Utility of admission cardiac troponin and "Ischemia Modified Albumin" measurements for rapid evaluation and rule out of suspected acute myocardial infarction in the emergency department

Abstract

Objective: To assess if the combination of cardiac troponin (cTn) and Ischemia Modified Albumin (IMA) can be used for early exclusion of acute myocardial infarction (AMI). Methods: Prospective consecutive admissions to the emergency department (ED) with undifferentiated chest pain were assessed clinically and by electrocardiography. A total of 539 patients (335 men, 204 women; median age 51.9 years) considered at low risk of AMI had blood drawn on admission. If the first sample was less than 12 hours from onset of chest pain, a second sample was drawn two hours later, at least six hours from onset of chest pain. Creatine kinase MB isoenzyme (CKMB) mass was measured on the first sample and CKMB mass and cTnT on the second sample. An aliquot from the first available sample was frozen and subsequently analysed for IMA. If cTnT had not been measured on the original sample cTnI was measured (n = 189). Results: Complete data were available for 538/539 patients. IMA or cTn was elevated in the admission sample of all patients with a final diagnosis of AMI (n = 37) with IMA alone elevated in 2/37, cTn alone in 19/37, and both in 16/37. In 173/501 patients in whom AMI was excluded both tests were negative. In the non-AMI group 22 patients had elevation of both IMA and cTn in the initial sample, suggesting ischaemic disease. Conclusion: Admission measurement of cardiac troponin plus IMA can be used for early classification of patients presenting to the ED to assist in patient triage.

Clinical Assessment of Ischemia‐modified Albumin and Heart Fatty Acid–binding Protein in the Early Diagnosis of Non‐ST‐elevation Acute Coronary Syndrome in the Emergency Department

“…According to other studies, the specificity of IMA for ACS detection is limited. 25,30,33 In our study, the ROC curve did not show a cutoff value to discriminate patients according to the presence of ACS. The curve points lay fairly close to the diagonal line with numerous true and false positives.…”

“…36 Contrary to previous studies, we studied patients with episodes of chest pain (persistent or not) suggesting a diagnosis of ACS to the EP, evolving within 12 hours. 25,30,33 In a study by Collinson et al, 33 patients with significant ECG changes, comorbidity requiring hospital admission, suspected or proven alternative source of chest pain requiring hospital admission, known CAD with unstable angina, and atypical clearly noncardiac chest pain were not included. 33 Thus, their patients were highly selected with a bias toward a high likelihood of an ACS diagnosis.…”

“…25,30,33 In a study by Collinson et al, 33 patients with significant ECG changes, comorbidity requiring hospital admission, suspected or proven alternative source of chest pain requiring hospital admission, known CAD with unstable angina, and atypical clearly noncardiac chest pain were not included. 33 Thus, their patients were highly selected with a bias toward a high likelihood of an ACS diagnosis. Because the prevalence of ACS in our study was lower, the predictive values were not overestimated, and the results can be extrapolated to the general population.…”

“…In those studies, the patients were not ''all comers,'' and the prevalence of ACS was unusually high in contrast to the real-life situation in a big city ED. 25,30,[33][34][35] We included in our study patients who were more representative of the population admitted to the ED with chest pain. 36 Contrary to previous studies, we studied patients with episodes of chest pain (persistent or not) suggesting a diagnosis of ACS to the EP, evolving within 12 hours.…”

Ischemic Modified Albumin (IMA) as a Novel Marker for Ischemic Heart Disease and Surrogate Marker for Other High Oxidative -Ischemic Conditions

“…3 Cardiac ischemia is the most common mechanisms underlying acute coronary syndrome (ACS). 4,5 Ischemia modified albumin (IMA) is produced as a result of tissue ischemia and is present in blood in easily detectable concentrations. 6,7 We thus decided to find out the utility of ischemia modified albumin (IMA) in patients suspected of acute coronary syndrome, its role to predict adverse outcome with high IMA and thus short and long-term prognostic significance of high ischemia modified albumin (IMA) during hospitalizations and for six months after discharge as this has not been studied previously.…”