Follow-up Analysis Of New-onset Atrial Fibrillation After Right Ventricular Mid-septal Pacing And Right Ventricular Apex Pacing

Background Right ventricular apex pacing(RVAP)in previous clinical studies have confirmed that the disadvantages of pacemaker postoperative adverse clinical response,Right ventricular mid-septal pacing(RVMSP)in clinical practice is feasible,which have higher clinical safety than RVAP.Objective To compare the characteristics and influencing factors of new-onset atrial fibrillation after pacemaker implantation in right ventricular apex pacing group and mid-septal pacing group.Methods A single-center,case review study was conducted on patients with permanent dual-chamber pacemaker implantation in the heart center of the first hospital of lanzhou university.The right ventricular mid-septal pacing group(RVMSP group)was defined as the study group,and the right ventricular apex pacing group(RVAP group)as the control group.The pacing position was determined by X-ray,echocardiogram and electrocardiogram.Baseline data of the two groups and long-term follow-up results of postoperative new-onset atrial fibrillation were analyzed and relevant risk factors were assessed.Results The only clinical outcome event in this study was atrial fibrillation after pacemaker implantation.In this study,a total of 317 cases were selected after strict inclusion criteria and exclusion criteria,and the numbers of RVAP group and RVSMP group were compared(187 cases vs.130 cases).There was no difference in the number of final events(new-onset atrial fibrillation after pacemaker implantation):between the two groups(RVAP group vs.RVSMP group: 21 vs.32,p=0.660,p>0.05).The mean follow-up time of both groups was 52.18±2.40 months.There was no difference in the average observation time between the two groups(RVAP group vs.RVSMP group: 51.52±2.6 months vs.52.84±2.3 months,p=0.763,p>0.05).In RVAP group and RVSMP group,the first occurrence time of new atrial fibrillation after pacemaker implantation(18.47±3.5 months vs 24.27±3.5 months,p=0.040,p<0.05)was different.Patients in the right ventricular apex pacing group(RVAP group)had a preoperative LAD of 3.57±0.78 mm and a postoperative LAD of 3.71±0.63 mm.Preoperative LVESD was 3.94±0.30 mm and postoperative LVESD was 4.72±0.30 mm.Preoperative LVEDD was 4.39±1.70 mm,and postoperative LVEDD was 5.22±1.50 mm.Preoperative LVEF was 0.63±0.08,and postoperative LVEF was 0.61±0.07.Patients in the right ventricular median septum pacing group(RVSMP group)had a preoperative LAD of 3.49±0.51 mm and a postoperative LAD of 3.52±0.36 mm.Preoperative LVESD was 3.28±0.37 mm and postoperative LVESD was 3.86±0.22 mm.Preoperative LVEDD was 4.71±0.56 mm,and postoperative LVEDD was 4.80 ± 1.38 mm.Preoperative LVEF was 0.63 ± 0.06,and postoperative LVEF was 0.65±0.03.Compared with RVAP group,the left ventricular diameter of RVSMP group increased significantly(p < 0.05),there were significant differences in the increase of LVEDD and LVESD between the two group(p < 0.05),and LVEF of RVAP group decreased slightly compared with RVSMP group(p > 0.05).There was no difference in other indicators such as LAD,MR,TR,MV E/A and TV E/A(p > 0.05).Hypertension before pacemaker implantation(RR=1.349,95%CI =0.429-1.529,P=0.025),age(RR=1.828,95%CI =1.015-3.292,P=0.045),SSS(RR=2.182,95%CI =1.111-4.284,P=0.023),VVI pacing mode(RR=2.273,95%CI =1.891-9.027,P=0.001),cum%AP(RR=1.028,95%CI =1.012-1.044,P=0.038),left atrial diameter LAD(RR=2.222,95%CI =1.019-4.843,P=0.015)are the risk factors for the occurrence of outcome event.Conclusion Compared with the apex of the right ventricle,pacemaker implantation in the mid-septum of the right ventricle can delay the occurrence of new-onset atrial fibrillation after pacemaker implantation,which has a protective effect on cardiac function.However,the effectiveness of long-term pacemaking in this area needs to be further followed up.Age,hypertension before pacemaker implantation,large preoperative left atrial diameter,sick sinus syndrome,VVI pacing mode and the percentage of cumulative atrial pacing were risk factors for the occurrence of new-onset atrial fibrillation after pacemaker implantation.