Chest pain in clinical practice: impact of routine troponin determination on clinical manifestations and care

INTRODUCTION AND OBJECTIVES. To study the significance of chest pain in the clinical practice of a Spanish hospital and to evaluate the impact of routine troponin determination. METHODS: In our institution, routine serial measurements of troponins I and T were made in the evaluation of chest pain in 2000. We compared the results obtained in 1999 for all patients who visited the emergency room for chest pain and the patients who were hospitalized. We recorded the diagnosis at discharge, duration of the hospital stay, and associated costs. RESULTS: In 2000, 1,820 patients with chest pain visited the emergency department, which was equivalent to 1.9% of visits and 7.5 cases per 1,000 people and year: 43% of these patients were hospitalized for suspected acute coronary syndrome as compared to 49% in 1999 (-12%; p > 0.001). Among the patients admitted, 28% were discharged with a diagnosis of non-ischemic chest pain. Troponin determinations were associated with a lower probability of admission due to unstable angina (11.5 vs 16.0%; -28%; p < 0.001) and non-ischemic chest pain (12.1 vs 14.5%; -16%; p < 0.05), and an increase in diagnoses of non-Q wave acute myocardial infarction (3.4% vs 1.8%; +89%; p < 0.01). Non-ST elevation acute coronary syndrome ACS required 3,751 days of hospitalization and 1,003,420 euros of cost, and troponin determinations were associated with a reduction in hospital stays of 832 days (-18.2%) and 185,100 euros (-15.6%). CONCLUSION: Chest pain had a high incidence, 7.5, and generates high costs in hospital admissions. The routine use of serial troponin determinations was associated with a reduction in hospital admissions due to unstable angina and non-ischemic chest pain, and costs.     

Usefulness of contrast stress-echocardiography or exercise-electrocardiography to predict long-term acute coronary syndromes in patients presenting with chest pain without electrocardiographic abnormalities or 12-hour troponin elevation

The evaluation of patients presenting to the hospital with a recent episode of chest pain suggestive of myocardial ischemia, nondiagnostic electrocardiographic findings, and normal 12-hour cardiac troponin levels remains a challenge for the clinician. We selected 1,081 consecutive patients who presented to the emergency department during 2008 for a chest pain complaint of suspected cardiac origin without significant electrocardiographic abnormalities or troponin elevation. These patients underwent either contrast-enhanced stress-echocardiography with myocardial perfusion imaging or exercise-electrocardiography within 5 days of the index admission. We analyzed their 1-year cardiac outcome (i.e., unstable angina, myocardial infarction, or cardiac death). A post test likelihood of cardiac events was determined on the basis of the results of the provocative testing. Significantly better event-free survival (log-rank p <0.0001) was found for both hard (cardiac death and nonfatal myocardial infarction) and combined (acute coronary syndrome) end points in patients with normal contrast-enhanced stress-echocardiographic findings. However, this was not the case for patients in the exercise-electrocardiographic group, for whom event-free survival was not significantly different among the 3 possible result categories (normal, indeterminate, and abnormal test findings; log-rank p = NS). In conclusion, inducible ischemia detected by contrast-enhanced stress-echocardiography predicted the 1-year incidence of acute coronary syndrome (11.3% for positive vs 0.8% for negative results). However, this was not the case for exercise-electrocardiography, with a 2.7%, 2.3%, and 2.9% 1-year incidence of acute coronary syndromes for positive, negative, and indeterminate results, respectively.     

Vasospastic reactions in patients with ischemic heart disease (data of the ergometrin test)

A study of 157 patients with verified or suspected coronary disease, subjected to the intravenous ergometrin test, is reported. A clear-cut correlation is demonstrated between the rate of clinically and electrocardiographically positive tests, the pattern of the pain syndrome and the clinical course of the disease. Vasospastic response was particularly common in patients with unstable angina. Of those, patients prone to attacks of acute coronary insufficiency in the presence of progressive angina with recent clinical coronary manifestations were particularly sensitive to ergometrin. Among patients with stable angina, angina of the higher functional classes was associated with a considerable rate of positive ergometrin tests. Vasoconstrictive response was rather uncommon in individuals with intact stress tolerance and spontaneous chest pains, suggestive of spontaneous angina. There were no vasospastic reactions in patients with the atypical pain syndrome.     

