Frequency of Acute Coronary Syndrome in Patients with Normal Electrocardiogram Performed during Presence or Absence of Chest Pain

Objectives: The authors hypothesized that patients with active chest pain at the time of a normal electrocardiogram (ECG) have a lower frequency of acute coronary syndrome (ACS) than patients being evaluated for chest pain but with no active chest pain at the time of a normal ECG. The study objective was to describe the association between chest pain in patients with a normal ECG and the diagnosis of ACS. Methods: This was a prospective observational study of emergency department (ED) patients with a chief complaint of chest pain and an initial normal ECG admitted to the hospital for chest pain evaluation over a 1-year period. Two groups were identified: patients with chest pain during the ECG and patients without chest pain during the ECG. Normal ECG criteria were as follow: 1) normal sinus rhythm with heart rate of 55–105 beats/min, 2) normal QRS interval and ST segment, and 3) normal T-wave morphology or T-wave flattening. “Normal” excludes pathologic Q waves, left ventricular hypertrophy, nonspecific ST-T wave abnormalities, any ST depression, and discrepancies in the axis between the T wave and the QRS. Patients’ initial ED ECGs were interpreted as normal or abnormal by two emergency physicians (EPs); differences in interpretation were resolved by a cardiologist. ACS was defined as follows: 1) elevation and characteristic evolution of troponin I level, 2) coronary angiography demonstrating >70% stenosis in a major coronary artery, or 3) positive noninvasive cardiac stress test. Chi-square analysis was performed and odds ratios (ORs) are presented. Results: A total of 1,741 patients were admitted with cardiopulmonary symptoms; 387 met study criteria. The study group comprised 199 males (51%) and 188 females (49%), mean age was 56 years (range, 25–90 years), and 106 (27%) had known coronary artery disease (CAD). A total of 261 (67%) patients experienced chest pain during ECG; 126 (33%) patients experienced no chest pain during ECG. There was no difference between the two groups in age, sex, cardiac risk factors, or known CAD. The frequency of ACS for the total study group was 17% (67/387). There was no difference in prevalence of ACS based on the presence or absence of chest pain (16% or 42/261 vs. 20% or 25/126; OR = 0.77, 95% confidence interval = 0.45 to 1.33, p = 0.4). Conclusions: Contrary to our hypothesis concerning patients who presented to the ED with a chief complaint of chest pain, our study demonstrated no difference in the frequency of acute coronary syndrome between patients with chest pain at the time of acquisition of a normal electrocardiogram and those without chest pain during acquisition of a normal electrocardiogram.     

Adverse Cardiac Events in Emergency Department Patients with Chest Pain Six Months after a Negative Inpatient Evaluation for Acute Coronary Syndrome

OBJECTIVE: To evaluate the impact of the diagnostic test setting-inpatient versus outpatient-on adverse cardiac events (ACEs) after six months in emergency department (ED) patients with chest pain who were admitted to the hospital and subsequently had a negative evaluation for acute coronary syndrome (ACS). METHODS: The authors retrospectively studied a consecutive sample of ED patients with chest pain over a nine-month period. All patients were admitted to the hospital and underwent negative evaluations for ACS, defined as the absence of diagnostic changes on serial electrocardiograms or cardiac markers (creatine kinase-MB and troponin T), and a negative diagnostic cardiac study. Subjects were classified according to cardiac diagnostic study setting-either inpatient or outpatient. Diagnostic testing included exercise treadmill, angiography, stress echocardiography, or stress thallium scans. Acute cardiac events at six months were defined as cardiac death, myocardial infarction, unstable angina, cardiac arrest, or emergent revascularization. RESULTS: The six-month rate of ACEs among 157 subjects was 14%, with 2% cardiac mortality. The outpatient group had higher ACE risk when compared with the inpatient group using multivariate logistic regression, both for the entire cohort (OR 3.5, p < 0.03) and for a subgroup excluding patients with prior coronary artery disease (OR 6.7, p < 0.05). The outpatient group included 19 of 52 (37%) noncompliant subjects who did not receive a diagnostic study. CONCLUSIONS: Long-term cardiac morbidity of patients after a negative ACS evaluation may be higher than previously thought. Risk of ACE is significantly higher in subjects scheduled for outpatient diagnostic tests. Inpatient diagnostic testing is justified for subjects at risk for poor compliance.     

