The Relationship Of RDW On The Long-term Survival Rate Of Patients Who Suffered NSTE-ACS And Got A Percutaneous DES Implantation

BackgroundAcute Coronary Syndrome(ACS) is a general term that describe acute myocardial ischemic diseases caused by coronary artery diseases charaterized by high morbidity and high death rate. It includes ST-elevation acute myocardial infarction(STE-AMI) and Non ST-elevation acute coronary syndrome(NSTE-ACS). Besides, the latter can be divided into unstable angina(UA)and Non ST-elevation acute myocardial infarction (NSTE-AMI). It have been confirmed that the rapture of vulnerable plaques have an intimate relation with the pathogenesis of NSTE-AMI. The superficial fibrous cap of these plaques are very thin but they are rich in cholesterol, being named as atheromatous plaques at the same time. Under the stimulation of non-bacterial imflammatory substance, the arterial wall will get an imflammation. What’s more, with the stimulation of other factors, such as hypertension, stress or the going up of catecholamine level, the plaques will crack or ulcerate so that the collagen under the endothelium get exposed and this activates the platelet, raising macrophagocytes as well as smooth muscle cells to release related tissue factors into blood which activates blood coagulation. There are various kinds of clinical symptoms of NSTE-ACS patients and the actual situation is far more complex. Some patients have mild symptoms and the prognosis inclines to as good as stable angina while others stands quite the opposite with worse prognosis and some may develop myocardial infarction or pass away in a really short time. Thus, to give a risk stratification of NSTE-ACS during clinical practice is of great importance. The commonest marking system is the TIMI risk marking model, which includes the following 7 indicators;1.Age over 65 years old;2. At least three risk factors of Coronary Heart Disease(CHD);3. The coronary artery narrows down more than 50%;4. ST changes on ECG;5.Angina attacks at least twice within 24hs;6.Usage of Asprin within 7 days;7. Growing up of cardiac markers.Each indicator accounts for one point and we’ll get the TIMI risk points after having all of it adding together.0 to 2 points is affiliated to the low-risk group,3 to 4 points for the middle-risk group, and 5 to 7 points are those with high risks. Different patients are supposed to give a risk stratification as soon as possible so as to take different dealing methods as early as it can be. The percutaneous coronary drug-eluting stents (DES) implantation is a current effective method benefiting most NSTE-ACS patients even though there are still a small number of patients ending with bad prognosis.RDW is an index that reflects the size of red blood cells and it is mainly used to diagnose and classify anemia. With further study into it, some scholars find that RDW have a tight corelation to cardiovascular diseases, heart failure and stroke. Some figure out that the elevating of RDW has something to do with the poor prognosis of STE-ACS patients. However, research about the relation of RDW and the long-term survival rate of Patients who suffered NSTE-ACS and got a percutaneous DES implantation is rare and deficient. Therefore, this study aims to explore the prognostic value of RDW for NSTE-ACS patients with DES implantation.Purpose of research:To evaluate the influence of RDW on the long term prognosis of NSTE-ACS patients with percutaneous DES implantation.Material and Method1.Clinical dataOur research team selected 181 NSTE-ACS patients who underwent a percutaneous DES implantation in Southern Medical University Zhujiang Hospital during 1st Feb,2013 to 31th Jan,2014. Among them,136 patients were male and the rest 45 were female.177 patients completed the following-up possessing 97.8% with 133 male patients and 44 female patients. NSTE-ACS, according to the situation when patients go into hospital.1.1 Diagnosis criteria:The diagnosis standard of NSTE-ACS provided by European society of cardiology in 2015.1.2 Exclusion criteria:Anemia(Hemoglobin is less than I3gr/dL for male,12gr/dL for female); Severe liver and kidney insufficiency; Malignant tumors; Active infections; Auto-immune diseases; Preganant women; Recent blood transfution.1.3 Data collection:(1). Research-related original data all came from standalized clinical record in Southern Medical University Zhujiang Hospital, including sex, age, case history like Diabetes, Hypertension, CHD and cerebrovascular diseases, body mass index(BMI), smoking and post-discharging medicine taking. (2). Laboratory examination:Get venous blood samples to have blood routine examination and test the level of high density lipoprotein cholesterol (HDLC), low density lipoprotein cholesterol(LDLC), the peak value of MB isoenzyme of creatinekinases(CK-MB), serum creatinine(Scr), HbAlc, NT-pro-BNP, eGFR[according to the tested Scr level and Modified Diet in Renal Disease(MDRD) formula:eGFR equals 186 multiplies the Scr level and then get divided by 88.41, it minus 1.154 multiplies age minus 0.203 (multiplies 0.742 when it comes to female patients)] etc. eGFR=186×(Scr/88.41)-1.154×age-0.203(female×0.742)etc.1.4 