Chest pain in the emergency room. Importance of a systematic approach

OBJECTIVE: To evaluate the efficiency of a systematic diagnostic approach in patients with chest pain in the emergency room in relation to the diagnosis of acute coronary syndrome (ACS) and the rate of hospitalization in high-cost units. METHODS: One thousand and three consecutive patients with chest pain were screened according to a pre-established process of diagnostic investigation based on the pre-test probability of ACS determinate by chest pain type and ECG changes. RESULTS: Of the 1003 patients, 224 were immediately discharged home because of no suspicion of ACS (route 5) and 119 were immediately transferred to the coronary care united because of ST elevation or left bundle-branch block (LBBB) (route 1) (74% of these had a final diagnosis of acute myocardial infarction [AMI]). Of the 660 patients that remained in the emergency room under observation, 77 (12%) had AMI without ST segment elevation and 202 (31%) had unstable angina (UA). In route 2 (high probability of ACS) 17% of patients had AMI and 43% had UA, whereas in route 3 (low probability) 2% had AMI and 7 % had UA. The admission ECG has been confirmed as a poor sensitivity test for the diagnosis of AMI ( 49%), with a positive predictive value considered only satisfactory (79%). CONCLUSION: A systematic diagnostic strategy, as used in this study, is essential in managing patients with chest pain in the emergency room in order to obtain high diagnostic accuracy, lower cost, and optimization of the use of coronary care unit beds.     

Follow-up findings one year after discharge from a chest pain unit

One hundred and twenty five consecutive patients discharged from a chest pain unit (group I, 32 with the diagnosis of probable ischemic heart disease and group II, 93 with the diagnosis of non-vascular pain) were prospectively followed up for one year. In group I (treadmill exercise testing were positive at a high workload in 15, negative in 9 and inconclusive in 4), one patient had non-ST elevation acute coronary event 15 days after discharge and two patients had unstable angina at 3 and 5 months. There were no events among the patients who had positive or inconclusive exercise testing. In group II (treadmill exercise testing were negative in 85 and inconclusive in 5) one patient had non-ST elevation acute coronary event at 7 months and one had unstable angina at 11 months. In conclusion, patients discharged from a chest pain unit, including those patients with positive treadmill exercise at a high workload, have a favorable mid-term outcome.     

Das akute Koronarsyndrom

Acute coronary syndrome is one of the most common reasons for a presentation in an emergency room. The biggest component of the overall mortality in adults is acute coronary syndrome or in this context its complications. The term “acute coronary syndrome” comprises on one hand 3 entities – unstable angina pectoris, Non-ST-elevation myocardial infarction and ST-elevation myocardial infarction. On the other hand particularly in emergency medicine the term is used as a working diagnosis for patients with unclear, acute chest pain. Although the underlying disease has not changed, especially with the introduction of troponins and the changes of their reference values the concept and importance of acute myocardial infarction has changed. This article emphazises on the current nomenclature and its importance for the adequate diagnosis and treatment are explained.     

