Myocardial infarction false alarm: initial electrocardiogram and cardiac enzymes.
OBJECTIVE
The objectives of this study were to determine the incidence of a myocardial infarction "false alarm" and evaluate the efficacy of the initial electrocardiogram and cardiac enzymes in diagnosing myocardial infarction in Malaysia.


METHODS
We recruited patients who were admitted with suspected myocardial infarction from June to August 2008. The medical records of these patients were reviewed for the initial electrocardiogram, initial cardiac enzyme levels (creatinine kinase-MB and troponin T), and the final diagnosis upon discharge. The subjects were stratified into 2 groups: true myocardial infarction, and false alarm.


RESULTS
125 patients were enrolled in this study. Following admission and further evaluation, the diagnosis was revised from myocardial infarction to other medical conditions in 48 (38.4%) patients. The sensitivity and specificity of the initial ischemic electrocardiographic changes were 54.5% and 70.8%, respectively. Raised cardiac enzymes had a sensitivity of 44.3% and specificity of 95.8%.


CONCLUSIONS
A significant proportion of patients in Malaysia are admitted with a false-alarm myocardial infarction. The efficacy of the electrocardiogram in diagnosing myocardial infarction in Malaysia was comparable to the findings of Western studies, but the cardiac enzymes had a much lower sensitivity.
Department of Medicine, International Medical University, Seremban, Malaysia.
Esha Das
ED
Gupta
Rajalingham
R
Sakthiswary
D000328:Adult; D000368:Aged; D015415:Biomarkers; D004796:Clinical Enzyme Tests; D052279:Creatine Kinase, MB Form / Q000097:blood*; D003937:Diagnosis, Differential; D003951:Diagnostic Errors / Q000517:prevention & control; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008296:Malaysia; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood / Q000175:diagnosis* / Q000503:physiopathology; D010343:Patient Admission; D010351:Patient Discharge; D011237:Predictive Value of Tests; D020107:Troponin T / Q000097:blood*; D015854:Up-Regulation
D015415:Biomarkers; D020107:Troponin T; D052279:Creatine Kinase, MB Form
Biological markers; MB form; creatine kinase; electrocardiography; malaysia; myocardial infarction; troponin T