RDW Measure Category:Using the Sysmex XE-5000 full-automatic blood analysis meter of the Laboratory Department of Southern Medical University Zhujiang Hospital to test the RDW value and divide into high RDW group(88 cases) and low RDW(89 cases) according to the median value.1.5 PCI (Percutaneous Coronary Intervention) and Ultrasonic Cardiogram(UCG)1.5.1 All the patients adopt radial artery or femoral artery passage and the lesion site is observed from two mutually perpendicular transillumination position. In addition, more than two interventional cardiologists, with over 20 years of interventional treatment experience, are invited to make a reasonable judgement and assessment. Degree of coronary artery stenosis is represented by the narrowing degree of the inside diameter of coronary artery. Stenosis over 50% will be diagnosed with CHD. Counting numbers of lesion sites is based on 3 systems, those located in left anterior descending artery(LAD), left Circumflex branch(LCX), and right coronary artery(RCA). The Gensini score system is applied to assess the degree of lesion of coronary artery. It’s all up to the operator to decide interventional therapy strategies, stenting technique, stent selection, application of anticoagulant drugs such as Tirofiban Hydrochloride, Heparin, and low molecular heparin. A successful interventional therapy is characterized by a less-than-25% stenosis in the target blood vessel, and blood flows to the forward direction can be assessed as TIMI III grade. Patients are implanted with DES (sirolimus or Paclitaxel) after the interventional therapy.1.5.2 Transthoracic Echocardiography:Physicians in the Ultrasound Department of Southern Medical University Zhujiang Hospital use Siemens ACUSON Sequoia512 to make an assessment of the left ventricular ejection fraction(LVEF) with Simpson’s method.1.6 Following up:it is carried out by a specailly-assigned person in many ways. For example, out-patient following up, telephone following up on a regular basis and medical records. Deadline of the following up is 1st Feb,2015, covering 14.67±5.78 months’ following up time. We are about to write down the following-up time, clinical events and situation of post-discharg medicine taking. The terminal point contains all-caused mortality and the major adverse cardiac events(MACE) includes all-caused mortality, non-fatal myocardial infarction and blood reconstruction of target vesssels.1.7 Statistic approach:Apply SPSS20.0 statistic soft ware to analyze data. Continuous variable is remarked by X±S. Data obeyed to normal distribution use one-way ANOVA check while those belongs to abnormal distribution adopt Wilcoxon rank-sum test. Classified variables is remarked by percentage employing x2 or Fisher Concise Test to make a check. Kaplan-Meier Method is used to draw an accumulated survival curve with Log-rank method. The Cox Regression Model is applied to analyze all-caused mortality and risk factors of MACE with all the base-line data, crowd characteristics, clinical results getting in. Moreover, it’s necessary to estimate the hazard ratios(HR) and 95% confidence intervals(CI). When P<0.05, the difference is of statistic significance.2. Results2.1 Base-line data analysis: 181 match-condition patients have been adopted and there are about 177 patients (97.8%) who have completed following up. The average follwing-up time is (14.67±5.78) months. If we make a comparison between the base-line data of the two groups according to RDW, Platelet, situation of LVEF≤40% and BETA Block drugs, we’ll find the difference is of statistic significance(P<0.05) while the other varibles are of no statistic significance.(to Form 1)2.2 Comparison between following-up results: According the following-up results, it’s showed that all-caused mortality rate in the high RDW group is 12.5% to 3.4%(P=0.024) and the MACE occuring rate is 26.1% to 13.5%(P=0.006). And there is a statistic difference from that of low RDW group. The probality of blood reconstruction during the following-up period is 22.7% to 4.5%(P<0.05), which also shows a statistic difference.(to Form 2)2.3 Cox s proportional hazard regression model analysis: Apply Cox regression analysis to evaluate all-caused mortality and the predictive factors of MACE and make those base-line unbalanced factors be included into single factor analysis so as to let the single-factor analyzing results get included into multi-factor analysis. After correcting confounding factors like platelet, LVEF≤40% or Beta Block drugs, the high RDW group is still a predictive factor of all-caused mortality and occurrence of MACE. For the former, HR is 3.691, 95%CI is 1.028 to 13.245 and P equals 0.045.And for the latter, HR is 2.844, 95%CI is 1.316 to 6.149 and P equals 0.008. High RDW and LVEF≤40% are connected to mortality.(to Form 3 and 4)Kaplan-Meier curve have showed that the all-caused mortality rate and MACE occuring rate between the two groups have statistic significance with Log-rank P equaling 0.025 and 0.005 respectively). (to Figure 1 and 2)3. Conclusions:High RDW on admission is an independent predictor of long-term adverse clinical outcomes in patients with NSTE-ACS treated with DES.