Chest pain centers: diagnosis of acute coronary syndromes

Chest pain centers in the emergency department have generally been accepted as a safe, cost-effective, and rapid approach to the evaluation, triage, and management of patients with potential acute coronary syndromes. These centers were initially designed to enhance patient care by decreasing time to treatment for acute myocardial infarction (AMI) and rapidly identifying patients with unstable angina. They also included community outreach and educational objectives designed to reduce time from the onset of chest pain to ED presentation. In the past decade, health care financial constraints have created additional impetus to the development of chest pain centers. Cost reduction efforts have occurred to reduce hospitalizations, lengths of stay, and unnecessary treatments and procedures. Practitioners and administrators try to balance these goals with the imperative to provide high-quality patient care. Protocol-driven approaches have been developed for specific disease processes in emergency settings. The chest pain center concept is such an approach for patients with chest pain. Chest pain is the second most common ED presenting complaint and is a symptom related to the leading cause of death in the United States, coronary artery disease (CAD). One third of ED patients with chest pain will eventually have a diagnosis of acute coronary syndrome. Many patients with acute coronary syndromes have atypical presentations that are not diagnosed in the ED with the traditional diagnostic evaluation of a history, physical examination, and 12-lead ECG. If they are not admitted to the hospital for further evaluation, the diagnosis may be missed. The 2% to 5% of AMI patients who are inadvertently released home often have poor outcomes and result in a leading cause of malpractice suits in emergency medicine. More than one half of ED patients with chest pain have clinical findings after their initial evaluation consistent with acute coronary syndromes and are admitted to the hospital. Approximately one half of these patients, after evaluation in the hospital, are found not to have acute coronary syndromes. The cost for these negative inpatient cardiac evaluations has been estimated to be $6 billion in the United States each year. Today, chest pain centers serve as an integral component of many EDs. Their success and safety is the result of a focused, protocol-driven approach directed at the acute coronary syndrome continuum from unstable angina to transmural Q-wave myocardial infarction. New therapies for acute coronary syndromes make ED triage and risk stratification increasingly important. Although different chest pain center protocols have proved effective, all address the diagnosis and rapid treatment of acute myocardial necrosis, rest ischemia, and exercise-induced ischemia. Identifying patients with coronary artery disease in one of these stages in the spectrum of myocardial ischemia is the foundation for a successful chest pain center in the ED.     

Value of early exercise stress testing in a chest pain unit protocol

Early exercise testing (first 24 hours) was evaluated in the stratification of patients seen in the emergency room for chest pain. One hundred and forty-two consecutive patients without ischemia in the ECG or troponin I elevation were included. Ninety-two patients were discharged after the exercise testing (group I, 82 negative and 10 inconclusive test results) and 50 patients were hospitalized (group II, 29 positive and 21 inconclusive test results). In group I, cardiac events (unstable angina and non-fatal infarction) occurred in the next 30 days of follow-up in 2 patients with inconclusive test results; no cardiac events occurred in patients with negative test results. In group II, unstable angina was diagnosed in 30 patients and 3 presented recurrent angina. There were no complications during exercise testing. In conclusion, early exercise testing is safe and useful in the stratification of patients seen in the emergency room for chest pain. Only patients with negative test results should be discharged early.     

Chest pain units: a modern way of managing patients with chest pain in the emergency department

It is estimated that 5 to 8 million individuals with chest pain or other symptoms suggestive of myocardial ischemia are seen each year in emergency departments (ED) in the United States 1,2, which corresponds to 5 to 10% of all visits 3,4. Most of these patients are hospitalized for evaluation of possible acute coronary syndrome (ACS). This generates an estimated cost of 3 - 6 thousand dollars per patient 5,6. From this evaluation process, about 1.2 million patients receive the diagnosis of acute myocardial infarction (AMI), and just about the same number have unstable angina. Therefore, about one half to two thirds of these patients with chest pain do not have a cardiac cause for their symptoms 2,3. Thus, the emergency physician is faced with the difficult challenge of identifying those with ACS - a life-threatening disease - to treat them properly, and to discharge the others to suitable outpatient investigation and management.     

Utility of BNP measurement in the emergency room in patients with suspected unstable angina with a normal ECG

Unstable angina is a serious condition, difficult to diagnose in the emergency room. Clinical, electrocardiographic and biological signs (increased troponine) are not sensitive. The authors set out to assess whether measuring B natiuretic peptide in the emergency room was more sensitive for identifying symptomatic coronary lesions. One hundred and twenty patients admitted to the emergency room for chest pain compatible with the diagnosis of unstable angina and a normal ECG were included in this prospective study. All patients underwent coronary angiography during their hospital admission. The sensitivities of troponine at a threshold of 0.4 ng/ml and of brain natiuretic peptide (BNP) at a threshold of 10 pg/ml in this population were 66% and 92% respectively. The use of troponine and BNP together provided better results than troponine and BNP alone for the identification of patients with chest pain with significant coronary lesions.     

