No-reflow Risk Prediction And Perioperative Myocardial Protection In Primary PCI Patients With Acute Myocardial Infarction

Background and objective The mortality and disability rate of acute myocardial infarction(AMI)are high.At present,early primary percutaneous coronary intervention(PCI)is the most effective treatment,which can quickly open the infarct related epicardial artery(IRA),reduce the infarct size and significantly reduce the mortality of patients.However,a considerable proportion of patients with primary PCI still have hypoperfusion in myocardial tissue under the condition of epicardial coronary artery opening,that is,"no reflow"(NR)phenomenon,the fundamental reason of which is myocardial microcirculation obstruction(MVO).As a complication,NR increased the in-hospital mortality by 5 to 10 times.How to prevent and predict the occurrence of no-reflow in the early stage has become the focus and difficulty of cardiologists.Previous studies on no-reflow prediction model mainly focused on small sample size,single-center emergency interventional therapy,it is difficult to effectively screen patients who are really likely to have no-reflow.The scoring criteria of some models are complex,which is not conductive to clinical promotion,and may delay the screening of high-risk patients.The NR score,developed earlier by our team,was able to assess the risk of no-reflow simply and quickly before primary PCI,stratified patients at an early stage,and identified high-risk patients,but failed to clarify its predictive value for in-hospital deaths and out-of-hospital events.There is also a lack of similar reports in academic circles.On the basis of further verifying the model to predict intraoperative no-reflow events,this study focused on the in-hospital death and out-of-hospital major adverse cardiac events(MACE)of STEMI patients after emergency PCI treatment,and classified them according to time.To explore the predictive value of NR score model for postoperative adverse events in this kind of patients.As a comprehensive management strategy of no-reflow,the high-risk patients with no-reflow need to be given effective intervention measures during the perioperative period of primary PCI to protect the myocardium and improve the prognosis of patients.The perioperative no-reflow phenomenon of primary PCI can cause the second blow of the heart and significantly increase the mortality of patients.Early detection and drug intervention methods are difficult in the field.At present,adenosine,antithrombotic and other drugs used in clinical practice can improve the no-reflow to a certain extent.However,the effect is very small.Based on the systematic treatment characteristics of traditional Chinese medicine,it can play a role from a variety of mechanisms to achieve the effect of three-dimensional defense.The main components of Danhong injection are Salvia miltiorrhiza and safflower,which have multiple effects such as anti-ischemia,antithrombotic,antioxidant and so on.It is theoretically feasible to use Danhong injection in the prevention and treatment of no re:flow injury.Our team's previous work has concluded that Danhong injection can reduce myocardial injury during the perioperative period of PCI in patients with unstable angina pectoris.Therefore,this study used the no-reflow risk prediction model developed in the early stage to screen high-risk patients without reflow,and Cardiac magnetic resonance(CMR)was used as the evaluation intervention method.To observe the myocardial protective effect of Danhong injection during perioperative period of PCI,and to provide theoretical and practical basis for comprehensive prevention and treatment of no-reflow.MethodPart I Retrospective analysis was used to select 782 patients who were hospitalized in our hospital for primary PCI due to STEMI from June 2009 to October 2016.According to the criteria of inclusion and exclusion,a total of 782 patients were included.The patients were divided into high-risk group and low-risk group depending on the score of no-reflow prediction>10..To verify the predictive ability of this prediction model for no-reflow,multivariate survival regression analysis was carried out on the MACE in and out of hospital.Part II Selected patients who underwent primary PCI due to STEMI in our hospital and the affiliated Hospital of traditional Chinese Medicine of Capital University of Medical Sciences between March 2016 and February 2018.A total of 172 cases were selected according to the criteria of inclusion and exclusion,and were randomly divided into two groups according to the random table.One group was the intervention group,the group was treated with routine drug therapy+Danhong injection(40ml+ 5%glucose injection/0.9%saline 250ml,intravenous drip)before PCI on the basis of routine treatment of acute myocardial infarction.The Danhong injection was applied for 4-6 days after operation.The other group was the control group,which was treated with the same dose of normal saline on the basis of routine treatment of acute myocardial infarction,and continued to be used for 4-6 days after operation.Cardiac magnetic resonance imaging was performed during perioperative period(7±2 days).The main end point was the myocardial infarct size of delayed contrast-enhanced area.The secondary end point was the main adverse cardiac events observed by telephone and outpatient follow-up in 6 months after PCI.ResultsPart I Retrospective analysis of hospitalization data of patients with STEMI1.General medical history:There were 782 STEMI patients with primary PCI in our hospital.The average hospitalization time was 8(6,10)days.The patients were divided into two groups according to whether NR score>10 points.There were significant differences in age,sex,admission Killip grade,onset-emergency admission time,smoking history,hyperlipidemia history and diabetes history between the two groups(P<0.05).2.PCI treatment related index:There were significant