Ischemia Modified Albumin Combined With Two-dimensional Speckle Tracking Imaging In The Early Diagnosis Of Unstable Angina

Research background:For a long time,diagnosis of unstable angina(UA)based on clinical symptoms of chest pain and ST-T change in electrocardiogram(ECG)at the onset of chest pain,but most of the patients can not be timely examined ECG when they have chest pain,while ECG has been restored to normal or changes do not have diagnostic significance coming to the hospital.Therefore,early diagnosis of UA has become an urgent problem to be solved.In recent years,it has been found that ischemia modified albumin(IMA)is a sensitive index for early identification of myocardial ischemia,but its specificity is poor;while the two-dimensional speckle tracking imaging(2D-STI)has a high specificity for quantitative recognition of myocardial ischemia,but its sensitivity is poor.Objective:Using the receiver operating characteristic curve(ROC curve),explore the clinical significance of combined application of ischemia modified albumin(IMA)and the index of two-dimensional speckle tracking imaging(2D-STI)----left ventricular global peak longitudinal strain(GPLS)in the early diagnosis of unstable angina(UA).Methods:According to the results of coronary angiography,123 patients who had single lesion of left anterior descending coronary artery,stenosis greater than 70% and treated with PCI were selected as the experimental group;78 patients who had not coronaryartery stenosis as the control group.Two groups were recorded during the operation of chest pain symptoms and the standard 12 lead ECG,and detected IMA and echocardiography in the preoperative and postoperative respectively.Using 2D-STI determine the peak systolic longitudinal strain of 17 left ventricular segments,then calculate the global peak longitudinal strain(GPLS).Determine the Cut-off of IMA and GPLS for the diagnosis by using ROC curve.Using two combined diagnosis method,parallel diagnostic test and serial diagnostic test,evaluate diagnostic value of IMA combined with GPLS(2D-STI)to early diagnosis UA.Results:1.The preoperative IMA was 43.56 + 9.38(U/ml)in the PCI group and 44.55 +8.81(U/ml)in the control group,and there was no statistically significant difference between the two groups(P > 0.001);the postoperative IMA was 82.80 + 14.28(U/ml)in the PCI group and 59.91 + 18.29(U/ml)in the control group,and there was no statistically significant difference between the two groups(P > 0.001).2.The preoperative GPLS was-21.29±1.23(%)in the PCI group and-21.47±1.53(%)in the control group,and there was no statistically significant difference between the two groups(P > 0.001);the postoperative GPLS was-18.20±2.74(%)in the PCI group and-21.28±2.39(%)in the control group,and there was no statistically significant difference between the two groups(P > 0.001).3.The area under of IMA of ROC curve of was 0.799[95%CI:0.734,0.864,P <0.001],and the area under of GPLS of ROC curve of was 0.790[95%CI:0.726,0.853,P <0.001];The area under of IMA combined with GPLS of ROC curve of was0.900[95%CI:0.859,0.940,P < 0.001].4.The sensitivity and specificity of IMA in the early diagnosis of UA were 83.3%and 70.7%,and mistake diagnostic rate and omission diagnostic rate were 29.3% and16.7%;The sensitivity and specificity of GPLS in the early diagnosis of UA were 72.5%and 82.9%,and mistake diagnostic rate and omission diagnostic rate were 17.1% and27.5%.5.In parallel diagnostic test,the sensitivity and specificity of IMA combined with GPLS in the early diagnosis of UA were 93.3% and 53.7%,and mistake diagnostic rate and omission diagnostic rate were 46.3% and 6.7%.6.In serial diagnostic test,the sensitivity and specificity of IMA combined with GPLS in the early diagnosis of UA were 59.2% and 100%,and mistake diagnostic rate and omission diagnostic rate were 0% and 40.8%.Conclusion:1.The diagnosis accuracy IMA combined with GPLS(2D-STI)in the early diagnosis of UA is higher than IMA,GPLS(2D-STI)respectively in the early diagnosis of UA.2.IMA combined with GPLS(2D-STI)by using the parallel diagnostic test can improve the sensitivity in early diagnosis of UA,and reduce the omission diagnostic rate;IMA combined with GPLS(2D-STI)by using the serial diagnostic test can improve the specificity in early diagnosis of UA,and reduce the mistake diagnostic rate.3.The purpose in the early diagnosis of UA in clinically is to reduce the omission diagnostic rate,we can use the parallel diagnostic test of IMA combined with 2D-STI to early diagnose UA.