Comparison of the diagnostic accuracy of ischemia-modified albumin and echocardiography in patients with acute chest pain

BACKGROUND:

Several imaging tests and biomarkers have been proposed for the identification of patients with unstable angina among those presenting to the emergency department with acute chest pain. Preliminary data suggest that ischemia-modified albumin (IMA) may represent a potentially useful biomarker in these patients.

OBJECTIVE:

To compare IMA and echocardiography in excluding unstable angina in patients with acute chest pain.

METHODS:

Thirty-three patients (mean [± SD] age 59.8±10.8 years; 28 men) presenting to the emergency department with acute chest pain lasting <3 h suggestive of acute coronary syndrome, with normal or non-diagnostic electrocardiograms, and creatine kinase MB and troponin levels within the normal range, were included in the present study.

RESULTS:

After further diagnostic evaluation, five patients (15.2%) were diagnosed with unstable angina. The sensitivity, specificity, positive predictive value and negative predictive (NPV) value of echocardiography for diagnosing unstable angina was 60.0%, 89.3%, 50.0% and 92.6%, respectively. The area under the ROC curve for diagnosing unstable angina based on the serum IMA levels was 0.193 (95% CI 0.047 to 0.339; P<0.05). Based on ROC curve analysis, serum IMA levels ≥31.95 IU/mL yielded the optimal combination of sensitivity and specificity for diagnosing unstable angina. The sensitivity, specificity, positive predictive value and NPV of serum IMA levels ≥31.95 IU/mL for diagnosing unstable angina was 40.0%, 28.6%, 9.1% and 72.7%, respectively.

CONCLUSIONS:

Measurement of serum IMA levels appears to represent a useful tool for excluding unstable angina in patients presenting to the emergency department with acute chest pain. Moreover, IMA shows an NPV that is comparable with echocardiography.     

Prognostic value of predischarge dobutamine stress echocardiography in chest pain patients with a negative cardiac troponin T

OBJECTIVES: We prospectively studied the prognostic value of predischarge dobutamine stress echocardiography (DSE) in low-risk chest pain patients with a normal or nondiagnostic electrocardiogram (ECG) and a negative serial troponin T. BACKGROUND: Noninvasive stress testing is recommended before discharge or within 72 h in patients with low-risk chest pain. The prognostic value of immediate DSE has not been studied in a blinded, prospective fashion. METHODS: Patients presenting at the emergency room within 6 h of symptom onset and a normal or nondiagnostic ECG were eligible. Dobutamine stress echocardiography was performed after unstable coronary artery disease was ruled out by a standard rule-out protocol and a negative serial troponin T; the occurrence of any new wall motion abnormality was considered positive. Results were kept blinded. End points were cardiac death, myocardial infarction, rehospitalization for unstable angina or revascularization. RESULTS: In total, 377 patients were included. There were 2 deaths, 2 myocardial infarctions, 8 rehospitalization for unstable angina, and 10 revascularizations at six-month follow-up. The end points occurred in 8/26 (30.8%) patients with a positive versus 14/351 (4.0%) patients with a negative DSE (odds ratio, 10.7; 95% confidence interval, 4.0 to 28.8; p < 0.0001). By multivariate analysis, DSE remained a predictor of end points (p < 0.0001). CONCLUSIONS: A predischarge DSE had important, independent prognostic value in low-risk, troponin negative, chest pain patients.     

Usefulness of technetium-99m tetrofosmin single-photon emission computed tomography for short-term risk stratification in patients with acute chest pain in the emergency room

