Biochemical Markers Of Myocardial Necrosis Research Articles

TYPE 2 MYOCARDIAL INFARCTION: MODERN DIAGNOSTIC TECHNIQUES AND TREATMENT

HighlightsPatients with type 2 myocardial infarction have a more favorable course of the disease in the long-term postinfarction period compared with patients with type 1 myocardial infarction. We have determined the differences in clinical and anamnestic characteristics of patients with type 1 and type 2 MI. AbstractAim. To determine the prevalence of patients with type 2 myocardial infarction (MI) and their features in clinical practice.Methods. The prospective study involved 204 patients with acute coronary syndrome (ACS). The inclusion criteria were as follows: diagnosed ACS at admission followed by a confirmed MI during the inpatient period according to the Fourth Universal definition of MI. The following parameters were analyzed: anthropometric parameters, clinical and anamnestic characteristics, results of laboratory tests, biochemical markers of myocardial necrosis, results of instrumental diagnostics and coronary angiography. A follow-up telephone survey was carried out a year after ACS, noting the following endpoints: repeated coronary events, death, repeated hospitalizations, adherence to medical recommendations, medication taken by the patient.Results. Type 2 MI was diagnosed in 22 (10.8%) patients. The results of coronary angiography revealed either the absence of coronary artery (CA) stenosis or the presence of stenosis of less than 50% without indications of thrombosis in 16 (72.7%) of those patients. Chronic total occlusion of a non-infarct-related artery was found in 6 (27.3%) patients. Patients with type 2 MI were comparable in age with patients with type 1 MI. The group of patients with type 2 MI included more women (p = 0.029), fewer smokers (p = 0.037) and more cases of atrial fibrillation (AF) (p = 0.003) compared to patients with type 1 MI. The factors that were associated with type 2 MI were as follows: sinus tachycardia in 3 (13.6%) patients, paroxysmal atrial flutter or AF with ventricular tachysystole in 4 patients (18.2%).Conclusion. Patients with type 1 MI presented with a less favorable course of the disease: we noted higher number of recurrent MI and deaths one year after the index event compared with patients with type 2 MI. The group of patients with type 2 MI consisted mostly of women, fewer smokers and patients with dyslipidemia, as well as a more frequent indication of AF compared with patients with type 1 MI.

Acute coronary syndrome as a current issue of pediatric cardiology. Outcomes and prognosis: Clinical case

Background. Acute coronary syndrome is widespread in the adult population and has clear diagnostic criteria. In pediatric practice, this pathology is rare, and often implies difficulties in diagnosis. Case description. A 16-year-old male with negative paternal history, hypercholesterolemia, dyslipidemia, and excessive body weight developed myocardial infarction on the background of acute tonsillitis. In the onset of the disease, the adolescent demonstrated clinical signs of acute respiratory infection and coronary spasm. Electrocardiogram revealed ST segment elevation above the baseline in leads I, II, III, aVF, V4–V6 and biochemical markers of myocardial necrosis. Echocardiography revealed signs of focal hypokinesis of the left ventricle, newly detected degree 2 mitral regurgitation. Percutaneous coronary angiography revealed no signs of coronary artery stenosis. The patient received conventional medical treatment of acute myocardial infarction as well as antibacterial therapy. He was discharged in satisfactory condition. After 1 year of follow-up after the myocardial infarction the patient showed no pathologic changes both on stress-echocardiography and electrocardiogram. Three-year catamnesis appeared to be favorable. Conclusion. The presented clinical case demonstrates the individual mechanism of acute coronary syndrome development in children. Pediatricians should be aware of the risk of developing acute coronary syndrome against the background of infectious pathology.

