Effects Of Left Bundle Branch Pacing And Right Ventricular Septal Pacing On Cardiac Structure And Function

Objective:Left bundle branch pacing(LBBP)and right ventricular septal pacing(RVSP)are commonly used in clinic,this study compared the short-term effects of two pacing sites on cardiac structure and function.Methods:51 patients who were diagnosed as third degree atrioventricular(AV)block and treated with permanent pacemaker implantation at the department of Cardiovascular disease,the Second Hospital of Hebei Medical University from October 2018 to September 2019.LBBP were performed in group of 24 patients,another 27 patients received RVSP.According to the inclusion and exclusion criteria of this study,a total of 42 patients were included in the final analysis,there were 21 cases in LBBP group and 21 cases in RVSP group.All patients were followed at our clinic at the first week,the first month,and the sixth month after the implantation.During the follow up the pacing parameters of two groups were observed and the width of QRS wave was used as the index of ventricular electrical activity.At the meantime,Six-minute walking test(6-MWT),B-type natriuretic peptide(BNP)and echocardiography were used six months after operation to evaluate the changes of cardiac function.Compare the above indexes of the two groups.SPSS 22.0 software was used for statistical analysis.Results:1.General data was compared before operation:The sex,age and based disease have no difference between the two groups(P>0.05).2.There were no significant differences in pacing threshold,pacing perception and impedance between the two groups(P>0.05).3.There were no significant differences in preoperative 6-MWT and BNP between the two groups(P>0.05).At 6 months after operation,BNP value in LBBP group was statistically lower than those in RVSP group(85.20±19.76 vs 100.02±21.89pg/ml,P=0.027),but the value of 6-MWT was no significant difference between two groups(446.38±36.40 vs 430.24±37.21 m,P=0.163);.4.There were no significant differences in the QRS wave duration between two groups before the operation(112.05±20.47 vs 113.87±19.22 ms,P=0.726).There was no significant difference in the duration of pacing QRS wave in LBBP group after 6 months follow-up(115.10±14.97 vs 112.05±20.47 ms,P=0.240),and the paced QRS wave duration in RVSP group was wider than that in LBBP group(131.46±9.26 vs 115.10±14.97 ms,P=0.001).5.At 6 months after operation,the left ventricular systolic and diastolic function and right ventricular systolic function in LBBP group were better than RVSP group,LVEF(59.52±7.58 vs 55.30±5.83%,P=0.002)and TAPSE(20.28±4.69 vs 18.59±4.22 mm,P=0.001)in LBBP group were statistically higher than those in RVSP group,the LAVI(31.94±3.57 vs 34.02±3.55ml/m~2,P=0.000)andE/Ea(8.37±3.60 vs 10.09±3.94ml/m~2,P=0.000)in LBBP group were statistically lower than those in RVSP group,but LAD,LVEDD,TRPV,E/A and Ea were no significant differences between the two groups(P>0.05).6.At 6 months after operation,LBBP group had better left ventricular myocardial strain and strain rate than RVSP group.The GS(-16.29±4.34 vs-14.46±3.08,P=0.001),SRs(-1.11±0.24 vs-0.85±0.29,P=0.002),SRe(1.24±0.49 vs 1.03±0.40,P=0.001)and SRa(1.32±0.38 vs 1.06±0.47,P=0.000)were higher in RVSP group.7.At 6 months after operation,the left and right ventricular systolic synchronism were better in LBBP group than RVSP group.The IVMD(33.05±15.59 vs 42.11±13.86 ms,P=0.000),SPWMD(105.95±48.77 vs 133.92±50.67,P=0.000),Ts-SD(30.27±10.66 vs 33.30±8.56,P=0.003)and Ts-maxD(95.95±40.27 vs 120.43±45.37,P=0.000)in LBBP group were statistically lower than those in RVSP group.Conclusion:Compared with RVSP,LBBP could achieve favorable cardiac electrical and mechanical synchrony,which is more beneficial to protect the structure and function of the cardiac,and is a physiological pacing mode.