differences in multi-vessel coronary artery disease,postoperative ventricular tachycardia or ventricular fibrillation and IRA balloon dilatation rate between the two groups.3.Incidence of no-reflow in TIMI:There was significant difference between the low risk group(3.9%),the high risk group(13.6%)and the high risk group was 3.5 times as much as the low risk group.4.Laboratory results:There were significant differences in Hemoglobin concentration(HGB),mean hematocrit(Hct),admission neutrophil count(Neu),glycosylated hemoglobin(HbAlc),total cholesterol(TC),triglyceride(TG),Low density lipoprotein cholesterol(LDL-C),troponin T(cTNT)of the peak value of perioperative period and the value of blood glucose in admission between the two groups(P<0 05).There was no significant difference in other laboratory indexes,5.left ventricular ejection fraction(LVEF),left ventricular end-diastolic volume(LVEDV)and left ventricular end-systolic volume(LVESV).6.Kaplan-Meier method was used to analyze the in-hospital and out-of-hospital survival curves of patients in low-risk group and high-risk group:Compared with the high risk group,the risk of MACE in the low risk group was significantly lower,the survival time was longer,and the difference was significant.7.Retrospective analysis of in-hospital and out-of-hospital follow-up events:Of the 852 patients with STEMI undergoing primary PCI,782 cases were followed up and 70 cases were lost,the rate of loss of follow-up was 8.2%.The total incidence of MACE in STEMI patients was 23.9%,including 12.6%in lowrisk group and 28.6%in high risk group.The total mortality rate was 11.8%,including 5.3%in hospital,6.5%in survival and discharge,1.3%in low risk group and 16.3%in high risk group.The incidence of MACE,all-cause mortality,psychogenic mortality and readmission rate due to severe heart failure in the low-risk group were significantly lower than those in the high-risk group,and there was significant statistical difference between the two groups.7.1 Multivariate COX proportional hazard regression for in-hospital events:In the analysis of the related factors of the incidence of MACE(cardiac death,non-cardiac death,recurrent infarction),the baseline variables were adjusted.The no-reflow prediction score>10,and multi-vessel coronary artery disease,ventricular tachycardia or ventricular fibrillation after operation are independent risk factors for the incidence of MACE in hospital(all-cause death and recurrent infarction),all-cause mortality in hospital and cardiac mortality in hospital.7.2 Multivariate COX proportional hazard regression analysis of out-of-hospital follow-up events:737 patients were followed up outside the hospital,229 cases in the low risk group and 508 cases in the high risk group.In the analysis of related factors,NR score>10,coronary artery disease,It is an independent risk factor for the incidence of out-of-hospital MACE(all-cause death and recurrent infarction,admission for severe heart failure,coronary artery revascularization),out-of-hospital all-cause mortality and out-of-hospital psychogenic mortality.7.3 Multivariate COX proportional hazard regression analysis of cumulative in-hospital and out-of-hospital events:In the correlation factor analysis,NR score>10 points,Multi-vessel coronary artery disease is an independent risk factor for cumulative MACE incidence(all-cause death and recurrent infarction,admission to hospital for severe heart failure,coronary artery revascularization),cumulative all-cause mortality and cumulative psychological mortality.In addition,postoperative ventricular tachycardia or ventricular fibrillation is a risk factor for cumulative all-cause mortality and cumulative cardiac mortality.8.Distribution of follow-up events:The peak periods of out-of-hospital MACE incidence and all-cause death in high-risk patients with NR score were followed up for 0?6 months and 24 months respectively.Part II Myocardial protective effect of Danhong injection during perioperative period of PCI on no reflow high risk patients with acute myocardial infarction undergoing primary PCI1.Among the 172 patients with high risk of no reflow,119 patients completed one CMR examination,including 99 cases in our hospital and 20 cases in the affiliated Hospital of traditional Chinese Medicine of Capital Medical University.2.The Myocardial Salvage Index in CMR,Danhong group was higher than that of the control group.Compared with the control group,the myocardial infarction area of Danhong group was smaller,the prevalence of microcirculation obstruction was less,and the left ventricular ejection fraction was increased,the difference was statistically significant.3.All the selected patients were followed up and 2 cases were lost.The clinical follow-up rate was 98.7%.Among the 3 dead patients,3 deaths were associated with myocardial infarction complications(heart failure after myocardial infarction;1 case in Danhong group and 2 cases in control group).After 6 months,the incidence of MACE in Danhong group was lower than that in control group.However,there was no significant difference in the incidence MACE between the two groups.Conclusion:1.The score of no reflow>10 was an independent predictor of the incidence of MACE in and out of hospital.2.This model has good discriminant ability,especially in the high risk patients with no reflow and in predicting the occurrence of no reflow and following up adverse events.3.The peak period of out-of-hospital MACE in patients who survived and discharged from hospital was about 0-6 months and 24 months after discharge.4.The perioperative application of Danhong injection in primary PCI of STEMI patients can reduce the infarct size,improve myocardial microcirculation obstruction and reduce the effect of myocardial injury.5.Cardiac MRI was used to objectively and quantitatively evaluate the effect of Danhong injection on myocardial infarction area and cardiac function,and to identify the no-reflow more sensitively.