249 Prognostic role of diagnostic criteria of acute myocardial infarction

Abstract Aims The term acute myocardial infarction (AMI) reflects cell death of cardiac myocytes caused by ischaemia. The Fourth Universal Definition of Myocardial Infarction (UDMI) defined AMI by a typical rise and fall in the level of biochemical markers of myocardial necrosis together with criteria of myocardial ischaemia. However, the prognostic role of each single diagnostic criteria has never been explored. To evaluate the prognostic role of the different diagnostic criteria of AMI according to the Fourth UDMI. Methods and results We enrolled all consecutive patients with AMI admitted from 2016 to 2019. We used a combination of criteria, according to the current ESC guidelines, to meet the diagnosis, namely the detection of an increase and/or decrease of high-sensitivity cardiac troponin I, with at least one value above the 99th percentile of the upper reference limit and at least one of the following: symptoms of ischaemia; ECG changes (new ST-T changes or new left bundle branch block); development of pathological Q waves in the ECG; imaging evidence of new loss of viable myocardium or new regional wall motion abnormality, in our study evaluated by transthoracic echocardiogram. All-cause mortality and a composite endpoint of all-cause mortality, re-hospitalization for heart failure, and myocardial re-infarction were collected. The predictive value of diagnostic criteria alone and its association were evaluated using Kaplan–Meier survival curves and subsequent Cox-regression analysis to find independent predictors of adverse events. 2386 patients were evaluated. The median follow-up time was 23.3 ± 14.5 months. The total number of events was 703 (29.5%). Kaplan–Meier curves showed that major adverse cardiac events (MACEs) were statistically different depending on the diagnostic criteria of AMI at admission. Particularly, clinical criteria alone showed a better predictive value (P < 0.001) than other diagnostic AMI criteria. Multivariable Cox-regression model demonstrated that clinical criteria were the independent predictor of good prognosis in patients with AMI (HR = 0.43; 95% CI: 0.28–0.67; P < 0.001). Conversely, the other diagnostic criteria (electrocardiographic and echocardiographic) and the combination of all diagnostic criteria were not independent prognostic factors of MACEs (HR = 1.1; 95% CI: 0.6–2.4, P = 0.6; HR = 1.1; 95% CI: 0.7–1.9, P = 0.6; HR = 0.9; 95% CI: 0.7–1.0, P = 0.2, respectively). Conclusions Our data suggest that the prognosis is considerably better among patients with a diagnosis of AMI if clinical criteria alone are present at admission. We also demonstrated that clinical criteria are a strong prognostic predictor of good outcomes in patients with AMI. We hypothesize that the absence of electrocardiographic and echocardiographic alterations could indirectly indicate a smaller infarct sizes that contribute to patients’ outcome.

Prognostic role of diagnostic criteria of acute myocardial infarction

Abstract Background The term acute myocardial infarction (AMI) reflects cell death of cardiac myocytes caused by ischaemia. The Fourth Universal Definition of Myocardial Infarction (UDMI) defined AMI by a typical rise and fall in the level of biochemical markers of myocardial necrosis together with criteria of myocardial ischaemia. However, the prognostic role of each single diagnostic criteria has never been explored. Purpose To evaluate the prognostic role of the different diagnostic criteria of AMI according to the Fourth UDMI. Methods We enrolled all consecutive patients with AMI admitted from 2016 to 2019. We used a combination of criteria, according to the current ESC guidelines, to meet the diagnosis, namely the detection of an increase and/or decrease of high-sensitivity cardiac troponin I, with at least one value above the 99th percentile of the upper reference limit and at least one of the following: symptoms of ischaemia; ECG changes (new ST-T changes or new LBBB); development of pathological Q waves in the ECG; imaging evidence of new loss of viable myocardium or new regional wall motion abnormality, in our study evaluated by transthoracic echocardiogram. All-cause mortality and a composite endpoint of all-cause mortality, re-hospitalization for heart failure and myocardial re-infarction were collected. The predictive value of diagnostic criteria alone and its association were evaluated using Kaplan-Meier survival curves and subsequent Cox-regression analysis to find independent predictors of adverse events. Results 2386 patients were evaluated. The median follow-up time was 23.3±14.5 months. The total number of events was 703 (29.3%). Kaplan-Meier curves showed that major adverse cardiac events (MACE) were statistically different depending on the diagnostic criteria of AMI at admission. Particularly, clinical criteria alone showed a better predictive value (p<0.001) than other diagnostic AMI criteria. Multivariable Cox-regression model demonstrated that clinical criteria was the independent predictor of good prognosis in patients with AMI (HR=0.43; CI 95% 0.28–0.67; p<0.001). Conversely, the others diagnostic criteria (electrocardiographic and echocardiographic) and the combination of all diagnostic criteria were not independent prognostic factors of MACE (HR=1.1 CI 95% 0.6–2.4, p=0.6; HR=1.1 CI 95% 0.7–1.2, p=0.6; HR=0.9 CI 95% 0.7–1.0, p=0.8 respectively). Conclusions Our data suggest that the prognosis is considerably better among patients with a diagnosis of AMI if clinical criteria alone are present at admission. We also demonstrated that clinical criteria are a strong prognostic predictor of good outcomes in patients with AMI. We hypothesize that the absence of electrocardiographic and echocardiographic alterations could indirectly indicate a smaller infarct sizes that contribute to patients' outcome. Funding Acknowledgement Type of funding sources: Public hospital(s). Main funding source(s): None

