Clinical Study Of Cardiac Remodeling And Prognostic Assessment Of Myocardial Infarction By Echocardiographic Technology And Plasma CfDNA

Ⅰ.Clinical study of cardiac remodeling and prognostic assessment of acute myocardial infarction by echocardiographic technology 1.The prognostic value of left atrial and left ventricular strain evaluated by two-dimensional speckle tracking imaging in left ventricular remodeling and outcome in patients after acute myocardial infarction Objective: We aimed to assess the clinical prognostic value of left ventricular global longitudinal strain(LVGLS)and peak atrial longitudinal strain(PALS)in patients after ST-segment-elevation myocardial infarction(STEMI)treated with primary percutaneous coronary intervention(PCI).Methods: The study enrolled 199 patients who underwent PCI for first STEMI.Conventional and 2D-STI were performed within 24 h after PCI.At 6-month and 18-month follow-ups,the patients were divided into the were divided into LV remodeling(LVR)group and non-LV remodeling(Non-LVR)group;and they were divided into the event(Event)group and event-free(Event-free)group.Multivariate Logistic regression model was used to analyze the predictive value of LVGLS and PALS on LV remodeling after AMI;Multivariate Cox model was used to analyze the predictive value of LVGLS and PALS on major adverse clinical events after AMI.The predictive value of PALS,LVLGS and PALS combined with LVLGS for the prognosis after AMI was evaluated by receiver operating curve(ROC),and the area under the ROC curve(AUC)was calculated to judge the diagnostic efficacy of each indicator.The predictive value of PALS,LVLGS and PALS combined with LVLGS for the prognosis after AMI was evaluated by receiver operating curve(ROC),and the area under the ROC curve(AUC)was calculated to judge the diagnostic efficacy of each indicator.Results: In logistic regression,adjusted clinical and echocardiographic parameters,diabetes mellitus,LVGLS and PALS were independently associated with LV remodeling(P<0.05,respectively).The best cutoff values of LVGLS and PALS for LV remodeling were-11.3%(AUC: 0.86,sensitivity: 71.4%,specificity: 84.0 %)and 28.9 %(AUC: 0.83,sensitivity: 72.7%,specificity: 87.8%).However,PALS did not add significant incremental value beyond LVGLS in the prediction of LV adverse remodeling(AUC increased from 0.86 to 0.91;P=0.24).In a multivariate Cox proportional hazards model,and diabetes mellitus,LVGLS and PALS were independently associated with the composite events(P<0.05,respectively).The best cutoff values of LVGLS and PALS for adverse clinical events were-12.3%(AUC: 0.86,sensitivity: 95.7%,specificity: 67.0%)and 28.9%(AUC: 0.83,sensitivity: 88.1%,specificity: 65.2%).However,PALS did not add significant incremental value beyond LVGLS in the prediction of the composite event(AUC decreased from 0.86 to 0.83;P=0.69).Conclusions: Both PALS and LVGLS evaluated by two-dimensional speckle tracking imaging provided independent prognostic value for LV remodeling and adverse clinical outcomes after STEMI.However,the ability of the combination of PALS and LVGLS to predict LV remodeling and clinical outcomes might not be superior to that of a single indicator.Therefore,in the evaluation of echocardiography of AMI patients,focusing on the PALS or LVLGS can quickly and effectively stratify the degree of risk,which helped clinical optimization of treatment strategies and improve prognosis.2.The prognostic value of right ventricular function evaluated by two-dimensional speckle tracking and three-dimensional echocardiography in patients with acute inferior myocardial infarctionObjective: This study aimed to assess the recovery of the right ventricular systolic function in patients with acute inferior myocardial infarction(INFMI)during hospitalization by using real-time three-dimensional echocardiography(RT-3DE)and two-dimensional speckle tracking imaging(2D-STI),and to investigate the prognostic value of the right ventricular systolic function for prediction of clinical outcome in patients