Effect Of Right Ventricular Apical Pacing On Atrial Remodeling And Clinical Study Of New Onset Atrial Fibrillation

Objective: To investigate the effect of right ventricular apical pacing on atrial remodeling in pacing dependent and independent patients,and to predict the risk factors of new atrial fibrillation after pacemaker implantation;Through the analysis of follow-up data,comparing the differences of cardiac indicators in patients with different years and different indications of pacemaker implantation,and the changes of cardiac function and the risk of new-onset atrial fibrillation were evaluated;Furthermore,to explore the correlation between P wave dispersion(Pd),P wave peak time(PWPT)and the cumulative ventricular pacing(CumVP%),and to test the effectiveness of Pd and PWPT in predicting the occurrence of atrial fibrillation after right ventricular apical pacing,so as to lay a theoretical foundation for screening high-risk groups of new-onset atrial fibrillation after pacemaker implantation.Methods: Our study selected 80 patients who had no history of atrial fibrillation,and put the Sick sinus syndrome(SSS)or Atrioventricular block(AVB),especially the complete AVB,as the indication of pacemaker implantation,they all implanted the double chamber pacemaker(DDD)for the first time and regularly followed up in the outpatient and cardiovascular inpatient areas of the Affiliated Hospital of Inner Mongolia Medical University from January1,2011 to December 31,2021.We collected the detailed clinical data of the included medical records before and after pacemaker implantation that meet the inclusion and exclusion criteria,including the general information of the patients,the relevant laboratory examinations,12-lead electrocardiogram,echocardiography and the data of pacemaker program control which collected at the last follow-up.Patients were divided into different groups according to whether they had new-onset atrial fibrillation,whether they were ventricular pacing dependent,pacemaker implantation years and pacemaker implantation indications.The differences of the relevant indexes were compared,the risk factors of new-onset atrial fibrillation after pacemaker implantation were analyzed,and the relationship between the CumVP% and Pd,PWPT under right ventricular apex pacing was compared in detail.Results: 1.Groups were divided according to whether there is new-onset AF after pacemaker implantation,the clinical baseline data before treatment between the two groups are basically the same(P > 0.05),which is comparable;At the last follow-up after operation,there was still no significant difference between the two groups in general conditions(P > 0.05).The C-reactive protein(CRP),P-wave dispersion(Pd),P-wave peak time(PWPT),left atrial diameter(LAD)and the CumVP% in the group with AF were significantly higher than those in the group without AF,Low density lipoprotein cholesterol(LDL-C)was lower than the group without AF(P < 0.05),and there was no significant difference between other indexes(P > 0.05).Further analysis by receiver operating characteristic curve(ROC): the area under the curve(AUC)predicted by Pd was 0.755(95% CI:0.632-0.878;P=0.01),and the AUC of PWPT was 0.773(95% CI: 0.654-0.891;P=0.00);2.Grouped by CumVP%,the ventricular pacing dependent group had more patients with new-onset atrial fibrillation(P<0.05),N-terminal pro brain natriuretic peptide(NT-proBNP),CRP,LAD,left ventricular end diastolic diameter(LVEDD),P maximum(Pmax),Pd,PWPT which in ventricular pacing dependent group were significantly higher than the other,while LDL-C was more lower(P<0.05);3.Divided into three groups according to the years of pacemaker implantation,it was found that with the extension of pacing time,the indexes of NT-proBNP,CRP,LAD,LVEDD,Pmax and Pd increased,while the left ventricular ejection fraction(LVEF)decreased(P<0.05),there was no significant difference among the other indexes in the three time periods(P>0.05);4.According to the indication of pacemaker implantation,the indexes of NT-proBNP,LAD,LVEDD,Pmax,Pmin,Pd and PWPT in AVB group were higher than those in SSS group(P<0.05),there was no significant difference in other indexes(P>0.05);5.Pearson correlation analysis of Pd,PWPT and CumVP% in 80 subjects at the last follow-up showed that Pd and PWPT were significantly positively correlated with CumVP%(r=0.301,P=0.007)and(r=0.208,P=0.009).Conclusion: 1.The increase of NT-proBNP,CRP,LAD,Pd,PWPT and CumVP% are related to new-onset atrial fibrillation after pacemaker implantation,which are the risk factors for atrial fibrillation;2.Right ventricular apical pacing with a high proportion of ventricular pacing will cause atrial electrical remodeling and structural remodeling,and aggravate the risk of new-onset atrial fibrillation;3.With the extension of pacemaker implantation years,the validity of atrial remodeling increases,the cardiac function of patients decreases gradually,and the risk of new-onset atrial fibrillation is higher;4.Patients with high atrioventricular block are often accompanied by a high percentage of cumulative ventricular pacing,and have a high risk of new-onset atrial fibrillation;5.With the increase of CumVP%,Pd and PWPT also increase accordingly,suggesting that high percentage of ventricular pacing will cause more significant atrial remodeling and increase the risk of atrial fibrillation.