Comparison of the diagnostic accuracy of ischemia-modified albumin and echocardiography in patients with acute chest pain.
BACKGROUND
Several imaging tests and biomarkers have been proposed for the identification of patients with unstable angina among those presenting to the emergency department with acute chest pain. Preliminary data suggest that ischemia-modified albumin (IMA) may represent a potentially useful biomarker in these patients.


OBJECTIVE
To compare IMA and echocardiography in excluding unstable angina in patients with acute chest pain.


METHODS
Thirty-three patients (mean [± SD] age 59.8±10.8 years; 28 men) presenting to the emergency department with acute chest pain lasting <3 h suggestive of acute coronary syndrome, with normal or non-diagnostic electrocardiograms, and creatine kinase MB and troponin levels within the normal range, were included in the present study.


RESULTS
After further diagnostic evaluation, five patients (15.2%) were diagnosed with unstable angina. The sensitivity, specificity, positive predictive value and negative predictive (NPV) value of echocardiography for diagnosing unstable angina was 60.0%, 89.3%, 50.0% and 92.6%, respectively. The area under the ROC curve for diagnosing unstable angina based on the serum IMA levels was 0.193 (95% CI 0.047 to 0.339; P<0.05). Based on ROC curve analysis, serum IMA levels ≥31.95 IU/mL yielded the optimal combination of sensitivity and specificity for diagnosing unstable angina. The sensitivity, specificity, positive predictive value and NPV of serum IMA levels ≥31.95 IU/mL for diagnosing unstable angina was 40.0%, 28.6%, 9.1% and 72.7%, respectively.


CONCLUSIONS
Measurement of serum IMA levels appears to represent a useful tool for excluding unstable angina in patients presenting to the emergency department with acute chest pain. Moreover, IMA shows an NPV that is comparable with echocardiography.
Second Propedeutic Department of Internal Medicine, Medical School, Aristotle University of Thessaloniki, Hippokration Hospital, Thessaloniki, Greece.
Evangelia
E
Kountana
Konstantinos
K
Tziomalos
Panagiotis
P
Semertzidis
Fani
F
Dogrammatzi
Aristidis
A
Slavakis
Stella
S
Douma
Chrysanthos
C
Zamboulis
Paraschos
P
Geleris
Acute chest pain; Acute coronary syndromes; Echocardiography; Ischemia-modified albumin; Unstable angina