Derivation and Validation of a Risk Stratification Model to Identify Coronary Artery Disease in Women Who Present to the Emergency Department with Potential Acute Coronary Syndromes

OBJECTIVES: To derive and validate a model to identify women who would benefit from further evaluation of chest pain after an initial negative emergency department (ED) evaluation for acute coronary syndrome (ACS). METHODS: The derivation and validation cohorts were comprised of women who presented to the ED with chest pain at two university hospitals. Patients were excluded if the initial electrocardiogram (ECG) or cardiac markers were consistent with ACS. Patients were followed for 30 days after the index visit to identify evidence of coronary artery disease (CAD), which was defined as a positive diagnostic study, myocardial infarction, or death. The authors performed a logistic regression analysis to identify significant predictors of CAD. A scoring system was developed based on the B-coefficient of these significant predictors. Levels of risk were assigned by summing and categorizing the cumulative risk score into low-, moderate-, and high-risk groups. RESULTS: The derivation and validation sets were comprised of 733 and 2,440 women, respectively. From the derivation set predictors of CAD (score) were history of CAD (1), age > or = 60 years (1), and high clinical suspicion (3). Low risk was defined as a score = 0, moderate risk score = 1-2, high risk score > or = 3. In the validation set, the numbers of patients with evidence of CAD were four of 1,348 (0.30%), 18 of 498 (3.6%), and 71 of 594 (11.9%) in the low-, moderate-, and high-risk groups, respectively. CONCLUSIONS: The risk of underlying CAD in women who present to the ED with potential ACS may be determined using a simple risk stratification score.     

Ultrasound Measurement of Carotid Intima–Media Thickness and Plaques in Predicting Coronary Artery Disease

Ultrasound measurement of carotid intima–media thickness (CIMT) and plaque thickness (PT) may be an additional tool for risk stratification of patients with suspected acute coronary syndrome (ACS) in the emergency department (ED). The aim of this study was to evaluate the correlation of CIMT and PT with coronary artery disease (CAD) in risk stratification tests.This prospective observational study was conducted in an academic tertiary care ED. Carotid ultrasound measurements were obtained for emergency patients with suspected ACS. Carotid measurements included PT, mean CIMT and maximum CIMT. The correlations between carotid ultrasound and the results of coronary catheter angiography (CA), coronary computed tomography angiography (CCTA) and stress tests were identified. The convenience sample included 58 patients comprising 39 men and 19 women with a mean age of 60 ± 12 y. Twenty-two percent (13/58) of patients were positive for CAD, as indicated by results of the cardiac risk stratification tests. Presence of plaque correlated with CCTA findings, with a high specificity (92.8%) for a positive test. Max CIMT predicted abnormal CCTA (area under the curve [AUC] = 0.93, 95% confidence interval: 0.80–1). The correlations with stress test (0.78, 0.46–1) and CA (0.55, 0.28–0.82) were weaker. Presence of carotid plaque correlated significantly with findings of CAD on all risk stratification tests, but especially with CCTA. Carotid ultrasound could have a role in risk stratification in the ED, though more research is needed.     

Stress testing before discharge is not required for patients with low and intermediate risk of acute coronary syndrome after emergency department short stay assessment

Objective: To investigate the usefulness of stress testing before discharge in patients assessed low to intermediate risk of acute coronary syndrome (ACS). Methods: A prospective observational study was undertaken of patients presenting to the ED with suspected myocardial ischaemia. After negative initial electrocardiogram (ECG) and serum troponin testing, patients were admitted to the emergency short stay unit (ESSU) for further evaluation using a chest pain protocol that included stress testing as the final risk stratification tool. The primary outcome measure was evidence of myocardial ischaemia at stress testing. Results: Of the 300 patients enrolled and followed up, there were no deaths at 30 days and no myocardial infarcts in patients discharged from the short stay. Two patients (0.67%) had positive serum troponin levels at 6 h after the onset of chest pain and were diagnosed with non‐ST segment elevation myocardial infarctions. Three patients (1%) had abnormal stress testing and were admitted to hospital from ESSU. On review, all three patients were high risk, according to The National Heart Foundation of Australia/Cardiac Society of Australia and New Zealand guidelines. Conclusion: The present study showed that an ED short stay unit can effectively evaluate and manage patients with low and intermediate risk of ACS. The study suggests that patients with low and intermediate risk for ACS might safely be discharged after normal serial ECG and cardiac biomarkers, with a view to early outpatient stress testing. With strict adherence to admission criteria, there does not appear to be any benefit of stress testing before discharge.     

