The Clinical Research About Acute Myocardial Infarction And Coronary Collateral Circulation

AimChapter one:to evaluate the imaging features of coronary collateral circulation(CCC)in acute ST-segment elevation myocardial infarction(STEMI)with acute total occlusion(ATO)of only one epicardial coronary artery;Chapter two: to investigate whether the ratio of triglyceride to high-density lipoprotein cholesterol(TG/HDL ratio)is an independent risk factor for poorly-developed CCC in elderly STEMI patients with ATO of only one major epicardial coronary artery;Chapter three: to investigate the effects of CCC and other factors on all-cause mortality in elderly STEMI patients with ATO of only one epicardial coronary artery and successful primary percutaneous coronary intervention(PCI)within 12 hours of onset;Chapter four: to evaluate the role of miRNA in the diagnosis of non-ST-segment elevation myocardial infarction(NSTEMI)and monitoring adverse events.MethodsChapter one:we collected 209 patients combined STEMI with ATO and 80 patients with chronic total occlusion(CTO).All patients had only one major epicardial coronary artery occlusion.According to the Rentrop classification method(grade 0,1,2,3),the grades of ipsilateral and CCC associated with infarcted vessels was evaluated,and the higher grade between ipsilateral and contralateral CCC was considered as the final grade of the CCC of the occluded coronary artery.The patients with ATO were divided into 4 groups according to the onset time,the corresponding onset time of the first,second,third and forth group were ?3h,3-6h,6-12 h,12-72 h,respectively.The patients with CTO was defined as the fifth group.And the chi-square test was used to compare the grades of CCC between the five groups,between different occluded coronary arteries,between different types of coronary dominance,and between different conditions of whether the anterior descending branch(LAD)crossing the apex or not.The Kendall's tau-b method was used to analyze the correlation of the grades of CCC and onset time;Chapter two:as a retrospective case-control study,elderly patients(age ? 60 years)with both STEMI and ATO(n=346)were classified as having either poorly-or well-developed CCC(Rentrop grade 0-1 and 2-3,respectively).The ratio of TG/HDL was calculated according to the detected levels of TG and HDL.TG/HDL ratio between the two groups was compared by Student t test,and multivariate Logistic regression analysis was performed to identify risk factors for poorly-developed CCC.The receiver operating characteristic(ROC)curve analysis was used to determine the optimal cutoff value for the TG/HDL ratio for prediction of poorly-developed CCC;Chapter three:a total of 346 elderly STEMI patients with ATO who successfully underwent primary percutaneous coronary intervention(PCI)were enrolled in this study.The patients were divided into two groups as poorly-developed CCC group(Rentrop grade 0-1)and well-developed CCC group(Rentrop grade 2-3)according to Rentrop classification.The patients were followed up for 12 months.Successful standard of primary PCI was defined as postoperative blood flow to myocardial infarction thrombolytic therapy(TIMI)level 3.Logistic regression analysis was used to determine whether the poorly-developed CCC as the independent predictor of myocardial blushing grade(GMB)3,using of IABP pump and killip grade?2 or not.Univariate analysis(Kaplan-Meier and Log-Rank sequence test)screening related factors for death,using Cox regression analysis to identify factors that have significant impacts on death;Chapter four:a total of 145 NSTEMI patients and 30 healthy volunteers with no history of cardiovascular disease(CVD)were recruited.MiRNA levels in plasma were serially measured during disease manifestation and treatment phase.Levels of multiple candidates(miR-1,miR-133,miR-208,miR-499)were analysed.The levels of each miRNA were directly compared between NSTEMI patients and healthy volunteers.Differences in the levels of each miRNA and HS-cTnT in NSTEMI patients were also compared.ResultsChapter one : compared with that in the fifth Group(CTO),Rentrop grades(including ipsilateral,contralateral,and final grades)in the first four groups(ATO)were significantly lower.Compared with that in the forth group,ipsilateral and contralateral Rentrop grades in the first three groups were not statistically difference,but there was a significant difference in the final grade.The longer the onset time,the higher the Rentrop grade of CCC.There was a strong negative correlation between the composition ratio of “Rentrop grade 1” and the onset time,r=-0.506,P<0.001.There was no significant difference in the ipsilateral Rentrop grades between different occluded vessels.But there was a significant difference in the contralateral