Difficulties of diagnostics of acute myocardial infarction in elderly and senile patients and their influence on management in the acute period of disease

Aim. To study the features of disease progress and approaches to the diagnostics of acute myocardial infarction (MI) among elderly and senile patients and their influence on the management in the acute period of disease.Materials and methods. The study was performed using the WHO program “Register of acute myocardial infarction” (Tomsk). The study included 410 patients (60 years and older), who had acute MI. The study group is represented by a comparable number of men (n=212) and women (n=198). The mean age of patients was 71 (66; 77) years (women are 5 years older than men (p<0,001)). Statistical processing was performed using the program Statistica V10.0.Results. Most of the patients had history comorbid pathology. In one in five patients (17,8%), the disease had an atypical manifestations, which in 41% of cases was represented by the asymptomatic form. Atypical manifestation of MI lengthened the prehospital phase of medical care due to a longer time before the first medical contact (p=0,005), as well as a late help-seeking (120 [49; 311,5] minutes). In 28% of patients, the level of creatine kinase-MB remained normal, and the indicator of troponin I exceeded the maximum values only in half of the cases. One fifth of the patients underwent acute MI treatment in non-core hospitals, which resulted in a low frequency of intervention (38%) and increasing by 2 times the chance of death within 5 years. The level of hospital mortality from acute MI in elderly patients in noncore hospitals was 3 times higher than in specialized departments (p<0,001).Conclusion. Difficulties in diagnostics of MI in patients of older age groups is caused by the prevalence of comorbid pathology, an atypical manifestations of the disease and low information content of biochemical markers of myocardial necrosis. It leads to an increase in time delays at the prehospital phase and frequent hospitalization of patients in non-core hospitals, making it impossible for them to receive timely, preferred therapy.

Unusual case of myocardial injury induced by Escherichia coli sepsis

The typical symptoms and signs of myocardial infarction are well known. Alterations in electrocardiogram (ECG), echocardiography or biochemical markers of myocardial necrosis are usually helpful to confirm the diagnosis. Some of these features, however, also occur in myocarditis, which is a potential differential diagnosis. We describe an unusual case of bacterial sepsis due to Escherichia coli that caused myocardial damage (myocarditis) with ECG changes mimicking acute myocardial infarction. The possible pathophysiological mechanisms of myocardial injury in sepsis are also reviewed.