Sixty-four–slice Computed Tomography of the Coronary Arteries: Cost–Effectiveness Analysis of Patients Presenting to the Emergency Department with Low-risk Chest Pain

Objectives: The aim was to use a computer model to estimate the cost–effectiveness of 64‐slice multidetector computed tomography (MDCT) of the coronary arteries in the emergency department (ED) compared to an observation unit (OU) stay plus stress electrocardiogram (ECG) or stress echocardiography for the evaluation of low‐risk chest pain patients presenting to the ED. Methods: A decision analytic model was developed to compare health outcomes and costs that result from three different risk stratification strategies for low‐risk chest pain patients in the ED: stress ECG testing after OU care, stress echocardiography after OU care, and MDCT with no OU care. Three patient populations were modeled with the prevalence of symptomatic coronary artery disease (CAD) being very low risk, 2%; low risk, 6% (base case); and moderate risk, 10%. Outcomes were measured as quality‐adjusted life years (QALYs). Incremental cost–effectiveness ratios (ICERs), the ratio of change in costs of one test over another to the change in QALY, were calculated for comparisons between each strategy. Sensitivity analyses were conducted to test the robustness of the results to assumptions regarding the characteristics of the risk stratification strategies, costs, utility weights, and likelihood of events. Results: In the base case, the mean (±standard deviation [SD]) costs and QALYs for each risk stratification strategy were MDCT arm $2,684 (±$1,773 to $4,418) and 24.69 (±24.54 to 24.76) QALYs, stress echocardiography arm $3,265 (±$2,383 to $4,836) and 24.63 (±24.28 to 24.74) QALYs, and stress ECG arm $3,461 (±$2,533 to $4,996) and 24.59 (±24.21 to 24.75) QALYs. The MDCT dominated (less costly and more effective) both OU plus stress echocardiography and OU plus stress ECG. This resulted in an ICER where the MDCT arm dominated the stress echocardiography arm (95% confidence interval [CI] = dominant to $29,738) and where MDCT dominated the ECG arm (95% CI = dominant to $7,332). The MDCT risk stratification arm also dominated stress echocardiography and stress ECG in the 2 and 10% prevalence scenarios, which demonstrated the same ICER trends as the 6% prevalence CAD base case. The thresholds where the MDCT arm remained a cost‐saving strategy compared to the other risk stratification strategies were cost of MDCT, <$2,097; cost of OU care, >$1,092; prevalence of CAD, <70%; MDCT specificity, >65%; and a MDCT indeterminate rate, <30%. Conclusions: In this computer‐based model analysis, the MDCT risk stratification strategy is less costly and more effective than both OU‐based stress echocardiography and stress ECG risk stratification strategies in chest pain patients presenting to the ED with low to moderate prevalence of CAD. ACADEMIC EMERGENCY MEDICINE 2008; 15:1–10 © 2008 by the Society for Academic Emergency Medicine     

HEARTS3对提高急诊非ST段抬高胸痛危险分层作用的研究

目的 在HEART评分系统基础上,研究HEARTS3评分对提高急诊非ST段抬高胸痛患者危险分层和急性冠脉综合征(ACS)的预测应用价值.方法 回顾性分析2011年7月至2015年5月775例符合标准的急诊非ST段抬高胸痛患者,分别进行HEART和HEARTS3评分,并随访患者发病后30 d内ACS和心肌梗死(MI)发病情况,根据评分进行危险分层,分析不同分层患者发病后30 dACS与MI的发生情况与评分之间的关系,并比较两种评分对胸痛患者发病后30 d ACS的预测能力.使用SPSS 13.0软件进行统计分析计数资料以百分比(％)表示,两组计量资料之间的比较用成组t检验,两种评分不同评分段患者发生ACS比例比较用行x列表x2检验,每种评分方法对发生心血管事件ACS患者分辨度用ROC曲线下面积(AUROC),并用Z检验进行比较.结果 共有92例发病后30 d发生ACS,HEART和HEARTS3的对高危胸痛患者预测敏感性分别为64.79％、77.97％,特异性分别为97.57％、97.85％.HEART与HEARTS3危险评分ROC曲线下面积,MI(0.952 vs.0.813;P =0.028),30 dACS (0.913 vs.0.815;P=0.034),两者差异具有统计学意义.结论 HEART和HEARTS3都可以应用于急诊胸痛患者的危险分层和预后评估,但HEARTS3更可靠.     

