| Objective: unstable angina pectoris (UAP) refers to a lot of clinical anginal syndrome, between stable angina pectoris and acute myocardial infarction(AMI),which belongs to non ST -segment elevationacute coronary syndrome(NSTEACS). Because of the clinical unstability,this kind of patients have the risk to suffer from myoccadial infarction. So we must think highly of them. To make a fast and correct diagnosis and to deal with in a correct way is very important.In UAP patients,tropnin (TnI, TnT), myoglobin (MYO),creatine kinase isoenzyme (CK-MB),all of them are not elevatory, The variety of ST segment and T wave in electrocardiogram is a significant target to diagnose unstable angina pectoris. But clinically most chest pain patients'sympotoms have already gone when they are in doctor's office visiting.At this time ,there is about half patients'ECG is normal, or there is no specific change.Ischemia -modified albumin(IMA) is a sensitive biochemical marker in the early myocardia lischemia. Studies have proved IMA immediately to heighten in a few minutes and reach the peak time during 2 to 4 hours when myocardial ischemia happened, and IMA to go back baseline when ischemia stopping in about 6 hours. This study aims to investigate the early diagnostic value of Ischemia-modified albumin(IMA)in unstable angina pectoris patients, and to analyze the early diagnostic value of Ischemia-modified albumin in unstable angina pectoris patients when their ECG is normal or is no specific change.Methods: Enrolled 72 patients with unstable angina pectoris,who were in hospitalization,and whose onset were break out once again in hospital.Chest pain persistence time less than 20 minutes,and myocardial marker(cTnI) is normal.If chest pain larger than 20 minutes,according to myocardial marker after 4-6 hours and CAG,he should be rejected if he is diagnosed acute myocardial infarction. If the chest pain occurred in 6 hours for the second or the third time,it should be recompute the time according to the last time(0case). According to electrocardiogram(ECG) change or not in ten minutes of chest pain onset ,which contrast with routine ECG, divide into ECG changed group (39cases) and unchanged group (33cases). All patients'blood sample were collected to test IMA in 30 minutes,2hour,4hour,6hour.To analyse the change of IMA by the time change and the two group have difference or not.The healthy group (32 cases) were healthy of physical examination centre.Results: 1. Unstable angina pectoris group own control and compare with healthy control group(1)The IMA value of UAP at 30min,2h,4h,6h and of healthy control group each is 58.358±5.405, 68.463±4.301, 67.206±4.084, 55.486±5.174, 45.444±3.541. 95% confidence interval is (57.088,59.628), (67.452,69.473),(66.246,68.165),(54.279,56.702),(44.170,46.721). (2)According to analysis of variance to understand: there is statistical significance among the IMA value each time point of unstable pectoris angina group and of healthy control group(F=197.62,P=0.000). they pairwise comparisons by SNK method known: every pairwise have difference ,and the diffence have statistical significance,all value of P less than 0.05.(3) According to the first statistical chart know: In UAP group ,IMA begins to rise after 30 min of the onset,and reach a high peak at 2h,later,to begin fall-off and descent obviously at 6h ,but also high ,and have statistis significance compare to the healthy group.(4) According to the second statistical chart known: Area Under ROC Curve is 0.984,95% similar reference confidence intervals is(0.966,1.001 ),cutoff value is 48.95. when IMA larger than 48.95 is positive, The sensitivity of IMA to diagnose UAP is 97.2%,and specificity is 87.5%,positive predictive value is94.6% and negative predictive value is 93.3%. This demonstration :IMA is a more ideal biomarker to diagnose UAP.(5) Adopt multiple stepwise regression to analyze:IMA whether or not have been affected by age, sex, lipoprotein (TCH, TG, LDL, HDL), hypertension,diabetes mellitus, total protein albumin,blood sugar's level when fall ill and so on. To select variables ingress value isа=0.10, to reject value isа=0.15.There are non variables to be selected when IMA at30min,2h,6h point. when IMA at 4 hour point,only ALB enter equation,regression coefficient is 0.258,multiple correlation coefficient is 0.229,coefficient of determination is 0.053. The analytic result of variance is F=3.888,P=0.053, this means equation of multiple linear regression is not statistically significant. This mean IMA at 4 hour point relevant to ALB only, but effect little. Sum up: In this design proposal,age,sex,lipoprotein(TCH,TG,LDL,HDL),hypertension, diabetes mellitus, total protein,albumin, blood sugar's level when fall ill and so on which can not affect on IMA.2. Compare the ECG changed group with unchanged group of unstable angina pectoris.(1)The IMA value of the ECG unchanged group at 30min,2h,4h,6h each is 58.690±5.495 69.170±4.450 68.030±4.222 56.060±5.840; The IMA value of the ECG changed group at 30min,2h,4h,6h each is :58.070±5.382 67.870±4.134 66.508±3.881 55.000±4.556. (2)According to the analysis of variance of repeated measurement known: there are not statistical significance between the ECG changed group and unchanged group(F =1.318,P=0.255), and have statistical significance at the different time point of the group inner(F=401.979,P=0.000),and there is no interaction between the time and the group (F=0.361,P=0.734). At different determine time point ,every pairwise comparisons have difference ,and the difference have statistical significance,all value of P less than 0.001.(3). According to the third statistical chart known:The tendency of variation was the same between the ECG changed group and unchanged group.Both the ECG changed group and the unchanged group are IMA begain to rise after 30min of the onset,and reach a high peak at 2-4h,and descent obviously at 6h, At the same time point , compare the ECG changed group with the ECG unchanged group , P of all>0.05, 30min, P=0.6310,2h, P=0.4917,4h, P=0.1158,6 h ,P=0.3901.Conclusion:1. IMA can be an earlier biomarker for the unstable pectoris angina patients.2. At the early stage of chest pain of the unstable pectoris angina patients, there is no relation between the rise of IMA and whether the change of ECG or not. That is to say, The early diagnostic value is even bigger for the unstable pectoris angina patients when the ECG is normal or unspecificity . |