OBJECTIVES: High-risk patients with acute coronary syndrome are difficult to distinguish from low-risk patients with chest pain in the emergency room. Technetium-99m (99mTc) tetrofosmin single-photon emission computed tomography (SPECT) was investigated to exclude high-risk patients with chest pain in the emergency room. METHODS: 99mTc-tetrofosmin SPECT was evaluated using a four-point scoring system in 228 patients (144 men, 84 women, mean age 68 +/- 12 years) with chest pain. Negative was defined as the myocardial segments with a defect score (DS) of < 2. The patients were divided into two groups; the negative group with DS < 2 (n = 78) and the positive group with DS > or = 2 (n = 150). Cardiac events (cardiac death, acute myocardial infarction and refractory angina) were evaluated within 30 days of onset. ST-segment elevation or depression > or = 0.1 mV was defined as positive in electrocardiography. The results of SPECT were compared with those of electrocardiography, transthoracic echocardiography and serum cardiac markers (troponin T and creatine kinase-MB) in 95 patients. RESULTS: The negative group had very few cardiac events (three patients with refractory angina) (3.8%). The negative predictive value of cardiac events evaluated by electrocardiography was calculated as 83.1%, whereas the negative predictive value by SPECT was 96.2% (p < 0.01). In addition, the negative predictive value of acute myocardial infarction by SPECT was 100%. The negative predictive values of cardiac events evaluated by SPECT, electrocardiography, transthoracic echocardiography and serum cardiac markers were 95.8%, 81.5% (vs 99mTc-tetrofosmin; NS), 84.9% (NS) and 60.4% (p < 0.05), respectively. CONCLUSIONS: 99mTc-tetrofosmin SPECT is a useful method to exclude high-risk patients among patients with chest pain in the emergency room.     

Usefulness of clinical profiling and exercise testing in the prognostic assessment of patients admitted with chest pain but without high-risk criteria

INTRODUCTION AND OBJECTIVES: Few data are available on the outcome of patients admitted to hospital with suspected acute coronary syndrome who have no high-risk factors and who undergo exercise testing before discharge. Our objectives were to investigate outcomes in this group of patients and to determine whether clinical history-taking or exercise testing can help to predict outcome. PATIENTS AND METHOD: The study population comprised 449 patients admitted to hospital with chest pain suggestive of acute coronary syndrome. All were judged to be at a low risk of subsequent events (i.e., none had ischemic ECG changes or an elevation in troponin level). They underwent treadmill exercise testing before discharge, after an observation period of at least 12 hours. Exercise testing was performed after clinical evaluation based on an algorithm involving troponin-T level and resting ECG. The median follow-up duration was 479 days. The single combined endpoint was defined as cardiac death, or hospital admission for nonfatal acute myocardial infarction or unstable angina. RESULTS: Adverse events occurred in 44 (10%) of the 449 patients. A high event rate was associated with four clinical features (i.e., age > or =65 years, diabetes, previous acute myocardial infarction, and typical chest pain) and with a positive result on exercise testing. CONCLUSIONS: Adverse events after discharge are not infrequent in patients admitted to hospital with suspected acute coronary syndrome and a low risk profile. Both the patient's clinical characteristics and exercise test results should be taken into account in accurately determining prognosis.     

Behandlungspfad „Akutes Koronarsyndrom“

The clinical pathway "acute coronary syndrome" of the university hospital Marburg describes the guideline-conform and consented management of patients with ST-segment elevation infarct (STEMI), non-ST-segment elevation infarct (NSTEMI) and Troponin negative unstable angina. A 12-lead ECG recording is made and read in all patients within 10 minutes. All patients with STEMI undergo immediate revascularisation using primary percutanuous catheter intervention (PCI) after administration of basic medical therapy. Primary PCI is also used in all patients with NSTEMI, persistent chest pain, rhythm or hemodynamic instability. Patients with unstable angina, who became free of symptoms after application of basic medication, but who have additional risk factors undergo cardiac catheterisation within 48 hours. Acute myocardial infarction can be ruled out in patients with twofold negative cardiac troponin levels during 6-12 hours. In the absence of further symptoms, these patiens undergo differential diagnostic evaluation of cardiac and extracardiac causes of chest pain. The introduction of this clinical pathway 2 years ago, which was consented before by the hospital board and the clinical directors, has lead to a remarkable improvement in the clinical decision-making at the emergency room of the hospital and reduced the door to intervention time considerably.     

