| Objective: Because of its unique biological characteristics, cardiac troponin I turns into the high sensitivity and high specificity target after myocardial cell injury. It has the higher value in the diagnosis of non-ST-segment elevation acute coronary syndrome (NSTE-ACS), evaluation of the degree of myocardial injury, condition monitoring and prognostic evaluation. There are some researches which have proved that ST-segment elevation in lead aVR has great significance in the patients of NSTE-ACS. The aim is to investigate the predictive value of positive troponin I and ST-segment elevation in lead aVR on early prognosis in the patients with NSTE-ACS, and to evaluate troponin I and ST-segment elevation in lead aVR as the predictor of the risk for the combined end points of cardiac events.Material and methods:The study selected 265 cases of NSTE-ACS from 2008 to 2009 in Cangzhou Central Hospital. All patients were diagnosed as NSTE-ACS corresponding by 2004 criterion of Chinese Medical Association. In 265 cases, 10 cases are missed to follow, and the remaining 255 cases are selected (175 males and 80 females, mean age 67±10). Selection criterion:⑴unstable angina, including:①Initial angina②accelerated effort angina③rest angina④postinfarction angina;⑵non-ST-elevation myocardial infarction. Exclusion criteria:⑴variant angina,⑵PCI in resent time(<6 months),⑶bundle branch block or intraventricular block,⑷severe liver disease, kidney disease or cerebral vascular disease,⑸hematologic diseases.The patients were tested blood in common, including cardiac troponin I (cTn I), high-sensitivity c-reactive protein, myocardial enzymes (outcome measure is CK-MB). Reference value: cTn I 0~0.4 ng/ml, hs-CRP 0~25u/L, CK-MB 0~25u/L. The indicator which is higher than the reference is positive.The U.S. GE MAC-5000 Synchronous 12-lead ECG was used to record the patients'standard 12-lead ECG when they admitted to hospital immediately (paper speed 25 mm /s, voltage 10 mm /mV). The basic point of ST segment was the starting point of QRS complex. The basic line was the previous TP-segment. The measuring point which was 80ms after J point is used to test. Six ST-segments were continued to measure, and the average of them was as the measured data. It was significance that the range≥0.5mm of any ST-segment deviated from the baseline. Record the lead offset value, especially the aVR ST-segment elevation.The patients after admitted to hospital immediately took aspirin 300mg, clopidogrel 300mg. Thereafter, they daily took aspirin 200mg, clopidogrel 75mg, low molecular weight heparin subcutaneous, and took expanding coronary drug or controlling heart rate drug according to the condition. In a stable condition after one week, they were taken coronary angiography (CAG) by transradial access. The outcome of CAG was interpreted by two professional and technical personals that didn't know the study, and then choose therapeutic scheme on the basis of the outcome of CAG: percutaneous coronary intervention (PCI), coronary artery bypass grafting (CABG) or drug conservative therapy. After the operation, all of them were given the drugs including anticoagulant drugs, antiplatelet aggregation drug, and etc. Observe the cases that occurred complication in perioperative period, nonfatal myocardial (re)infarction and cardiovascular mortality. All patients were followed up for 6 months by telephone interviews and out-patient review, and were observed whether they had the following occurrence of the primary end piont: nonfatal myocardial infarction (including re-infarction), cardiovascular mortality and target vascular revascularization (including re-PCI and CABG).Statistical analysis: Continuous data was expressed as means±SD, and categorical data was expressed as percentages. Continuous data was used t-test. Categorical data was used chi-square test. Independent risk factor was used logistic regression analysis. SPSS13.0 statistic software was used to analysis all the data, and statistical significance was indicated by p value<0.05.Results: In the following-up of 6 months, increased cTn I (OR=7.01, 95% CI=1.22~12.63, p=0.02) and ST-segment elevation in lead aVR (OR=1.38, 95% CI=1.084~1.751, p=0.009) were the only independent predictors of death and myocardial (re)infarction. And increased cTn I (OR=1.249, 95% CI=1.114~1.501, p<0.01) and ST-segment elevation in lead aVR (OR=4.46, 95% CI=0.81~5.22, p<0.01) were the only independent predictors of the adverse cardiovascular events, including myocardial infarction, myocardial re-infarction, cardiovascular death and reline revascularization. With increased cTn I and ST-segment elevation in lead aVR on admission, the patients of non-ST-segment elevation acute coronary syndrome had the most cases of left main or 3-vessel coronary disease, and had the most cases of 6-month adverse outcomes.Conclusion: The study showed that in the following-up of 6 months, increased cTn I and ST-segment elevation in lead aVR were both the important factors to predict poor prognosis of the patients with NSTE-ACS. Through multi-factor correlation analysis, increased cTn I and ST-segment elevation in lead aVR were the only independent predictors of death, myocardial (re)infarction, myocardial re-infarction and reline revascularization. The other variables examined, including gender, age, previous myocardial infarction, previous revascularization, ST-segment depression in leads other than aVR on admission, high-sensitive c-reactive protein, and CK-MB were not significant predictors. And combination of two factors more than any one of them can better predict the prognosis of patients with NSTE-ACS. Patients with increased cTn I and ST-segment elevation in lead aVR had the highest rates of left main or 3-vessel coronary disease and of major adverse events at 6 months. In patients without increased cTn I, the rate of left main or 3-vessel coronary disease was low, but ST-segment elevation in lead aVR was associated with increased adverse events. cTn I and ST-segment status in lead aVR on admission can be simply and easily evaluated, making them useful tools for risk stratification in NSTE-ACS, judging prognosis, treating early and accurately.
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