AVALIAÇÃO DOS MARCADORES DE LESÃO MIOCÁRDICA SOLICITADOS EM HOSPITAL PAULISTA

A mensuração dos marcadores bioquímicos de necrose miocárdica é essencial para diagnosticar precocemente o Infarto Agudo do Miocárdio e garantir um melhor prognóstico ao paciente. No entanto, cada marcador possui um perfil, que deve se adequar às características do quadro clínico que está sendo avaliado. Sendo assim, o objetivo do presente trabalho foi verificar o perfil de solicitações de marcadores cardíacos séricos junto ao laboratório clínico do Hospital Heliópolis, e discutir as implicações de tais escolhas. Por meio da verificação dos mapas de resultados do laboratório, foi feito um levantamento dos marcadores bioquímicos de lesão miocárdica solicitados, em um período de três meses, de pacientes admitidos no pronto socorro com sintomas sugestivos de um evento cardíaco isquêmico. Do total de 2242 exames provenientes de 1084 pacientes, 47% eram para CK total, 43% para CK-MB e 10% para troponinas, não havendo solicitações de dosagem de mioglobina durante o período estudado. Do total de exames solicitados e alterados, a maioria referiu-se a pacientes do gênero masculino. O presente artigo sugere que no momento da admissão do paciente no serviço de emergência, haja a solicitação combinada da mioglobina e um marcador mais específico de necrose miocárdica (CK-MB) para a exclusão precoce de um infarto do miocárdio. Isto seria, além de eficaz para o diagnóstico, uma maneira mais viável financeiramente. Neste contexto, uma atenção especial deveria ser dada às mulheres atendidas com sintomas isquêmicos, tendo em vista a alta taxa de mortalidade a elas associada.

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Introduction: Elevated levels of biochemical markers of myocardial necrosis have been associated with worsened outcomes in critically ill patients, but there are few data on focusing patients with severe pneumonia. We investigated elevated cardiac troponin I (cTnI) levels and their relationship with outcomes in patients who hospitalized for severe pneumonia to intensive care unit (ICU). Methods: From February 2011 to February 2013, Patients who admitted to medical ICU with severe pneumonia and availability of cTnI within 24 hours were included at a tertiary care academic medical center. Patients with evidence of ACS were excluded. A cTnI level> 0.034ng/mL was considered positive. Results: 152 patients (community acquired pneumonia (39.5%), health care associated pneumonia (40.8 %), and hospital acquired pneumonia (19.7%)) were included, 48 of whom died (31.6%). 88 patients had detectable cTnI levels (58%) and median cTnI level was 0.049 ng/mL. Patients with increased cTnI levels had higher in-ICU mortality (38.6% vs. 21.9%, p=0.028). The association between increasing cTnI and mortality remained significant after adjustment in a multivariate model (HRadj =1.427, 95% CI 1.032–1.973, p=0.031). Conclusions: Increased cInI level was significant independent predictor of in ICU mortality in hospitalized patients with severe pneumonia and no other cause for an increased cTnI level.

Prognostic Significance of Elevated Cardiac Troponin-T Levels in Acute Respiratory Distress Syndrome Patients

BackgroundElevated levels of biochemical markers of myocardial necrosis have been associated with worsened outcomes in Acute Respiratory Distress Syndrome (ARDS), but there are few prospective data on this relationship. We investigated elevated cardiac troponin T (cTnT) levels and their relationship with outcome in patients with ARDS.MethodsA prospective cohort study of patients with ARDS was conducted at a tertiary-care academic medical center. Patients had blood taken within 48 hours of ARDS onset and assayed for cTnT. Patients were followed for the outcomes of 60-day mortality, number of organ failures, and days free of mechanical ventilation. Echocardiographic and electrocardiographic (ECG) data were analyzed for signs of myocardial ischemia, infarction, or other myocardial dysfunction.Results177 patients were enrolled, 70 of whom died (40%). 119 patients had detectable cTnT levels (67%). Median cTnT level was 0.03 ng/mL, IQR 0–0.10 ng/mL, and levels were higher among non-survivors (P = .008). Increasing cTnT level was significantly associated with increasing mortality (P = .008). The association between increasing cTnT level and mortality remained significant after adjustment in a multivariate model (HRadj = 1.45, 95% CI 1.17–1.81, P = .001). Elevated cTnT level was also associated with increased number of organ failures (P = .002), decreased number of days free of mechanical ventilation (P = .03), echocardiographic wall motion abnormalities (P = 0.001), and severity of tricuspid regurgitation (P = .04). There was no association between ECG findings of myocardial ischemia or infarction and elevated cTnT.ConclusionsElevated cTnT levels are common in patients with ARDS, and are associated with worsened clinical outcomes and certain echocardiographic abnormalities. No association was seen between cTnT levels and ECG evidence of coronary ischemia.