Cardiac emergency triage and therapeutic decisions using whole blood rapid troponin T test for patients with suspicious acute coronary syndrome

Emergency triage and therapeutic decisions using the recently developed whole blood rapid troponin T test were evaluated and compared with conventional electrocardiographic (ECG) diagnosis in a total of 155 patients with chest pain who visited 16 emergency outpatient clinics in the Tokyo metropolitan area. Thirty-seven patients (23.9%) had a final diagnosis of acute myocardial infarction or high-risk unstable angina requiring emergency coronary intervention and these events were defined as acute coronary syndrome. Diagnostic values using the second-generation rapid troponin T test were evaluated according to 3 time-windows in 85 patients. The sensitivity of the test was 10% for patients assessed within 3 h after the onset, 62.5% for 3-6 h after, and 75% for more than 6h, whereas conventional ECG diagnosis had 100% sensitivity at any time-window. In contrast, the specificity of the rapid troponin T test was 100%, 100%, and 97.4%, whereas that of conventional ECG diagnosis was 25%, 57.1%, and 42.2%, respectively for the 3 time-windows. The positive predictive value of ECG diagnosis was inferior to the rapid troponin T test, which reflected the prudent attitude of physicians taking ECG decisions as positive when myocardial ischemia was suspected. The diagnostic efficacy of the rapid troponin T test was remarkable in patients with the non-ST elevation type of acute coronary syndrome. A questionnaire survey on therapeutic decisions revealed that only 10% of Tokyo outpatient institutes performed prehospital thrombolytic therapy, 30-33% administered aspirin or nitrate, and 16.7% gave heparin. The rapid troponin T test is extremely useful for cardiac emergency triage and therapeutic decision making. There is a requirement for practical guidelines for the primary therapeutic decisions for patients with suspicious acute coronary syndrome.     

Results of Stent Supported Percutaneous Transluminal Coronary Angioplasty in Octogenarians With Coronary Artery Disease

Between January 1995 and July 1998, percutaneous transluminal coronary angioplasty was performed on 27 lesions in 24 octogenarians. Half of the patients were African American. Women comprised 67% of the study group. Patients with unstable angina and myocardial infarction constituted 54% of the cohort. Two-thirds of the patients (83%) had single vessel disease with predominant class A and B lesion complexity of the angioplasty site. Acute success rate was 92%. Stents were successfully placed in 11 subjects (46%). None had acute myocardial infarction, emergency coronary artery bypass surgery, or stroke as a complication of the procedure. One patient presenting with acute myocardial infarction complicated by cardiogenic shock, died. Significant bleeding complications requiring blood transfusions occurred in 17% of patients. Of the patients, 23 (96%) were discharged in a clinically stable condition. Follow up during a two year period was completed in 21 patients (88%). One patient died of cancer. Four subjects (19%) underwent repeat percutaneous transluminal coronary angioplasty. One other patient had recurrent chest pain requiring multiple hospitalizations. The remaining 16 patients (76%) remained free of recurrence of angina. We concluded that percutaneous transluminal coronary angioplasty with stent placement can be performed in octogenarians with a high rate of clinical and angiographic success with an acceptable range of morbidity and mortality, and favorable long term (two year) outcome.     

Continuous 12-lead electrocardiographic monitoring in an emergency department chest pain unit: an assessment of potential clinical effect