脂蛋白相关磷脂酶A2在冠心病患者严重程度评估中的应用

目的评估脂蛋白相关磷脂酶A2(Lp-PLA2)在冠心病患者严重程度评估及远期心血管事件发生预测中的价值。方法将165例因胸痛行冠状动脉造影的患者按造影结果分为冠心病组98例[其中稳定性心绞痛(SAP)患者59例、急性冠状动脉综合症(ACS)患者39例]和非冠心病组67例。冠心病组按照病变累及的冠状动脉支数分为单支、二支和三支组,同时对每位冠心病患者进行Gensini评分。检测所有患者入院后24 h内的血浆Lp-PLA2及总胆固醇(TC)和低密度脂蛋白胆固醇(LDL-C)水平。随访1～2年,记录主要不良心血管事件。分析不同病例组别、不同病变支数和有、无发生主要不良心血管事件患者的Lp-PLA2水平差异。结果冠心病患者Lp-PLA2水平明显高于非冠心病组(P<0.01),ACS患者Lp-PLA2水平高于SAP患者(P<0.05)。冠心病组TC和LDL-C水平与非冠心病组比较均无差异。冠心病三支病变组Lp-PLA2水平明显高于单支和二支病变组(P<0.01、P<0.05),而单支、二支病变组间无差异(P>0.05)。不良心血管事件阳性患者Lp-PLA2水平明显高于阴性患者(P<0.01)。结论 Lp-PLA2可用于...     

Performance of a Population-based Cardiac Risk Stratification Tool in Asian Patients with Chest Pain

Objectives: Most contemporary cardiac risk stratification tools have been derived and validated in mixed-race populations. Their validity in single-race populations has not been tested. The authors sought to compare the performance of a risk stratification tool between a mixed-race U.S. patient population and an Asian patient population. Methods: This study is an analysis of data from the Internet Tracking Registry for Acute Coronary Syndromes (i*tr ACS ) registry of patients with chest pain presenting to the emergency departments of eight U.S. centers and one site in Singapore. The Acute Cardiac Ischemia Time-Insensitive Predictive Instrument (ACI-TIPI) was computed for included patients, and its performance in predicting acute coronary syndrome (ACS) was compared between patients from the United States and Singapore. Results: Of the 11,991 included patients, 1,120 experienced ACS. Although the ACI-TIPI demonstrated similar accuracy among groups (area under the curve, 0.729 [U.S.] vs. 0.719 [Singapore]; p = 0.5611), sensitivity and specificity were different when equal ACI-TIPI thresholds were considered. Recreating the logistic regression models used to create the ACI-TIPI showed similar results between the derived parameters and the parameters estimated for the U.S. group. In contrast, age older than 50 years (log-odds ratio [LOR], 0.107; 95% confidence interval [CI] = 0.518 to 0.713), male gender (LOR, 0.487; 95% CI = 0.149 to 1.122), and chest pain as a primary complaint (LOR, 0.237; 95% CI = 0.139 to 0.613) had little predictive power in patients from Singapore. Conclusions: Differences exist in presentation and factors associated with ACS among patients from the United States and Singapore that may affect the performance of risk stratification tools. These findings suggest that cardiac clinical decision rules need international validation.     

The role of the heart-type fatty acid binding protein in the early diagnosis of acute coronary syndrome and its comparison with troponin I and creatine kinase-MB isoform

Objectives

The aim of this study was to research the effectiveness of the heart-type fatty acid binding protein (H-FABP) in the early diagnosis of acute coronary syndrome (ACS) in patients admitted to emergency service (ES) within 6 hours of onset of chest pain.

Equipment and Method

A total of 83 patients admitted with chest pain to our ES were included in this study. The patients were divided into 2 groups: those with a diagnosed ACS and those diagnosed with non–cardiac-related chest pain. Patients were also were divided into 2 groups according to the time of admission: those admitted within 0 to 3 hours and 3 to 6 hours of onset of chest pain. Peripheral venous blood samples were obtained from all patients for H-FABP, troponin I, and creatine kinase-MB (CK-MB) serum concentration measurements.

Results

Of a total of 83 patients, 21.6% (n = 18) were in the control group and 78.3% (n = 65) were in the ACS group. The average H-FABP value for the patients in the control group was 0.86 ± 0.54 ng/mL. When the ACS and control groups were compared in means of cardiac markers for CK-MB (P = .000) and H-FABP (P = .000), there was a statistically significant difference, whereas no difference was observed for troponin I (P = .013). In the ACS group, H-FABP sensitivity for diagnosis was found to be 98% and specificity was 71%; CK-MB sensitivity was 86% and specificity was 52%; and troponin I sensitivity was 77% and specificity was 20%.

