[Combined myocardial injury markers for diagnosis of acute myocardial infarction].
OBJECTIVE
To compare the diagnostic accuracy of different myocardial injury markers and their combinations in diagnosing acute myocardial infarction (AMI).


METHODS
The myocardial injury markers: AST, CK, CK-MB, LDH, HBDH, cTnI, CK-MB mass were detected in patients with acute chest pain-onset who were hospitalized in Sichuan University West China Hospital from July 2005 to October 2006. The accuracy of those markers in diagnosing AMI were evaluated by their sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, and negative likelihood ratio. Student t-test and one-way ANOVA were performed to compare the diagnostic accuracy of the markers.


RESULTS
cTnI had the highest diagnostic accuracy, with 85% of sensitivity and 92.5% of specificity (P < 0.05). cTnI in parallel with myocardial enzymes produced the highest combined diagnostic accuracy, with 100% of sensitivity and 37.29% of specificity (P < 0.05). Myocardial enzymes in sequence with cTnI produced the highest sequential diagnostic accuracy, with 50% of sensitivity and 100% of specificity (P < 0.05).


CONCLUSIONS
cTnI is the best indicator for diagnosis and differential diagnosis of AMI. Myocardiozymogram is poor in sensitivity and specificity, which should be used only in combination with cTnI or CK-MB mass. Parallel testing can increase sensitivity, while sequential testing can improve specificity.
Jia
Cheng-Yao
CY
Department of Cardiology, West China Hospital, Sichuan University, Chengdu 610041, China.
Wang
Li
L
Mao
Zhi-Gang
ZG
Zhang
Ju-Long
JL
Zhang
Li
L
D015415:Biomarkers / Q000097:blood*; D052279:Creatine Kinase, MB Form / Q000097:blood*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood / Q000175:diagnosis*; D012680:Sensitivity and Specificity; D019210:Troponin I / Q000097:blood*
D015415:Biomarkers; D019210:Troponin I; D052279:Creatine Kinase, MB Form