Diagnostic value of ischemia-modified albumin in patients with suspected acute coronary syndrome.
BACKGROUND
Ischemia-modified albumin (IMA) has been proposed as a useful rule-out marker for the diagnosis of acute coronary syndrome (ACS) in the emergency department. This study evaluated the ability of IMA to predict the acute myocardial infarction (AMI) diagnosis in a population of chest pain patients.


METHODS
The study population comprised 107 subjects (men, 62%; women, 38%) admitted with suspected ACS. None of the patients had ST-segment elevations that qualified for immediate revascularization. Ischemia-modified albumin was determined from serum with albumin cobalt binding test (Inverness Medical Innovations Inc, Stirling, UK). Furthermore, cardiac troponin T, creatinine kinase MB mass, myoglobin, and heart-type fatty acid binding protein (H-FABP) were determined on arrival, after 6 to 9 hours, and after 12 to 24 hours. All patients had at least 2 blood samples taken to exclude/verify the AMI. AMI was defined by a cardiac troponin T level greater than 0.03 microg/L.


RESULTS
Thirty-three percent of the patients (n = 35) had a final diagnosis of AMI. The sensitivity of admission IMA for a final diagnosis of ACS was 0.86 (95% confidence interval [95% CI], 0.69-0.95). Specificity was 0.49 (95% CI, 0.36-0.60). Negative predictive value was 0.88 (95% CI, 0.72-0.95). The optimal cutoff threshold derived from the receiver operating characteristics (ROC) curve (ROC analysis) was determined as 91 U/mL. The area under the ROC curve was 0.73. Ischemia-modified albumin did not, at any time, provide superior sensitivity or specificity compared with other biomarkers. We do not find the data supportive of IMA as a standard marker in the emergency department.
Department of Cardiology, Cardiovascular Research Centre, Aalborg Hospital, Aarhus University Hospital, DK-9000 Alborg, Denmark. sph@dadlnet.dk
Søren
S
Hjortshøj
Søren Risom
SR
Kristensen
Jan
J
Ravkilde
D054058:Acute Coronary Syndrome / Q000175:diagnosis; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D002637:Chest Pain / Q000209:etiology*; D003718:Denmark; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis; D017202:Myocardial Ischemia / Q000097:blood* / Q000175:diagnosis*; D011237:Predictive Value of Tests; D012372:ROC Curve; D011933:Reagent Kits, Diagnostic; D012709:Serum Albumin / Q000032:analysis*
D015415:Biomarkers; D011933:Reagent Kits, Diagnostic; D012709:Serum Albumin