Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0008031 (chest pain)
 17,248 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Troponin T is a structurally bound protein found in striated muscle cells. We tested concentrations of its cardiac-specific isotype in peripheral venous blood samples serially drawn from 72 patients with confirmed myocardial infarction. Fifty-nine patients received thrombolytic treatment with intravenous streptokinase, urokinase, or recombinant tissue-type plasminogen activator; because of contraindications, the remaining 13 patients did not. Concentrations of troponin T in plasma, measured by an enzyme-linked immunosorbent assay, started increasing within a few hours after the onset of symptoms (median, 4 h; range, 1-10 h). The sensitivity of troponin T for detecting myocardial infarction was 100% from 10 to 120 h after the onset of symptoms; sensitivity on the seventh day after admission was 84%. Concentrations were increased for up to three weeks in some patients with late or high peak values. Successful reperfusion in Q-wave infarction obviously influences the release of troponin T into plasma, with all such cases showing peak values less than or equal to 26 h (median, 14 h) after the onset of symptoms. Troponin T concentrations in these patients returned to within the reference interval more rapidly than in nonreperfused subjects. In the 13 patients without fibrinolytic therapy, troponin T tended to peak approximately 48 h (median) after the onset of chest pain. Troponin T concentrations in patients for whom thrombolysis was unsuccessful resembled those in patients without fibrinolytic therapy. The specificity of the assay was 96% as tested in samples of 96 emergency-room patients. The reference interval (less than 0.5 micrograms/L) was established from samples of 100 healthy blood donors. Troponin T measurements are a specific and sensitive method for the early and late diagnosis of acute myocardial infarction and could, therefore, provide a new criterion in laboratory diagnosis of its occurrence.
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PMID:Cardiac troponin T in diagnosis of acute myocardial infarction. 159 99

In a substantial proportion of patients with suspected myocardial infarction, biochemical markers are needed for clinical decision-making at the time of admission, because electrocardiographic (ECG) recordings are inconclusive. We have assessed the usefulness for exclusion of myocardial infarction at admission of the newer markers creatine kinase MB (CK-MB) mass concentration, troponin T, and myoglobin in comparison with the routinely used markers creatine kinase (CK) and CK-MB activity. 290 consecutive patients were enrolled. Acute myocardial infarction was diagnosed on the basis of clinical history, ECG criteria, and time-dependent changes in CK and CK-MB activity. 153 patients had definite acute myocardial infarction. Troponin T had the highest sensitivity for prediction of acute myocardial infarction; high concentrations (above the upper reference limits) were found in 98 (64%) of the patients with infarctions compared with 92 (60%) for CK-MB mass concentration, 76 (50%) for myoglobin, 61 (40%) for CK activity, and 53 (35%) for CK-MB activity. However, troponin T also had the highest "false-positive" rate; of 137 patients without myocardial infarction, 36 (26%) had high troponin T concentrations. Sensitivity, specificity, and positive and negative predictive values were calculated in relation to time between onset of chest pain and hospital admission. Although CK-MB mass concentration was, by a small margin, the best marker in patients admitted within 8-10 h of onset of chest pain, all the markers had negative predictive values too low to allow exclusion of acute myocardial infarction at admission in patients with symptoms suggestive of myocardial infarction of less than 10 h duration.
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PMID:Failure of new biochemical markers to exclude acute myocardial infarction at admission. 790 80

The diagnostic performance of a new enzyme linked immunosorbent assay for the cardiac structural protein troponin T in the differential diagnosis of ischaemic cardiac damage was assessed. A well documented set of patients admitted to the coronary care unit of a district general hospital were studied. At a cutoff value of 0.2 micrograms/L, troponin T measurements 12-24 h after admission or 12-16 to 24-48 h from onset of chest pain showed an overall efficiency of 97.6% for diagnosis of proven myocardial infarction. Troponin T was not detectable in patients when ischaemic heart disease could be excluded but was present in four patients with angina. Detectable troponin T in these angina patients was associated with subsequent cardiac events.
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PMID:Troponin T for the differential diagnosis of ischaemic myocardial damage. 843 60