Conclusions

For patients admitted with chest pain to ES, H-FABP was found to be more sensitive and specific than troponin I and CK-MB in the early diagnosis of ACS.     

The absence of coronary artery calcification does not rule out the presence of significant coronary artery disease in Asian patients with acute chest pain

The absence of coronary artery calcification (CAC) has been used to as an indication to rule out significant coronary artery disease (CAD). However, diagnostic usefulness of ‘zero calcium score criteria’ as a decision-making strategy to rule out significant CAD as the etiology of acute chest pain has not been studied in depth, especially in Asian ethnicity. We prospectively enrolled 136 Korean patients (58% men, 56 ± 13 years) who presented to the emergency department (ED) with acute chest pain and non-diagnostic ECG. All patients underwent 64-slice CT for calcium scoring and coronary CT angiography (cCTA). We investigated the association of CAC with the presence of ≥50% CAD on cCTA and with a final diagnosis of an acute coronary syndrome (ACS). Ninety-two patients out of 136 (68%) did not show detectable CAC, and 14 out of these 92 without CAC (15%) had ≥50% CAD on cCTA. Sensitivity, specificity, positive predictive value and negative predictive value of zero calcium score criteria for the detection of ≥50% CAD were 0.66 (95% confidence interval, 0.50–0.80), 0.83 (0.74–0.90), 0.64 (0.48–0.77), 0.85 (0.75–0.91), respectively. Patients who had ≥50% CAD without detectable CAC were younger (P = 0.001), and had a higher prevalence of smoking (P = 0.048) as compared to patients with a degree of CAC. Most of the patients with ≥50% CAD of non-calcified plaque were younger than 60 years of age (79%, 11/14), however, 3 of them were older than 60 years of age. Forty-five patients (33%) were subsequently diagnosed as having ACS, and 38% (17/45) of them had no CAC. Zero calcium score did not necessarily guarantee the absence of significant CAD, even in patients older than 60 years, in Asian ethnicity presenting to the ED with chest pain.     

Acute Coronary Syndrome in Octogenarians: Expect the Unexpected

Background

Ischemic heart disease is the leading cause of death in the United States and the world. Advanced age is the strongest risk factor for ischemic heart disease and the best independent predictor for poor outcomes after acute coronary syndrome (ACS). Elderly patients are at high risk for ACS, and numerous studies have shown that octogenarians in particular experience increased morbidity and mortality compared to younger patients.

Diagnostic yield of coronary angiography in patients with acute chest pain: role of noninvasive test

Objectives

This study investigated the diagnostic yield of invasive coronary angiography (CAG) and the impact of noninvasive test (NIV) in patients presented to emergency department (ED) with acute chest pain.

Methods

Patients 50 years or older who visited ED with acute chest pain and underwent CAG were identified retrospectively. Those with ischemic electrocardiogram, elevated cardiac enzyme, known coronary artery disease (CAD), history of cardiac surgery, renal failure, or allergy to radiocontrast were excluded. Diagnostic yields of CAG to detect significant CAD or differentiate the need for revascularization were analyzed according to whether NIV was performed and its result.

Results

Among the total 375 consecutive patients, significant CAD was observed in 244 (65.1%). Diagnostic yields of CAG were higher in patients who underwent NIV before CAG, but the discriminative effect was modest (59.7% vs 70.7% [P = .026] for detection of CAD; 45.0% vs 50.5% [P = .285] for revascularization). Positive results of NIV were significantly associated with the presence of CAD and the need for revascularization, when compared with patients without NIV or patients with negative results (P < .001, respectively).

Conclusion

The diagnostic yield of CAG was only 65% in low- to intermediate-risk ED patients with acute chest pain. Performing of NIV provided only modest improvement in diagnostic yield of CAG. The unexpectedly low diagnostic yield might be attributable to the underuse of NIV and misinterpretation of physicians. We suggest the use of NIV as a gatekeeper to discriminate patients who require CAG and/or revascularization, and for this, better risk stratification and appropriate application of NIV are required.     

Are there symptom differences in patients with coronary artery disease presenting to the ED ultimately diagnosed with or without ACS?

Objectives

Symptoms are compared among patients with coronary artery disease (CAD) admitted to the emergency department with or without acute coronary syndrome (ACS). Sex and age are also assessed.