CardioPulse Articles

Patients with an acute coronary syndrome (ACS) and ST-segment elevation (STEMI) benefit from immediate revascularization by percutaneous coronary intervention (PCI) or, if such is not readily available, from thrombolytic therapy. Furthermore, some of those without such electrocardiographic (ECG) findings benefit from early revascularization. Therefore, patients with a possible ACS should be assessed immediately to confirm the diagnosis, to initiate medical therapy, and to verify whether ECG findings and subsequent biochemical markers of myocardial necrosis (preferable troponin T or I) warrant invasive therapy. In order to provide a rapid response, different methods of working have been developed: pre-hospital diagnosis of STEMI, chest pain clinics, and fast track at the emergency unit. When an ambulance is called by the patient, his/her relatives or a physician, a complete 12-lead ECG should be taken to decide whether an ACS with ST elevation is present. This ECG may be interpreted by a physician if present on the ambulance, or by an onsite computer system, as was introduced in Rotterdam in the 1980s. Alternatively, the ECG may be transmitted to a hospital for interpretation by a physician. Patients with ST elevation can be immediately transferred to a hospital with PCI facilities or may receive immediate, pre-hospital thrombolytic therapy. A chest pain unit, adjacent to the general emergency unit, was introduced in Amsterdam in the 1980s. This principle was subsequently adopted by other hospitals in The Netherlands and abroad. Patients with chest pain and a possible ACS are assessed in this unit and can stay in the chest pain unit for a maximum of a few hours, until a final diagnosis is made, based on ECG, repeat troponin measurements, or other markers of myocardial injury or other investigations as appropriate. Once a diagnosis is confirmed, the patient is either admitted to the appropriate hospital ward or discharged. The chest pain unit is supervised by a cardiologist and managed by a cardiology resident. In many hospitals worldwide, patients are assessed at the general emergency unit in a hospital. In the emergency unit, a patient may be seen by an emergency physician, an internist, or a cardiologist. Several studies have shown that in patients with ACS, optimal treatment according to guidelines is best provided if a cardiologist is in charge. Nevertheless, other physicians can assume responsibility provided that they comply with the same guidelines, avoiding unnecessary delay of treatment in those patients with evolving myocardial infarction (STEMI). Such delay may be avoided when the nurses are instructed to record an ECG immediately upon arrival of the patient and call for attention if ST elevation or ST depression is apparent. It should be appreciated that patients with STEMI are a minority among those presenting with chest pain or similar symptoms. Accordingly, it is a challenge to differentiate those patients requiring immediate PCI from those with other diagnoses in whom, generally, a longer observation period is warranted. The protocol of the emergency department is crucial to guarantee optimal treatment of patients with chest pain. It should include registration of the admission diagnoses of all patients seen at the unit, with the time from entry to ECG recording and diagnosis. A regular review of such registry will help to optimize patient management.

False positive or true positive troponin in patients presenting with chest pain but 'normal' coronary arteries: lessons from cardiac MRI