Elecsys assays for the cardiac markers Troponin T (cTnT) and CK-MB have been evaluated in an international multicenter study on the random access analyzer Elecsys 2010 to characterize their clinical performance and their comparability with respective established routine methods. In method comparison studies of Elecsys Troponin T (TnT) with Enzymun-Test TnT, good correlations (r > or = 0.95) and a high degree of correspondence (slopes in 4 laboratories between 0.95 and 1.05) were found. The method comparison studies of Elecsys CK-MB with various CK-MB routine methods lead to good correlations but some systematic deviation in the slopes due to varying standardization. In a reference population of 350 persons upper reference limits (97.5th percentile) of 0.03 milligrams/l for Elecsys TnT and 3.1 milligrams/l for Elecsys CK-MB were found. In cardiosensitivity studies the equivalent diagnostic information of the new Elecsys assays to routine methods was confirmed in the early diagnosis of acute myocardial infarction (AMI), the detection of minor myocardial damages in patients with unstable angina pectoris (UAP) and in time course data monitoring of AMI and bypass surgery patients. The superior sensitivity of cTnT versus CK-MB has been established in a screening situation where in 29 patients with cardiac diseases only cTnT, but not CK-MB, was found pathologically increased; this was due either to the larger diagnostic window of cTnT in AMI or to the more sensitive recognition of minor myocardial damage. In the same study, the cardiospecificity of Elecsys TnT was found to be at least 99.5%. This has also been demonstrated in an earlier study for Enzymun-Test TnT. Further cardiospecificity testing, e.g. in renal failure patients, showed results equivalent to those of Enzymun-Test TnT. An extended clinical study involving 294 patients with chest pain, of whom 58 had a final diagnosis of AMI, revealed highly comparable sensitivity and specificity for the Elecsys assays and routine methods. Thus, the already recommended clinical cut-off values of 0.1 milligrams/l for cTnT and 5 milligrams/l for CK-MB are also valid for the Elecsys assays. The slightly improved sensitivity of Elecsys TnT in the lower range even allows the recognition of pathological increase at cTnT concentrations below 0.1 milligrams/l in special situations with sufficient additional clinical information. Summarizing, provide the two cardiac markers on the Elecsys 2010 at least equivalent or even superior diagnostic information in various clinical situations of cardiac disease compared with routine methods. The short turn-around time and reliable performance qualify the Elecsys assays as new methods of choice for routine and emergency use.
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PMID:Clinical performance of the new cardiac markers troponin T and CK-MB on the Elecsys 2010. A multicentre evaluation. 967 71

The objective of our study was to validate the diagnostic utility of cardiac troponine T in acute ischemic syndromes, and also in cases of difficult diagnosis. We analyzed its concordance and compare them with conventional enzymatic quantitative methods. We determined sensitivity, specificity, positive and negative predictive values and likelihood ratio. Kappa index was used to know the concordance grade between T troponin and the positive or negative results of the quantitative enzymatic curve. Stochastic significance was valued by Chi square of Mcnemar test. In seventy patients who arrived to the hospital with chest pain who were assigned to five different groups. The sensitivity in quantitative markers was higher than qualitative methods, however the specificity, likelihood ratio was lower. In the total group the concordance analysis between qualitative and quantitative markers was adequate, (kappa index 0.65 p < 0.05). This study suggest that the rapid bedside qualitative test by cardiac Troponin T is a good diagnostic marker compared with conventional quantitative markers to evaluate chest pain in acute ischemic syndromes.
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PMID:[The utility of rapid qualitative determination of troponin T, the MB fraction of creatine phosphokinase and myoglobin in acute ischemic coronary syndromes]. 1036 23

Point-of-care (POC) or "near-patient" testing allows diagnostic assays to be performed in locations such as the emergency department or intensive care unit where treatment decisions are made and care is delivered based on the results of these assays. Presently, there exist POC immunoassays for several cardiac markers including creatine kinase MB (CK-MB), myoglobin, troponin I, and troponin T that yield qualitative and quantitative results comparable to traditional central lab assays. In the evaluation of emergency room patients with chest pain, POC cardiac markers may improve triage and clinical outcomes. Existing POC assays combining myoglobin and CK-MB have high sensitivity and specificity for diagnosing acute myocardial infarction and may provide the earliest identification of myocardial injury. POC Troponin T assays are the most studied POC cardiac marker assays. Along with POC troponin I assays, these tests provide more sensitive identification of myocardial injury and valuable prognostic information. Prior studies of POC cardiac marker assays have not addressed whether POC testing affects patient outcome or process of care. In situations in which caregivers base triage, treatment and monitoring decisions on time-sensitive diagnostic results, POC tests linked with improved triage and treatment strategies may improve resource utilization and clinical outcomes.
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PMID:Cardiac markers: point of care testing. 1045 Dec 48

