Correlation Between Circadian Rhythm And Left Ventricular Function In Idiopathic Premature Ventricular Complexes Of Different Burdens

Objective: To investigate the correlation between circadian rhythm of idiopathic premature ventricular complexes(PVCs)with different burdens and left ventricular function.Methods: This is a single-center retrospective study.A total of 180 hospitalized patients diagnosed idiopathic PVCs seen at The First Affiliated Hospital of Xinjiang Medical University from January 1,2019 to December 31,2020 were included.According to burdens of PVCs,patients were divided into low burden group(<10%),medium burden group(10%～20%),and high burden group(>20%).Patients were divided into daytime group and nighttime group according to the occurrence time of PVCs: daytime group:daytime PVCs(which occurred from 06:00 to 18:00)accounted for more than50% of all-day PVCs;Night group: night PVCs(occurring from 18:00 to 06:00the next day)accounted for more than 50% of all day PVCs.Basic patient data,test indexes,echocardiography,dynamic electrocardiogram and other indexes were collected,analyzing baseline data and compared between groups,including left atrial diameter(LAD),right atrial diameter(RAD),interventricular septum(IVS),left ventricular end diastolic diameter(LVEDD),right ventricular diameter(RVD),left ventricular ejection fration(LVEF),cardiac stroke volume(SV),left ventricular fractional shortening(LVFS)and other cardiac function indicators.The relationship between PVCs burden,circadian rhythm,age,body mass index(BMI),sex,drug therapy,hemoglobin(Hb),aspartate aminotransferase(AST),creatinine(Cr),triglycerides(TG),total cholesterol(TC),high density lipoprotein(HDL),low density lipoprotein(LDL),lipoprotein a[LP(a)],glycated hemoglobin A1c(Hb A1c)and left ventricular function was analyzed by multiple linear regression method.Using receiver operating characteristic curve(ROC)to analyze the cutoff value of PVCs burden with normal low LVEF(50%<EF<55%)and the sensitivity and specificity of diagnosis with this cutoff value.Results:1.Compared with the low,middle and high burden group,there were no significant differences in LAD、RAD、RVD、IVS and SV(P>0.05),but there were significant differences in LVEDD,LVEF and LVFS(P<0.05).The average level of LVEDD in high burden group is higher than that in low and medium burden group,and the average levels of LVEF and LVFS are lower than those in low and medium burden group.2.There was no statistically significant difference in all cardiac function indexes between the daytime group and the nighttime group(P>0.05).3.Multiple linear regression analysis showed that PVCs burden had significant linear effects on LVEF and LVEDD respectively(P<0.05),and PVCs burden was negatively correlated with LVEF and positively correlated with LVEDD.BMI is positively correlated with LVEDD.Compared with women,men are more likely to have LVEDD enlargement,and the LVEDD enlargement of men is 2.5 times that of women.4.ROC curve analysis indicated an Area Under Curve score(AUC)of0.812,and the use of a PVCs burden cutoff value of 7.5% gave an 81.2%chance of diagnosing a patient with a normal low LVEF,with a sensitivity of88.9% and a specificity of 62.6%.Conclusion:1.Idiopathic PVCs with moderate or high burden are more likely to lead to a decrease in LVEF and LVFS and an enlargement of LVEDD.2.Idiopathic PVCs showed circadian rhythm variation,but PVCs in the daytime and nighttime groups had little effect on left ventricular function.3.PVCs burden is the influencing factor for the decrease of LVEF and LVFS,while PVCs burden,BMI and male are the influencing factors of LVEDD enlargement.4.When the patient’s PVCs burden is 7.5% or higher,it may lead to the decrease of LVEF,so it is necessary to treat and follow up this group of people.