and final Rentrop grades between different occluded vessels.The Rentrop grade was the highest when right coronary(RCA)occluded,the second when LAD occlusion occlude,and the lowest when left circumflex branch(LCX)occluded.There were no significant differences in the ipsilateral,contralateral and final Rentrop grades for the different types of coronary dominance,and for whether the anterior descending branch crossing the apex or not;Chapter two:the TG/HDL ratio was significantly higher in patients with poorly-developed CCC than that in patients with well-developed CCC [2.88±2.52 vs 1.81±1.18,P<.001].In multivariate Logistic regression analysis,higher TG/HDL ratio [OR1.789,95%CI1.346-2.378,P<.001] and presence of LCX occlusion [OR6.235,95%CI2.220-17.510,P=.001] were emerged as independent positive predictors of poor development of CCC,whereas presence of RCA occlusion [OR0.474,95%CI0.265-0.850,P=.002] and onset time [OR0.693,95%CI0.620-0.775,P<.001] were found as negative indicators.The optimal cut-off value of TG/HDL ratio was found as 1.58 in ROC analysis,which yielded an area under the curve value of 0.716 [95%CI0.654-0.778,P<.001] and demonstrated a sensitivity of 80.9% and a specificity of 59.3% for prediction of poorly-developed CCC;Chapter three:we defined Killip classification ? 2,using of IABP,postoperative MBG 3 as the dependent variables,and age,occlusion of coronary artery,onset time,preoperative thrombolysis,TG level,HDL level,and well-developed collateral circulation(1=Yes,0=No)as independent variables.Multivariate Logistic regression analysis showed that CCC was an independent factor for predicting Killip classification? 2,using of IABP and postoperative MBG3.All patients were followed up for 12 months,of which 52 patients(15.0%)were lost,and 19patients(5.5%)died.Univariate analysis(Kaplan-Meier and Log-Rank sequence test)suggested that CCC had a significant impact on death.(p=0.046),however,multivariate analysis(Cox regression analysis)suggested that there was no statistically significant effect on the mortality of CCC after exclusion of other confounders(p=0.089).For every 1 hour increase of onset,the mortality increased by 26.9%,and the mortality of patients with Killip grade ? 2 was 8.287-fold compared with that of killip grade 0-1,and 8.25-fold of patients older than 75 years old compared with that of 60-75,and 5.7%-fold of patients with MBG 3 compared with that with MBG 0-2;Chapter four:cardiac related miRNA levels demonstrated significantly increase compared with healthy controls.MiR-499 exhibited the highest elevation with more than 6.03-fold change compared with healthy participants.Hs-cTnT measurements were in good agreement to miRNA relative expressions.In serial measurements,miR-499 demonstrated large fluctuations and couldbe linked to the secondary complications.In contrast,miR-133 showed insignifcant variations in mean levels during serial sampling.ConclusionChapter one : for patients with both STEMI and ATO,according to coronary artery angiography,coronary occlusion time has a great impact on grades of CCC.The longer the occlusion time,the higher the Rentrop grade(even in the acute phase of STEMI),but the composition ratio of Rentrop grade 1 was strongly negatively correlated with occlusion time: the longer the occlusion time,the lower the composition ratio of Rentrop grade 1.At the same time,occluded coronary artery also had a great influence on the Rentrop grades of CCC.Rentrop grade was the highest when RCA occluded,the second when LAD occluded,and the lowest when LCX occluded.Generally,the Rentrop grades of ipsilateral CCC was lower than that of contralateral CCC;Chapter two:TG/HDL ratio is an independent risk factor for predicting poor development of CCC in elderly patients with STEMI and ATO;Chapter three:for elderly STEMI patients with only one epicardial coronary artery occlusion and successfully undergoing primary PCI within 12 hours of onset,the well-/poorly-developed CCC in the acute phase of AMI has no direct significant impact on all-cause mortality for 12 months of follow-up.But patients with well-developed CCC have higher rates of MBG 3 after primary PCI,and the lower rates of killip grade ? 2,which indicating that well-developed CCC still has a indirect beneficial effect on prognosis.Moreover,the longer the onset time and the older the age,the higher the mortality;Chapter four:miRNAs are sensitive biomarkers for NSTEMI patients for disease detection and treatment monitoring.The diagnostic performance of miR-1 for NSTEMI was comparable to that of hs-cTnT,while the diagnostic performance of miR-133,miR-208 and miR-499 was better than that of hs-cTnT,of which miR-499 had the highest diagnostic performance,miR-499 could well monitor the occurrence of NSTEMI adverse events.