after INFMI.Methods: The study enrolled 87 patients who underwent primary percutaneous coronary intervention(PCI)for first INFMI.Echocardiography were performed at within 24 hours after admission and before discharge(4.5±2.1 days after PCI),and right ventricular function was assessed by RT-3DE and 2D-STI.The patients were followed-up for 13±2.3 months after discharge,and they were divided into the event group and event-free group according to whether clinical events(including all-cause death,non-fatal reinfarction,or hospitalization for heart failure)occurred.Multivariate Logistic regression model was used to analyze the predictive value of right ventricular function on major adverse clinical events after INFMI.Results: Compared with baseline(TTE1),the tricuspid annular lateral wall peak systolic velcity(S’),tricuspid annular systolic excursion(TAPSE),right ventricular global longitudinal strain(RVGLS),free wall basal segment(FW-BAS),free wall mid segment(FW-MID)and septal basal segment(SEP-BAS)of INFMI group were better at discharge(P<0.05,respectively),and right ventricular global ejection fraction(EF-global),inflow EF(EF-inflow)and body EF(EF-body)were higher at discharge(P<0.05,respectively),while right ventricular inflow end diastolic volume(EDV-inflow)and body EDV(EDV-body)were lower at discharge(P<0.05,respectively).The age,Killip grade ≥ 2,peak of CK-MB,NT-pro BNP,EDV-inflow(TTE 2)and EDV-body(TTE 2)of the Event group were higher than those of the Event-free group(P<0.05,respectively),while S’(TTE2),RVGLS(TTE1 and TTE2),FW-MID(TTE1),EF-inflow(TTE 2)and EF-body(TTE 2)were lower than those of the Event-free group(P<0.05,respectively).Multivariate regression analysis showed that RVGLS(TTE2)、EF-inflow(TTE2)and EF-body(TTE2)were the independent predictors of clinical outcome after INFMI;ROC displayed that the optimal cut-off for RVGLS(TTE2)was-13.5% [area under curve(AUC):0.833,sensitivity: 83%,specificity: 69%]、51.5%(AUC: 0.728,sensitivity: 59%,specificity: 83%)and 43.5%(AUC: 0.811,sensitivity: 59%,specificity: 92%).Conclusions: There were significant improvements in right ventricular myocardialcontractility and function in patients with acute INFMI at discharge,indicating the impaired RV systolic function was reversible and recovered quickly.In addition,RVGLS(TTE2),EF-inflow(TTE2)and EF-body(TTE2)were the independent predictors of clinical outcome after INFMI.Therefore,this study highlighted the need for pre-discharge echocardiography in patients after myocardial infarction,and closer follow-up of patients with persistent right ventricular dysfunction might be useful,and RVGLS-TTE2 might be more conducive to identifying INFMI high-risk patients with poor prognosis.3.Assessment of right atrial volumes and fucntions in patients with acute inferior myocardial infarction by two-dimensional speckle tracking and three-dimensional echocardiography Objective: This study aimed to quantitatively evaluate right atrial phase volumes and function in patients with acute inferior myocardial infarction(IMI)with or without right ventricular myocardial infarction(RVMI)by using real-time three-dimensional echocardiography(RT-3DE)and two-dimensional speckle tracking imaging(2D-STI).Methods: The study enrolled 86 patients who underwent primary percutaneous coronary intervention(PCI)for first INFMI.All the patients were divided into INFMI group(55 cases)and INFMI+RVMI group(31 cases)based on whether they had RVMI.30 patients who matched the age and gender of the INFMI patients and had normal coronary angiography results were selected as the control group.Right atrium phase volume was evaluated by RT-3DE,including right atrium maximal volume(RAVmax),right atrium minimal volume(RAVmin)and right atrium presystolic volume(RAVpre).Right atrial function was evaluated by 2D-STI,and the following three parameters related to right atrial strain: right atrial myocardial positive strain(LSpos),negative strain(LSneg),and the sum of the absolute values of the two(LStot).The correlation between tricuspid annular