Cardiac magnetic resonance imaging (MRI), particularly when enhanced with commonly available gadolinium-based contrast agents, is a powerful clinical tool for characterizing myocardial abnormalities. One of the best-known applications of this relatively new technology has been the detection of myocardial infarction. It is also possible to image myocardial scarring or fibrosis in other disease states such as myocarditis and infiltrative cardiomyopathies. Assomull et al. 1 from the Royal Brompton Hospital document the adjunctive diagnostic value of late gadolinium enhancement imaging in patients who present with chest pain, elevated troponin but unexpectedly ‘normal’ appearing coronary angiograms. The introduction of troponin assays revolutionized the diagnosis of acute myocardial infarction. This was largely based on the high sensitivity and specificity for acute myocardial injury. Elevated troponin was associated with adverse prognosis before we came to a consensus that it must be a marker of cardiac necrosis. On the basis of this work and a much wider range of literature than can be quoted in this brief article, the very definition of myocardial infarction was revised in 2000.2 The revised definition of myocardial infarction required either pathological evidence of acute myocardial infarction or a new set of clinical criteria based largely on serum markers of myocardial necrosis. Acute myocardial infarction can be diagnosed by a typical rise and gradual fall (troponin) or more rapid rise and fall (CK-MB) of biochemical markers of myocardial necrosis with at least one of the following: (i) ischaemic symptoms, (ii) development of pathological q-waves on ECG, (iii) ECG changes indicative of ischaemia (ST-elevation or ST-depression), or (iv) percutaneous coronary intervention.2 Although overall a substantial advance in our understanding … Corresponding author. Tel: +1 301 496 3658; fax: +1 301 402 2389. E-mail address : araia{at}nih.gov

Myocardial infarction: contemporary management strategies

Myocardial infarction (MI) is a common clinical diagnosis, associated with significant morbidity and mortality, not only in the short term, but also years following the index event. A more complete understanding of the pathophysiology of MI has ushered the era of multipronged treatment approach, with a combination of goal-directed revascularization, a broad adjunctive pharmacological therapy and aggressive secondary prevention measures. The goals of this article are to review the basic pathophysiological processes, which lead up to a clinical diagnosis of MI, to highlight the essential elements of clinical presentation and to summarize the evidence for comprehensive therapy. Emphasis has been placed on the choice of primary reperfusion therapy for ST-elevation MI, on risk-stratification of patients with non-ST elevation MI, and on rationale behind the selection of anti-ischaemic and antithrombotic therapy. Finally, evidence-based approach to secondary prevention is outlined.

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Diagnostic Applications of Natriuretic Peptides in Ischemic Heart Disease

Early assessment of patients who have symptoms suggestive of an acute coronary syndrome (ACS) remains a challenge considering the heterogeneity of underlying pathologies and clinical outcomes. The purpose of the early evaluation of these patients is threefold: first, to diagnose or exclude acute myocardial infarction (AMI) second, to identify patients at different risks for future cardiac events; and third, to be able to select appropriate treatment. Currently the initial assessment of these patients is based on the patient’s history, clinical findings, ECG data, and serial testing of biochemical markers of myocardial necrosis, preferably troponin T or I. In the last few years, an increasing number of studies have evaluated the addition of the natriuretic peptides, NT-proBNP and BNP, in the diagnostic and prognostic arsenal for assessment of patients who have a suspected ACS. The studies of the value of natriuretic peptides have also been extended to patients who have stable angina pectoris for detection of significant coronary artery disease (CAD) and for assessment of the long-term risk. NT-proBNP and BNP in the different forms of ischemic heart disease The prognostic value of NT-proBNP and BNP has been evaluated in the full spectrum of ischemic heart disease in a large number of studies. It is striking that the increased mortality associated with elevation of NT-proBNP or BNP is of a similar degree, regardless of type of presentation of the ischemic heart disease.

