Risk Factors Of Dilated Cardiomyopathy Complicated With Malignant Ventricular Arrhythmia

Objective: to analyze the risk factors of dilated cardiomyopath-y(DCM)combined with malignant ventricular arrhythmia(MVA),and to find the possible prevention and treatment targets,so as to provide reference for the clinical diagnosis and treatment of DCM combined with MVA.Methods: This study selected patients who were diagnosed with DCM in the Second Affiliated Hospital of Gui lin Medical University from January 2017 to June 2020.There were139 patients who met the inclusion criteri.The general baseline data(such as gender,age,smoking history,drinking history,etc.),biochemical data(such as liver and kidney function,electrolyte,nail function,etc.)and related examination results(such as electroca-rdiogram(ECG),Ultrasound cardiogram(UCG),24h-dynamic electrocardiogram(Holter)).The patients with DCM and ventricular arrhythmia(VA)were divided into three groups by Holter: group A(normal / accidental premature ventricular contraction(PVC)group,i.e.premature ventri-cular contractions<720 beats/24 hours),group B(frequent PVC gro-up,i.e.premature ventricular contractions>720 beats / 24 hours),and group C(polymorphous frequent PVC combined with non susta-ined ventricular tachycardia(NSVT)group),Univariate analysis and multivariate logistic regression analysis were used to explore the risk factors of MVA in patients with DCM.The area under the curve(AUC)value of Receiver operating characteristic curve(ROC),sensitivity and specificity were used to evaluate the predictive effect of each predictor in DCM combined with MVA.Results:The general baseline comparison of group A,B and C showed significa-nt difference in age(P<0.05),but there was no significant difference in gender,hospitalization times,smoking history,drinking history,atrial fibrillation and bundle branch block(P>0.05).Further pairwise comparison showed that there were significant differences in age between group A,group B and group C(P<.05).Comparing the clinical biochemical data of A,B and C groups,the overall difference of NT-pro BNP was statistically significant(P<0.05),while the other bio-chemical indexes had no statistical difference(P>0.05).Further pairwise-comparison showed that NT pro BNP in group A was significantly higher than that in group B and C,There were significant differences between the two groups(P<0.05).A,B,C three groups of the electrocardiogram indexes comparison,the overall difference of QRS duration and Q-T inter-val was statistically significant(P<0.05),while QTc had no statistical dif-ference(P>0.05).Further pairwise comparison shows that QRS duration of group C is significantly different from that of group A and B(P<0.05),and Q-T interval of group C is significantly different from that of group A(P<0.05).A,B,C three groups of the echocardiographic indexes comparison,the overall difference of LVEDD,LAS,RVD and LVEF was statistically significant(P<0.05),while IVSd and LVPWd had no statisticaldifference(P>0.05).Furthermore,the comparison of LAS and LVEDD among the three groups,and LVEF in group C was significantly higher than that in group A and group B,There were significant differences between the two groups(P<0.05).A,B,C three groups of Holter index comparison,the overall differences of SDNN,SDANN,RMSSD and pNN50 were statistically significant(P<0.05).Further pairwise comparison showed that there were statistically significant differences in SDNN and pNN50 among the three groups,and in SDANN and RMSSD between group A and group B and group C(P<0.05).(2)Multivariate logistic regression analysis showed that Age(OR = 1.063,95% CI: 1.019-1.108,P: 0.005),LAS(OR = 1.189,95% CI: 1.083-1.304,P<0.001),LVEDd(OR = 1.159,95% CI:1.055-1.273,P: 0.002),pNN50(OR = 1.108,95% CI: 1.053-1.166,P<0.001)were risk factors for MVA in DCM patients.(3)ROC curve was used to evaluate the predictive value of age,LAS,LVEDD and pNN50 on MVA of DCM patients.ROC curve showed that the best cutoff values of age,LAS,LVEDD and pNN50 were 52.5,46.5,63.5and 2.19 respectively.The areas under the curve(AUC)were 0.634,0.786,0.771 and 0.752,respectively.The 95%CI were 0.536~0.732,0.709~0.862,0.693~0.85 and 0.671 ~ 0.832,respectively.The sensitivity were 0.814,0.767,0.814 and 0.907,respectively.The specificity were 0.406,0.677,0.635 and 0.542,respectively.Conclusions:Old age,increased LAS,LVEDd and decreased heart rate variability may be the risk factors for DCM combined with MVA,which has certain predictive value.