systolic excursion(TAPSE),E/e’,right ventricular global longitudinal strain(RVGLS)and right atrial parameters were analyzed.The receiver operating curve(ROC)was used to determine the best diagnostic cutoff for RT-3DE and STI parameters to predict acute INFMI combined with RVMI.Results: Compared with the control group and the INFMI group,right atriummaximal volume index(RAVmax I),right atrium minimal volume index(RAVmin I),right atrium presystolic volume index(RAVpre I),total stroke volume index(TSVI)and active stroke volume index(ASVI)of INFMI+RVMI group were significantly increased(P<0.05,respectively),while right atrium passive emptying fraction(PEF),LStot and LSpos significantly reduced(P<0.05,respectively).LStot and LSpos were positively correlated with TAPSE and RVGLS(r=0.352,r=0.551;r=0.312,r=0.5537;P<0.001,respectively),and negatively correlated with E/e’(r=-0.490,r=-0.590;P<0.001,respectively).RAVmax I、RAVmin I and RAVpre I were negatively correlated with TAPSE and RVGLS(r=-0.336,r=-0.629;r=-0.346,r=-0.588;r=-0.383,r=-0.601;P<0.001,respectively),and positively correlated with E/e’(r=0.526,r=0.456,r=0.502;P<0.001,respectively).The area under the ROC curve of RAVmax I was the biggest to predice INFMI with RVMI,with the optimal cut-off for 27.5 ml/m2(sensitivity:74%,specificity: 80%).Conclusions: Our study found that the use of RT-3DE and 2D-STI detected the increase of the right atrium phase volumes and the myocardial damage in patients with acute INFMI at an early stage.RAVmax I measured by RT-3DE could be used as a surrogate indicator for judging whether IMI was combined with RVMI,which provided a strong basis for early clinical diagnosis and early treatment.Ⅱ Survival outcome cardiac function improvement correlate with the level of cell-free circulating DNA in patients with acute myocardial infarction Objective: Acute myocardial infarction(AMI)is a critical condition that results in cellular damage that releases nuclei content into the blood circulation.Plasma free cell DNA(cf DNA)content can be used to measure the degree of cell damage.This study aims to explore the predictive value of cf DNA on the survival outcome and cardiac function improvement of AMI patients.Methods: The study enrolled 150 patients who underwent primary percutaneouscoronary intervention(PCI)for first ST-segment-elevation myocardial infarction(STEMI).50 patients who matched the age and gender of the STEMI patients and had normal coronary angiography results were selected as the control group.The fresh plasma samples were collected from all enrolled subjects for 7 consecutive days.Measurements of cf DNA content used a direct fluorescence assay.Patients were also serially monitored to correlate with post disease status.The rate of change of cf DNA taken as a ratio of measurements between Day 1 to 7 and the baseline value was computed.The patients were followed-up for 90 days,and they were divided into the survival group and non-survival group according to survival status;and divided into improvement group and non-improvement group according to whether △LVEF ≥5%。We compared cf DNA content,coefficient of variation(CV)and rate of change of the two groups.A receiver operating characteristic(ROC)curve was constructed to determine the ability of cf DNA to predict survival outcomes and cardiac function improvement.Results:Mean concentration of cf DNA with disease individuals was 5.93 times higher than healthy controls(P< 0.05).A stark contrast in trending was observed between healthy and AMI individuals.Patients were divided by their survival status within a 90-day period.Receiver operating characteristic(ROC)curve analysis showed that the cf DNA change rate predicted the survival state and area under the curve of cardiac function improvement after AMI,with the best cut-off values of 2.5(sensitivity 81.5%,specificity 74.0%),2.65(sensitivity 50.0%,specificity 100%).Conclusions: cf DNA was strongly associated with AMI and serial measurements during early disease onset can be an early prognostic factor for patients.