European Society of Cardiology educational website

ESCed is an educational website developed by the European Society of Cardiology. The site is currently free and access is obtained after registering with the website. The educational content is based on the format of case presentations. The site presently has 18 modules grouped into seven categories: acute coronary syndromes, chronic ischaemic heart disease, heart failure, arrhythmias, hypertension, valve disease and coronary heart disease risk factors. The website states that more modules are under development. Each module starts with a short case history followed by a series of multiple-choice questions. The questions progress in chronological order and ask the user to select investigations or interventions at critical points as the patient's clinical history unfolds. The time since symptom onset and/or the time since admission is listed on each question page. At the top of each question page are icons that display the medical history, clinical notes and test results. Images are provided for tests such as electrocardiography, echocardiography, angiography or computed tomography. Short video clips can also be viewed for echocardiography and angiography. On the answer page a bar chart displays how often each option presented in the question has been selected by previous users. Comments are made regarding each of the options and references are cited. Selecting a reference displays the abstract of that article. When reference is made to a European Society of Cardiology guideline, a link is provided to view the full text document. Most pages have a box with further information related to the case being presented; for example, 'other causes of dyspnoea' in a case presenting with dyspnoea, 'biochemical markers of myocardial necrosis' in a patient presenting with chest pain or 'CABG versus medical therapy' in a patient with chronic stable angina. All drugs mentioned in the modules are highlighted, and selecting a drug opens a pop-up box with information about the drug, including indications, formulation, cautions, contraindications, side effects, dose and drug interactions. This information is taken from the March 2002 issue of British National Formulary. Some of the modules contain logos of pharmaceutical companies. However, the exact role of and the extent of the involvement of these companies has not been declared on the website. A few modules have received support from the European Union. ESCed is accredited for continuing medical education by the European Board for Accreditation in Cardiology, which works in cooperation with the European Accreditation Council for Continuing Medical Education. At the end of each module the user can obtain 1 hour of continuing medical education credit. Entering a keyword or phrase in the search engine displays the relevant case histories and the cited references. The site also has a discussion forum that currently has eight topics, including aspirin in patients with acute coronary syndrome and peptic ulcer, and haemodynamic instability in atrial fibrillation. However, very few comments have so far been posted. Overall, I found the cases to be well presented with a wealth of related information presented in each module. I think medical students and residents will obtain great educational value from visiting the site. In addition to physicians with an interest in cardiology, the site should also be of interest to emergency room physicians, intensivists and general medicine physicians. The number of topics covered is presently limited, but the site can only get better as more modules are added.

Evaluation of patients with suspected acute coronary syndromes in the emergency department.

Patients complaining of chest pain (CP) who visit the emergency department (ED) represent the second cause of consultation in this department, and 20-30% of hospital admissions for medical reasons. These patients form a somewhat heterogeneous group with many different aetiologies and degrees of severity. In this setting, the clinical objectives include the prompt identification of patients with acute coronary syndromes (ACSs), the prompt evaluation of the immediate risk (i.e., initial risk stratification) of cardiovascular complications in order to tailor the treatment for each individual patient and to make the best use of hospital resources, and the prompt identification of patients with other potentially severe diseases. The diagnosis of ACS in patients coming to the ED for CP or any equivalent angina is one of the most difficult diagnostic challenges facing physicians in the ED. The correct diagnosis and risk stratification of these patients has clinical consequences, as well as very important legal and economic implications. The only methodology with a clear clinical impact on diagnosis, risk stratification and initial management is clinical evaluation based on data obtained by questioning the patient, carrying out a physical examination, and interpreting the results of a standard 12-lead electrocardiogram (ECG). Nevertheless, its combined diagnostic efficiency for ACS is imperfect and additional strategies are emerging which include serial ECG, the detection of serum biochemical markers of myocardial necrosis, exercise testing, and radionuclide myocardial perfusion imaging.

Comparison of the 80-lead body surface map to physician and to 12-lead electrocardiogram in detection of acute myocardial infarction

Diagnosis of non–ST-elevation acute myocardial infarction (AMI) by a 12-lead electrocardiogram has poor sensitivity and specificity and, therefore, relies on biochemical markers of myocardial necrosis, which can only be reliably detected within 14 to 16 hours from symptom onset. The body surface map (BSM) improves AMI detection but is limited by its interpretation by inexperienced medical staff. To facilitate interpretation, an automated BSM algorithm was developed and is evaluated in this study. One hundred three patients with ischemic-type chest pain were recruited for this study from December 2001 to April 2002. A 12-lead electrocardiogram (Marquette Mac 5K) and BSM (PRIME-ECG) were recorded at initial presentation, and cardiac troponin I and/or creatine kinase-MB levels measured at 12 hours after symptom onset. The admitting physician’s 12-lead electrocardiographic (ECG) interpretation, 12-lead ECG algorithm (Marquette 12 SL V233) diagnosis, and BSM algorithm diagnosis were documented for each patient. AMI, defined by elevation of troponin I to >1 μg/L and/or creatine kinase-MB to >25U/L, occurred in 53 patients. The admitting physician diagnosed 24 patients with AMI (sensitivity 45%, specificity 94%), the 12-lead ECG algorithm diagnosed 17 patients with AMI (sensitivity 32%, specificity 98%), and the BSM algorithm diagnosed 34 patients with AMI (sensitivity 64%, specificity 94%). The BSM algorithm improved the diagnostic sensitivity by 2.0 (p <0.001) and 1.4 (p = 0.002) compared with the 12-lead ECG algorithm or the admitting physician, respectively. There was no significant difference in specificity. Thus, the BSM algorithm improves detection of AMI compared with the 12-lead ECG algorithm or physician’s 12-lead ECG interpretation.