Patients with chest pain represent an inhomogeneous group with greatly varying severity of coronary artery disease and cardiac risk. The proper selection of different treatment strategies in these patients requires reliable risk assessment. Patients with definitive myocardial infarction: in patients with ST-segment elevation on ECG, a positive troponin T (cTnT) on admission identifies a group of patients having a threefold higher mortality rate than patients with a negative cTnT test. The differences in risk based on cTnT are found for patients treated with thrombolytic as well as mechanical recanalization therapy. These differences in mortality based on admission cTnT may be explained by more severe coronary artery disease, worse left ventricular function, and less efficient microvascular reperfusion in the cTnT-positive patients. Patients with rest angina: in patients with angina at rest, a positive cTnT value on admission identifies a subgroup having a threefold higher cardiac event rate than cTnT-negative patients. The cTnT-positive patients seem to benefit from treatment with low molecular weight heparin and fibrinogen receptor antagonists, while cTnT-negative patients do not. The differences in risk and response to therapy may be due to more severe coronary artery disease, more critical coronary artery stenoses, and a higher rate of intracoronary thrombus formation in the cTnT-positive versus negative patients. Low risk chest pain patients: in low risk chest pain patients, (i.e. no rest angina, no ECG-changes) cTnT-positive patients on admission have a twofold higher cardiac event rate than cTnT-negative patients. The proper treatment strategy for the low risk cTnT-positive patients remains to be determined. Troponin T versus troponin 1: many of the findings on cTnT also relate to troponin I. However, there is a high interassay variability of troponin I assays, which has to be taken into consideration.
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PMID:Risk stratification and therapeutic decision making in patients with acute coronary syndrome--the role of cardiac troponin T. 1072 19

The use of troponin T to facilitate early patient discharge was investigated in a prospective study in a district general hospital. Troponin T was measured in 91 patients admitted over a period of 6 months with chest pain but without evidence of myocardial infarction. The main outcome measure was length of hospital stay. A negative troponin T was found in 70 patients. Fifty of these were discharged within 24 h of the troponin result being available and they had a significantly shorter hospital stay than a case control group and a historical control group from the previous 6 months. Troponin T measurement has a role in altering patient management by enabling early discharge, resulting in significant cost savings and increasing bed availability.
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PMID:Troponin T: role in altering patient management and enabling earlier discharge from a district general hospital. 1126 54

The authors performed a 6-month review of heart failure patients presenting to a teaching hospital emergency department to determine the rate of positive serum myocardial infarction markers. All patients with an emergency department discharge diagnosis of heart failure were included; those with a creatinine level >2.0 mg/dL were excluded. There were 151 patients who met the entry criteria, with a mean age of 68.6 +/- 13.6 years, and 84 (56%) were men. The mean ejection fraction was 32%, and the mean Framingham score was 3.8 +/- 1.6. Twenty (14%) had positive markers. Troponin T was positive in 17 (11%), and creatine kinase was positive in nine (6%). Both markers were positive in six (4%). Chest pain was absent in 70% of the positive marker group. The authors conclude that elevated cardiac markers are not rare in decompensated heart failure. These pilot data suggest these tests should be routinely obtained on heart failure patients.
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PMID:Retrospective review: the incidence of non-ST segment elevation MI in emergency department patients presenting with decompensated heart failure. 1468 2

The term "acute coronary syndrome" encompasses a range of thrombotic coronary artery diseases, including unstable angina and both ST-segment elevation and non-ST-segment elevation myocardial infarction. Diagnosis requires an electrocardiogram and a careful review for signs and symptoms of cardiac ischemia. In acute coronary syndrome, common electrocardiographic abnormalities include T-wave tenting or inversion, ST-segment elevation or depression (including J-point elevation in multiple leads), and pathologic Q waves. Risk stratification allows appropriate referral of patients to a chest pain center or emergency department, where cardiac enzyme levels can be assessed. Most high-risk patients should be hospitalized. Intermediate-risk patients should undergo a structured evaluation, often in a chest pain unit. Many low-risk patients can be discharged with appropriate follow-up. Troponin T or I generally is the most sensitive determinant of acute coronary syndrome, although the MB isoenzyme of creatine kinase also is used. Early markers of acute ischemia include myoglobin and creatine kinase-MB subforms (or isoforms), when available. In the future, advanced diagnostic modalities, such as myocardial perfusion imaging, may have a role in reducing unnecessary hospitalizations.
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PMID:Diagnosis of acute coronary syndrome. 1704 41


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