The value of combined detection of myocardial injury markers in the early diagnosis of acute myocardial infarction

Abstract

Objective To explore the clinical value of combined detection of serum ischemia modified protein (IMA), myoglobin (Mb) and troponin I (cTnI) levels in the early diagnosis of acute myocardial infarction (AMI). Methods The research group selected 115 cases patients who were diagnosed as AMI in emergency and cardiology departments of the People′s Hospital of Gaotang County from January 2015 to December 2017. Fifty cases of healthy subjects were selected as control group. Serum IMA, Mb and cTnI levels at the time of 0.5 h, 6 h and 12 h after admission in the research group and those in the normal control group were measured, and the statistical analysis was conducted to compare the sensitivity, specificity and diagnostic coincidence rate of serum IMA, Mb and cTnI in the early diagnosis of AMI. Through the area under the receiver operating characteristic (ROC) curve (AUC) to compare the value of each index in the early diagnosis of AMI. Results 0.5 h, 6 h, 12 h after admission, comparing the serum IMA levels [(128.35±13.53)U/ml, (104.27±11.64)U/ml, (84.73±6.97)U/ml], Mb levels [(161.83±15.64)μg/L, (311.44±40.92)μg/L, (470.45±46.81)μg/L], cTnI levels [(0.31±0.05)μg/L, (12.56±2.73)μg/L, (74.84±6.37)μg/L] of research group, to the control group [(32.34±3.57)U/ml, (51.47±8.53)μg/L, (0.27±0.03)μg/L], the differences were statistically significant (F=65.42, 52.21, 67.46, all P<0.01). At the time of 12 h after admission, the sensitivity of IMA, Mb and cTnI were 80.58%, 86.65% and 59.63% respectively, the specificity were 45.14%, 34.57% and 88.32% respectively, the diagnostic coincidence rates were 72.81%, 75.48%, 89.56% respectively. The sensitivity, specificity and diagnostic coincidence rates of IMA+ Mb+ cTnI combined detection were 74.34%, 91.56% and 92.69% respectively. The AUC of IMA, Mb, cTnI single detection and IMA+ Mb+ cTnI combined detection for AMI diagnosis were 0.618, 0.582, 0.822, and 0.914, respectively. The AUC of IMA+ Mb+ cTnI was the largest, which had high diagnostic efficiency and was superior to the single detection of IMA, Mb and cTnI. Conclusion The combined detection of serum IMA, Mb and cTnI can provide a better reference for the early diagnosis of AMI, and has important clinical value for the early exclusion and diagnosis of AMI. Key words: Myocardial infarction; Troponin I; Myoglobin; Early diagnosis