STUDY OBJECTIVES: Continuous 12-lead serial ECG monitoring has been proposed to assist in the evaluation of patients with acute coronary syndrome and nondiagnostic ECG in an emergency department chest pain unit. However, the ability of serial ECG to detect acute coronary syndrome and its benefit in addition to a standard protocol has not been established. We evaluate the ability of continuous 12-lead ECG to detect acute coronary syndrome, assess the incremental benefit of the serial ECG in association with a set protocol in an ED chest pain unit, and evaluate whether serial ECG changes could be considered as prognostic factors. METHODS: Patients who met Agency for Health Care Policy and Research guidelines for intermediate risk for short-term cardiovascular event unstable angina were prospectively studied in the chest pain unit. Patients were monitored with the Mortara Instruments ELI 100 STM continuous 12-lead ECG system with ST-segment analysis. ST-segment changes of greater than 100 microV in 2 or more contiguous leads or greater than 200 microV in 1 lead were considered positive. Data were compared with serial serum cardiac markers, cardiac function study results, angiographic results, and 30-day outcome results. RESULTS: One hundred nineteen patients had serial ECG applied. The median duration of monitoring was 4.2 hours. Forty patients were given a diagnosis of acute coronary syndrome. Chest pain unit protocol detected 52 patients, and 23 were given a diagnosis of acute coronary syndrome (sensitivity 58%; specificity 63%). Sixteen patients had ST-segment changes of greater than 100 microV or greater than 200 microV, and 9 were given a diagnosis of acute coronary syndrome. The addition of the serial ECG to the chest pain unit protocol increased the sensitivity to 65% and decreased the specificity to 58%. Two patients with ST-segment changes but none without ST-segment changes had an adverse cardiac event, yielding a sensitivity of 100% and a specificity of 88%. CONCLUSION: Serial ECG is of limited value in the diagnostic evaluation of intermediate-risk patients managed in the chest pain unit with a standard protocol. However, when ST-segment changes are present, they indicate an increased likelihood for an adverse cardiac event.     

Usefulness of ST-segment changes in ≥2 leads on the emergency room electrocardiogram in either unstable angina pectoris or non-Q-wave myocardial infarction in predicting outcome

To determine the reliability of the admission electrocardiogram in predicting outcome in patients hospitalized for chest pain at rest, 90 patients were randomized into a trial of aspirin versus heparin in unstable angina or non-Q-wave myocardial infarction, and prospectively followed for 3 months. The emergency room admission electrocardiogram was analyzed for ST-segment deviation ≥1 mm/lead and T-wave changes. Unfavorable outcomes were recurrent ischemic pain, myocardial infarction and coronary revascularization with angioplasty or surgery. In patients who underwent coronary arteriography, a myocardium in jeopardy score ranging from 0 to 10 was assigned, based on the number of vessels with a diameter stenosis ≥70% and the location of the stenoses. Considering all 90 patients, an admission electrocardiogram with ST-segment deviation in ≥2 leads had a positive predictive value for adverse clinical events of 79% and a negative predictive value of 64%. In the subset of patients without left ventricular hypertrophy and whose admission electrocardiograms were recorded during chest pain (62 of 90), the positive predictive value of ST deviation in ≥2 leads improved to 89% and the negative value to 72%. Of the 62 patients, 53 underwent coronary arteriography. There was a positive linear correlation between the total number of leads with ST-segment deviation and the myocardium in jeopardy score (r = 0.80, p < 0.001). In patients with unstable angina or non-Q-wave myocardial infarction, an admission electrocardiogram recorded during pain and revealing ST-segment changes in ≥2 leads is by itself a reliable predictor of major clinical events. The total number of leads with ST changes predicts the extent of myocardium in jeopardy.     

C-reactive protein as a marker for acute coronary syndromes

BACKGROUND: For several years, acute coronary syndromes have been perceivedas causing the most hospital admissions, and even hospital mortality.The syndrome of unstable angina frequently progresses to acutemyocardial infarction but its pathogenesis is poorly understood,and prognosis determination is still problematic. We testedthe hypothesis that measurement of the C-reactive protein inpatients admitted for chest pain could be a marker for acutecoronary syndromes. METHODS AND RESULTS: We studied 110 patients admitted with suspected ischaemic heartdisease, but without elevated serum creatine-kinase levels atthe time of hospital admission. Patients were subsequently dividedinto two groups based on their final diagnosis: group 1 comprisedpatients with unstable angina; group 2 patients with acute myocardialinfarction. We measured the C-reactive protein at the time ofhospital admission. The concentration of C-reactive proteinwas elevated in 59% of the patients with a final diagnosis ofacute myocardial infarction, and in 5% of the patients witha final diagnosis of unstable angina, (P<0·001). CONCLUSION: This study indicates that C-reactive protein levels measuredat the time of admission in patients with suspected ischaemicheart disease could be a marker for acute coronary syndromes,and helpful in identifying patients at high risk for acute myocardialinfarction. Measurement of C-reactive protein may have practicalclinical significance in the management of patients hospitalizedfor suspected acute coronary syndromes.