Diagnosis of ischemic heart disease using CK-MB, troponin-I and ischemia modified albumin.

BACKGROUND

Diagnosis of cardiac ischemia in patients attending emergency department with symptoms of acute coronary syndrome (ACS) is often difficult. Biochemical tests like cardiac troponin (cTnI/T) and CK-MB may not rise during reversible myocardial ischemia. Previous reports suggest that oxidative damage due to ischemic conditions rapidly modifies human serum albumin and reduce its capacity to bind exogenous cobalt. Ischemia modified albumin (IMA) has shown to be a sensitive and early biochemical marker.

OBJECTIVE

To validate the use of IMA albumin as a diagnostic test for ischemic heart disease and compare its efficacy with CK-MB and cTnI.

METHODS

Four sequential samples from 25 patients admitted to MICU, TASH were tested for IMA. Thirty addiional samples from healthy volunteers were assayed to establish the reference range of IMA. Patients were classified as AMI and non-AMI groups based on the clinical presentation, ECG and echocardiography findings. Colorimetrically assayed parameters included: total protein, albumin, urea, creatinine, CKT and IMA.

RESULTS

High number of male patients with old age were diagnosed as having AMI. Mean IMA levels were increased in patients with ACS compared to the control group and patients with Non-AMI. The mean +/- SEM value of IMA for the patient group was 83.0 +/- 6.6, which is significantly higher (p = 0.0001) than the control group with mean IMA 26.0 +/- 1.2. IMA has demonstrated a sensitivity and specificity of 100% and 85.3% respectively, and an area under the receiver operator characteristics (ROC) curve as 0.948 (95% confidence interval (CI): 0.914-0.983. The overall efficacy of IMA in differentiating AMI from Non-AMI cases appears to be comparable to that of CK-MB and cTnI.

CONCLUSIONS

The IMA Test can be assayed by simple and quick method, which may serve as a useful diagnostic tool for the assessment of myocardial ischemia/infarct.