial infarction and death. Thus, management of these conditions must aim to reduce long-term mortality and morbidity. Risk stratification is crucial for the identification of patients whose risk of early progression is high; they may require coronary angiography and (if suitable) either percutaneous transluminal coronary angioplasty or coronary artery bypass surgery. No single variable can accurately predict risk, but considerable data are emerging to show that biochemical markers of myocardial injury, such as troponin-T and troponin-I, are valuable in combination with electrocardiographic findings and clinical features. Routine early invasive procedures (coronary angiography with or without revascularization) have not yet been shown to have any significant advantage over conservative regimens for the majority of patients. Antiplatelet, anticoagulant, and anti-ischemic agents remain the mainstay of treatment in the acute phase. New agents, such as glycoprotein IIb/IIIa receptor inhibitors and low-molecular-weight heparins, as well as antithrombins and Factor Xa inhibitors add to the treatments currently available. Thrombolytic agents are contraindicated in the absence of ST-segment elevation. After clinical stabilization, ongoing assessment should include exercise testing for all patients who are able; other imaging techniques should be used for patients unable to exercise. A profile indicating a high risk of future events is an indication for elective angiography and consideration for revascularization.     

冠状动脉易损斑块的治疗进展

动脉粥样硬化是全身性、慢性炎症性疾病,以局部突出表现为主。冠状动脉粥样硬化是冠状动脉性心脏病最主要病因,冠状动脉性心脏病患者发生急性冠状动脉事件的后果十分严重,常危及生命,而易损斑块是导致急性冠状动脉综合征主要罪犯病变。因此,对易损斑块的早期识别以及积极干预,对于预防急性心血管事件的发生至关重要,具有非常重要的临床意义。现就冠状动脉易损斑块的治疗最新进展做一综述。     

光学相干断层成像在检测易损斑块中的应用价值

冠状动脉粥样硬化斑块易发斑块破裂,导致急性冠状动脉综合征,引起急性心肌梗死。有效的评价斑块的结构及成份特点,监测其演变过程,对选择治疗时机和治疗方案有重要意义。光学相干断层成像是一种新型的生物医学成像技术,它可以对易损斑块准确识别。现就光学相干断层成像在检测易损斑块中的应用价值作一综述。     

Performance of the coronary calcium score in an outpatient chest pain clinic and strategies for risk stratification

BackgroundCoronary artery calcium score (CAC) is an objective marker of atherosclerosis. The primary aim is to assess CAC as a risk classifier in stable coronary artery disease (CAD).HypothesisCAC improves CAD risk prediction, compared to conventional risk scoring, even in the absence of cardiovascular risk factor inputs.MethodsOutpatients presenting to a cardiology clinic (n = 3518) were divided into two cohorts: derivation (n = 2344 patients) and validation (n = 1174 patients). Adding logarithmic transformation of CAC, we built two logistic regression models: Model 1 with chest pain history and risk factors and Model 2 including chest pain history only without risk factors simulating patients with undiagnosed comorbidities. The CAD I Consortium Score (CCS) was the conventional reference risk score used. The primary outcome was the presence of coronary artery disease defined as any epicardial artery stenosis≥50% on CT coronary angiogram.ResultsArea under curve (AUC) of CCS in our validation cohort was 0.80. The AUC of Models 1 and 2 were significantly improved at 0.88 (95%CI 0.86–0.91) and 0.87 (95%CI 0.84–0.90), respectively. Integrated discriminant improvement was >15% for both models. At a pre‐specified cut‐off of ≤10% for excluding coronary artery disease, the sensitivity and specificity were 89.3% and 74.7% for Model 1, and 88.1% and 71.8% for Model 2.ConclusionCAC helps improve risk classification in patients with chest pain, even in the absence of prior risk factor screening.     

冠心病诊断指标的多变量研究

本文从６４例病人的临床资料中选出常用七种无创检查指标，共１４种变量，逐一量化后与冠脉造影结果进行比较。发现典型症状和ＥＣＧ适用于定性诊断，ＵＣＧ和Ｄ－ＥＣＧ可对程度作出一定判断。各变量综合评分与冠脉造影之间有良好的复相关，Ｒ值为０．８８８。其敏感性为９３％，特异性为８０％，阳性预测值为８７％，阴性预测值为８９％。综合评分的诊断意义在于节约诊断费用，易于评价无创指标。     

Exercise electrocardiography after acute coronary syndromes: Still the first testing modality?

Recent diagnostic and therapeutic advances have been questioning the role of exercise electrocardiography (ECG) for risk stratification of patients recovering from an acute coronary syndrome. The aim of this review was to verify whether evidence still exists supporting the use of exercise ECG as first choice stress testing modality in this clinical setting in the light of the most recent prognostic data and of cost effectiveness considerations. It was concluded that a large body of evidence supports the use of exercise ECG as a cost-effective tool for prognostic purposes and for quality of life assessment following acute coronary syndromes.