A Comparative Study About The Effects Of Left Bundle Branch Pacing And Right Ventricular Septal Pacing On Cardiac Structure And Function In Patients With Ⅲ Degree Atrioventricular Block

Objectives:By comparing two different pacing modes of left bundle branch region pacing(LBBP)and right ventricular septal pacing(RVSP),this study explored the effect of LBBP and RVSP on the cardiac structure and cardiac function in patients with Ⅲ-degree atrioventricular block(AVB)in the short and medium term.Methods:This study is a retrospective study with a sample of hospitalized Patients who were mainly diagnosed with Ⅲ-degree AVB and underwent permanent dual chamber pacemaker implantation in Huaihe Hospital of Henan University from January 2019 to June 2021.Two groups were selected according to the location of implantation of ventricular electrode in patients.Patients with pacing in the left bundle branch region were selected as the LBBP group,while patients with pacing in the right ventricular septum were selected as the RVSP group.According to the inclusion and exclusion criteria of this study,the LBBP group received 25 cases and the RVSP group 30 cases,a total of 55 cases.The data of age,sex of patients in the two groups were collected by medical record retrieval system.QRS duration,plasma N-terminal precursor brain natriuretic peptide(NT-pro BNP)concentration,left ventricular ejection fraction(LVEF),left atrial diameter(LAD),left ventricular end-diastolic diameter(LVEDD)and right ventricular end-diastolic diameter(RVED)of patients were collected before pacemaker implantation,3 months after surgery,6 months after surgery and12 months after surgery.Meanwhile,obtain the pacemaker program control data of patients when 7 days after surgery and 12 months after surgery respectively,and obtain pacing parameters(threshold,sensing,impedance).Finally,statistical differences in the above indicators were compared between patients in the LBBP group and those in the RVSP group.SPSS25.0 statistical software was used for statistical analysis of all samples.Results:1.There were no statistically significant differences in age,gender,preoperative QRS duration,preoperative plasma NT-pro BNP concentration,preoperative LVEF,preoperative LAD,preoperative LVEDD and preoperative RVED between 2 groups(P>0.05).There was no significant difference in pacing parameters(threshold,perception and impedance)7 days after surgery between 2 groups(P>0.05).2.Three months after surgery,QRS duration in LBBP group was lower than that in RVSP group,and the difference was statistically significant(103.36±5.63 vs 130.90±5.97 ms,P<0.001).Three months after surgery,plasma NT-pro BNP concentration,LVEF,LAD,LVEDD and RVED of patients in LBBP group and RVSP group were basically the same,with no statistical significance(P>0.05),suggesting that three months after surgery,LBBP group was better than RVSP group in QRS duration.3.Six months after surgery,QRS duration in LBBP group was lower than that in RVSP group(103.64±6.18 vs 133.33±5.05 ms,P<0.001),LVEF in LBBP group was higher than that in RVSP group(57.48±3.20 vs 55.23±3.33%,P=0.014<0.05),and the differences were statistically significant(P<0.05).Six months after surgery,there were no significant differences in plasma NT-pro BNP concentration,LAD,LVEDD and RVED between LBBP group and RVSP group(P>0.05),suggesting that six months after surgery,LBBP group was superior to RVSP group in QRS duration and LVEF.4.Twelve months after surgery,QRS duration in LBBP group was lower than that in RVSP group(102.80±6.34 vs 135.70±4.57 ms,P<0.001),LVEF in LBBP group was higher than that in RVSP group(57.64±3.16 vs 55.93±2.92%,P=0.043<0.05),and the differences were statistically significant(P<0.05).Twelve months after surgery,there were no significant differences in plasma NT-pro BNP concentration,LAD,LVEDD and RVED between LBBP group and RVSP group(P>0.05).Twelve months after surgery,there was no statistically difference in pacing parameters(threshold,perception and impedance)between LBBP group and RVSP group(P>0.05),suggesting that twelve months after surgery,LBBP group was superior to RVSP group in QRS duration and LVEF.Conclusions:Compared with RVSP,LBBP has a shorter QRS duration of postoperative,suggesting better synchronization of ventricular electrical activity.LBBP pacemaker electrical parameters are stable.LBBP may be more beneficial to protect postoperative cardiac function.In the short and medium term,there were no significant differences in cardiac structure between LBBP group and RVSP group,and long-term effects need to be confirmed by further clinical evidence.