Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0151744 (myocardial ischemia)
 31,282 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Human albumin has the ability to bind cobalt at the N-terminus. The exposure of circulating albumin to ischemic tissue alters the ability of albumin to bind cobalt, probably through a mechanism involving free-radical production. The Albumin Cobalt Binding (ACB) test measures the alteration in albumin metal binding, and elevation of the ACB test is thought to be an early indicator of myocardial ischemia. In a previous multicenter study of chest pain patients presenting to the emergency department (ED), this test demonstrated high negative predictive value and sensitivity in the sample collected at presentation for predicting cardiac troponin I (cTnI)-negative or cTnI-positive results 6-24 h later. Since the completion of that report, the European Society of Cardiology (ESC) and the American College of Cardiology (ACC) have redefined the criteria for the diagnosis of acute myocardial infarction (AMI). The data from the multicenter ACB study were re-examined using the new diagnostic criteria for AMI to determine if combining the ACB test with troponin improved the sensitivity of either assay used alone for early diagnosis of AMI. Assay values were compared to either the final discharge diagnosis made at each site or to a diagnosis of AMI using the strict application of the ESC/ACC guidelines. Using the criterion of physician's discharge diagnosis and using blood collected at ED presentation, the cTnI test alone had a sensitivity of 23.9%, and the ACB test alone had a sensitivity of 39.1%, but the sensitivity significantly increased to 55.9% (p < 0.001 over cTnI alone) when both tests were used in combination. The sensitivity of the combination of ACB and cTnI tests at the 1- to 6-h time-point was 86.7% and at the >6- to 12-h time-point was 93.5%, but they were not significantly improved over the cTnI test alone. In conclusion, using the new ESC/ACC criteria, the combination also resulted in a statistically significant higher diagnostic sensitivity on blood collected at presentation. These data indicate a possible role of the ACB test in the early triage of patients with chest pain.
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PMID:Analysis of the Albumin Cobalt Binding (ACB) test as an adjunct to cardiac troponin I for the early detection of acute myocardial infarction. 1221 87

Recently a new biological marker, Ischemia Modified Albumin (IMA), measured by the Albumin Cobalt Binding (ACB) test, was introduced for detection of myocardial ischemia. During ischemia, the metal binding capacity of albumin for certain transition metals like cobalt is reduced. The precise mechanism of action for producing IMA is not known but appears to be related to the production of reactive oxygen species that modify the metal binding sites. The ACB test is a quantitative assay that detects IMA by measuring the cobalt binding capacity of albumin in human serum. We evaluated the analytical characteristics of the ACB test, and reagent and specimen stability, using the Cobas MIRA Plus instrument. Coefficients of variation for within-run and between-run assays were <4%. No significant interference was observed for concentrations of triglycerides and hemoglobin up to 7 mmol/l and 3.8 g/l, respectively. No interference was apparent with bilirubin. Measures from paired samples of heparinized plasma and serum were not equivalent. The assay is validated for commercial use with serum, therefore our study reported results for serum specimens only. All assays were completed within 5 hours after blood withdrawal. The one-sided upper 95th percentile, calculated for the ACB test in 150 healthy subjects, was 87.00 U/ml. There was no observed difference between men and women or with age. We conclude that the ACB test adapted on the Cobas MIRA Plus analyzer is satisfactory, but strict attention to sample handling procedures is necessary to maintain stability of the analyte.
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PMID:Analytical performance of the Albumin Cobalt Binding (ACB) test on the Cobas MIRA Plus analyzer. 1514 58

We studied the role of ischemia-modified albumin (IMA) with standard biomarkers (myoglobin, creatine kinase-MB [CK-MB], troponin I [TnI]) in assessment of 200 patients with suspected myocardial ischemia admitted to the emergency department. Every case was reviewed by a cardiologist. A clinical diagnosis of ischemia was assigned and correlated with biomarker test results. Of the patients, 25 (13.0%) had myocardial ischemia. Receiver operating characteristic curves demonstrated IMA as highly sensitive but somewhat poorly specific for the presence of ischemia (area under curve, 0.63; P = .01). With a cut point of 90 U/mL, the Albumin Cobalt Binding Test had 80% sensitivity and 31% specificity for diagnosing ischemia and a negative predictive value of 92%. IMA was positive in 4 of 5 patients with electrocardiographic (ECG) evidence of ischemia and 16 of 20 patients with coronary ischemia but negative ECG. Among the same patients, the myoglobin-CK-MB-TnI triad had a sensitivity of 57%. The combination of IMA-myoglobin-CK-MB-TnI increased the sensitivity for detecting ischemia to 97%, with a negative predictive value of 92%. IMA is highly sensitive and has a high negative predictive value, which might improve the usefulness of standard biomarkers of myocardial ischemia.
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PMID:Ischemia-modified albumin improves the usefulness of standard cardiac biomarkers for the diagnosis of myocardial ischemia in the emergency department setting. 1627 Apr 50

The biochemical marker of myocardial ischemia is detected prior to the development of myocardial necrosis, i.e. a novel biochemical evaluation based on human serum albumin binding to cobalt, a transitional metal. The evaluation is known as Albumin Cobalt Binding (ACB) Test. ACB Test is applied to detect the presence of Ischemia Modified Albumin (IMA), an albumin which has altered binding capacity to bind metal ion such as cobalt (Co), copper (Cu) and nickel (Ni) in N-terminus region. It is produced when the serum albumin convenes with ischemic heart tissues. ACB Test detecting the presence of myocardial ischemia that occurs prior to myocardial necrosis has been studied by some researchers and they found an ACB increase prior to troponin increase. The cut off point of ACB evaluation was 85 U/ml. Provided that the value was greater than 85 U/ml then there was positive myocardial ischemia. But it should be noticed that IMA increase in the plasma may be due to other tissues such as gastrointestinal tissues or skeletal muscles tissues. We should also consider other factors which may affect the evaluation result such as severe hypoalbuminemia that will cause a false-high result. ACB Test may be used as an early marker of myocardial ischemia that occurs prior to myocardial necrosis.
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PMID:Albumin cobalt binding (ACB) test: its role as a novel marker of acute coronary syndrome. 1679 11

Verification of the diagnosis of coronary artery disease (CAD) is based mostly on instrumental diagnostic techniques. Presently, there are no laboratory tests officially recommended for the diagnostics of myocardial ischemia (MI). Biochemical methods that would be able to verify MI in patients with suspected CAD have been under development since the 1990s. Ischemically modified albumin--IMA (Albumin Cobalt Binding test), glycogen phosphorylase BB, and free fatty acid-binding protein have been proposed as laboratory markers of MI. The article discusses advantages and disadvantages of IMA for diagnostics of MI in patients with acute coronary syndrome.
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PMID:[Albumin cobalt binding ability in assessment of myocardial ischemia in patients with acute coronary syndrome]. 1849 85