Methods

A secondary analysis from the PROMOTION (Patient Response tO Myocardial Infarction fOllowing a Teaching Intervention Offered by Nurses) trial, an multicenter randomized controlled trial, was conducted.

Results

Of 3522 patients with CAD, at 2 years, 565 (16%) presented to the emergency department, 234 (41%) with non-ACS and 331 (59%) with ACS. Shortness of breath (33% vs 25%, P = .028) or dizziness (11% vs 3%, P = .001) were more common in non-ACS. Chest pain (65% vs 77%, P = .002) or arm pain (9% vs 21%, P = .001) were more common in ACS. In men without ACS, dizziness was more common (11% vs 2%; P = .001). Men with ACS were more likely to have chest pain (78% vs 64%; P = .003); both men and women with ACS more often had arm pain (men, 19% vs 10% [P = .019]; women, 26% vs 13% [P = .023]). In multivariate analysis, patients with shortness of breath (odds ratio [OR], 0.617 [confidence interval [CI], 0.410-0.929]; P = .021) or dizziness (OR, .0311 [CI, 0.136-0.708]; P = .005) were more likely to have non-ACS. Patients with prior percutaneous coronary intervention (OR, 1.592 [CI, 1.087-2.332]; P = .017), chest pain (OR, 1.579 [CI, 1.051-2.375]; P = .028), or arm pain (OR, 1.751 [CI, 1.013-3.025]; P <.042) were more likely to have ACS.

Conclusions

In patients with CAD, shortness of breath and dizziness are more common in non-ACS, whereas prior percutaneous coronary intervention and chest or arm pain are important factors to include during ACS triage.     

生长分化因子15对急性胸痛早期诊断价值分析

目的:探索生长分化因子15（growth differentiation factor15,GDF15）在急性胸痛中的早期诊断价值。方法:回顾性收集2020年1月至11月于解放军总医院海南医院急诊科就诊的急性胸痛患者96名纳入研究。记录患者性别、年龄、入院30 min内患者的肌钙蛋白T、肌酸激酶、肌酸激酶同工酶、GDF15、B型钠尿肽,比较不同组各个指标的差异。绘制ROC曲线,评价GDF15与TnT/BNP对急性冠脉综合征（acute coronary syndrome,ACS）诊断价值。统计各个患者的Gensini评分、左室射血分数、住院滞留天数以及支架植入个数,评价这些指标与GDF15浓度的相关关系。结果:急性胸痛中总的趋势呈现男多女少（72.92 vs. 27.08,%）,年龄最大的组别为UA组,年龄为（64.67±13.87）岁,年龄最小的组别是呼吸心搏骤停组,仅为（47.29±9.99）岁。STEMI组、NSTEMI组、UA组中既往罹患高血压病比例较高,所有组别均未在既往罹患糖尿病中表现出明显优势。所有心肌标记物组间差异均有统计学意义,GDF15在ACS相关性胸痛组浓度更高[（2.360±1.710） ng/mL vs. （1.380±1.040） ng/mL, P<0.01]。GDF15与TnT联合对于诊断ACS相关性胸痛的价值最高,其工作特征曲线下面积（the area under the receiver operating characteristic,AUC）可达0.863。GDF15浓度与心脏射血分数负相关,Gensini评分正相关,植入支架个数正相关,患者住院天数正相关。 结论:GDF15在急性胸痛中具有很好的诊断及预后预测价值。GDF15与TnT联合可提高ACS诊断率。     

cTnT与CK--MB在胸痛危险分层中的作用

目的评价心肌肌钙蛋白T(cTnT)与肌酸激酶同工酶-MB(CK-MB)蛋白量在胸痛危险分层中的作用。方法对所有病例进行12h床边动态监测，包括基线、4、8、12h的连续心律监测和12导联心电图(ECG)测试；与此同时分别于基线、4、8、12h对入选胸痛组的其中383例患者测定cTnT、CK-MB。结果383例CPU患者只有8例(2．1％)CK-MB阳性，39例cTnT阳性。cTnT状态与随访的结果表明，cTnT阳性明显早于CK-MB。89％cTnT阳性患者血管造影术显示发生冠状动脉疾病(CAD)及多支血管病。结论cTnT比CK-MB在评估伴心肌坏死和多支血管病的胸痛危险分层中具有更高的敏感性与特异性；常规测定cTnT更便于胸痛的危险分层与处理。