Correlation Between Ventricular Tachycardia/fibrillation And Functional SYNTAX Score And Risk Assessment Model For Predicting Ventricular Tachycardia/fibrillation In Patients With Acute Myocardial Infarction

Background and ObjectiveAcute myocardial infarction(AMI)is a serious type of CHD in coronary heart disease,and it is the main cause of death and disability.Ventricular tachycardia(VT)and ventricular fibrillation(VF)are the most common types of arrhythmia in patients with AMI,mostly in the acute or subacute phase of MI.There are many studies have shown that patients with AMI and VT/VF often indicate long-term hospitalization and a long-term poor prognosis.Therefore,it is essential to identify AMI patients with increased risk of VT/VF in clinical work.Although many studies have described the risk factors of VT/VF after AMI in recent years,the relationship between the severity of coronary artery disease and the occurrence of VT/VF in AMI patients is still unclear.Secondly,although recent studies have analyzed the risk assessment models for the occurrence of VT/VF after AMI,but they neglect the important factor of the severity of coronary artery disease and the clinical variables such as blood biochemical indicators.Therefore,it is necessary to analyze the severity of coronary artery disease and common blood biochemical indicators,and other important clinical factors and establish a new VT/VF warning model.SYNTAX score(SS)is an anatomical scoring system that can indicate the severity of coronary artery lesions according to the number of lesions,their functional role,location,and complexity.It has guiding significance for the best strategy guide for revascularization.Fractional flow reserve(FFR)is an effective index to assess the degree of coronary ischemia.the concept of the functional SS(FSS)recalculating the SS after counting only ischemia-producing lesions with FFR?0.8 was developed.FSS was proved to have a better prognostic implication compared with classic SS.The strategy of performing percutaneous coronary intervention(PCI)in non-infarct-related coronary artery lesions(non-IRA)remains controversial.So far,using FFR to guide the intervention strategy of non-IRA has proven to be effective.But the clinical utility of FFR is still infrequent in real-world setting,due to equipment and drug costs,physician preferences,and the risk of related complications.Progress in angiography-derived FFR such as caFFR can reduce these limitations by calculation of functional parameters in a simpler and rapid way.Whether it is possible to use caFFR instead of FFR to guide the non-IRA treatment strategy of AMI patients,there is no relevant research elaboration.The purpose of this study is to investigate the relationship between the SS/FSS and the occurrence of VT/VF after AMI.And the second aim is to establish a new VT/VF risk assessment model which has further accuracy and applicability than other model.Finally,this study intends to explore the correlation between caFFR/FSScaFFR and the long-term prognosis of AMI patients,and conduct subgroup analysis in AMI patients with multivessel disease to evaluate the clinical utility of caFFR.MethodsWe retrospectively enrolled AMI patients who were hospitalized in Nanfang Hospital of Southern Medical University from July 2017 to July 2020 and collected their baseline clinical,demographic characteristics,medical history data,routine blood biochemical tests,and echocardiographic data.The SS of the patient's coronary artery were calculated based on the angiography data.The patient's coronary caFFR was analyzed by Suzhou Runmed Medical Technology Co.,Ltd.,and then the functional SYNTAX score based on caFFR was calculated.VT/VF was defined as:(1)Persistent ventricular tachycardia lasting more than 30s or requiring drugs or treated by electrical cardioversion;(2)ventricular fibrillation.Follow-up data are obtained through telephone follow-up and hospital electronic medical records.The main endpoint is major adverse cardiovascular events(MACE).Univariate and multivariate logistic regression were used to evaluate the correlation between SS/FSS and the occurrence of VT/VF after AMI.Univariate and multivariate COX regression were used to analyze the independent predictors of MACE.Then,the stepwise multivariate Logistic regression analysis was used to screening the predictors of VT/VF after AMI,and the nomogram model was constructed through the R language rms package.Finally we used the Hosmer-Lemeshow test,bootstrap method,and ROC analysis to verify its accuracy internally.Results1.There was no significant correlation between SS and VT/VF(p=0.069).FSS is an independent risk factor for VT/VF after AMI(p<0.001,OR:1.054,95%Cl:1.023-1.088).2.ROC analysis showed that both SS and FSS had significant statistical significance on the predictive ability of VT/VF(p<0.001),and the area under the curve(AUC)values were 0.695 and 0.759,respectively.FSS is better than SS in predicting VT/VF.Delong test showed that the two ROC curves are statistically different(p<0.001).3.In the median follow-up period of 22-month,FSS was an independent predictor of MACE in AMI patients(p<0.001,HR:1.046,95%CI:1.023-1.069).The residual FSS(rFSS)is also an independent predictor of the MACE of AMI patients.4.The nomogram to predict VT/VF after AMI was developed,which included systolic blood pressure,STEMI,WBC,diuretics,and FSS.The uncorrected C statistic with the actual curve is 0.901,and the bootstrap-corrected C statistic is 0.890.5.Among AMI patients with non-ischemic-non-IRA,the incidence of MACE in the non-IRA revascularization group was not significantly different from the non-revascularization group(6.7%vs 7.7%).6.In AMI patients with at least one ischemic-non-IRA,the incidence of MACE in ischemic-non-IRA revascularization group was higher than non-revascularization group(26.2%vs 16.2%),but there was not statistically significant.However,the more severe the postoperative ischemic state(number of post-PCI-e ischemic-vessels,rFSS),the worse the prognosis.After excluding the interference of confounding factors,there is still significant statistical significance.7.Among AMI patients with non-IRA revascularization,the incidence of MACE in patients of ischemic-non-IRA revascularization group was higher than non-ischemic-non-IRA revascularization group(26.2%vs 13.3%),but there was no statistics significance.8.Among AMI patients without non-IRA revascularization,the incidence of MACE in patients of ischemic-non-IRA group was significantly higher than non-ischemic-non-IRA group,which was statistically significant(18.4%vs 7.6%).After excluding the interference of confounding factors,there is still significant statistical significance(p=0.021,HR:1.555,95%CI:1.070-2.261).Conclusion1.FSS based on caFFR is an independent risk factor for VT/VF after AMI.At the same time,FSS and rFSS are independent predictors of the prognosis of AMI patients.2.The nomogram to predict VT/VF after AMI was developed,which included systolic blood pressure,STEMI,WBC,diuretics,and FSS.And internal verification shows that the nomogram has a good predictive performance.3.For AMI patients with multivessel vessel disease,revascularization of nonischemia-non-IRA(caFFR?0.8)will not significantly improve the prognosis of the patients.