Failed reperfusion after thrombolytic therapy: Recognition and management

Background: Failed reperfusion after thrombolysis occurs in as many as 30% of patients with acute myocardial infarction (MI). Furthermore, some patients have incomplete tissue perfusion despite reperfusion of the infarct-related artery. Close assessment of the efficacy of thrombolytic administration in people with evolving acute MI is necessary, particularly with regard to myocardial perfusion status, because some patients may benefit from incremental pharmacologic or invasive reperfusion strategies. Purpose and Method: This article reviews a number of strategies to assess infarct-related artery patency and myocardial tissue perfusion. These include coronary angiography, continuous ST-segment monitoring, serial electrocardiography, obtaining serial serum biochemical markers of myocardial necrosis, monitoring for reperfusion arrhythmias, and assessment of changes in chest pain intensity. Conclusion: The early detection of failed reperfusion is critical if incremental strategies to enhance myocardial salvage are to be considered. Continuous ST-segment monitoring is a relatively inexpensive, reliable, and accurate tool for assessing real-time myocardial perfusion. (Heart Lung® 2002;31:113-21.)

Medical therapy of unstable angina and non–q-wave myocardial infarction

Management of acute coronary syndromes has been the focus of increased interest in recent years. This has come about with the recognition that the majority of patients who present to the hospital with chest pain have unstable angina or non–Q-wave myocardial infarction (MI). Further, sensitive biochemical markers of myocardial necrosis, such as troponin and creatine kinase, have improved early diagnosis. Markers of inflammation such as C-reactive protein (CRP), although not in wide clinical practice, may provide an early and important marker of prognosis. The current approach to management of acute coronary syndromes is careful risk stratification so as to select appropriate medical therapies and to guide the clinician to appropriate interventions such as angiography or percutaneous coronary intervention (PCI). Established therapies such as aspirin, heparin, intravenous nitrates, and, in selected patients, β blockers or calcium antagonists, are being used concomitantly with, or are being supplanted by, newer therapies such as low-molecular-weight heparins and glycoprotein IIb/IIIa inhibitors. The role of hydroxymethyl glutaryl coenzyme A reductase inhibitors (statins) in patients with acute coronary syndromes is being investigated and shows promise.

Myocardial infarction redefined—a consensus document of The Joint European Society of Cardiology/American College of Cardiology committee for the redefinition of myocardial infarction: The Joint European Society of Cardiology/ American College of Cardiology Committee

Definition of MI. Criteria for acute, evolving or recent MI. Either one of the following criteria satisfies the diagnosis for an acute, evolving or recent MI: 1) Typical rise and gradual fall (troponin) or more rapid rise and fall (CK-MB) of biochemical markers of myocardial necrosis with at least one of the following: a) ischemic symptoms; b) development of pathologic Qwaves on the ECG; c) ECG changes indicative of ischemia (ST segment elevation or depression); or d) coronary artery intervention (e.g., coronary angioplasty). 2) Pathologic findings of an acute MI. Criteria for established MI. Any one of the following criteria satisfies the diagnosis for established MI: 1) Development of new pathologic Q waves on serial ECGs. The patient may or may not remember previous symptoms. Biochemical markers of myocardial necrosis may have normalized, depending on the length of time that has passed since the infarct developed. 2) Pathologic findings of a healed or healing MI.