Clinical Efficacy And Safety Of Left Bundle Branch Area Pacing

BACKGROUND With the aging of the population,the number of patients with symptomatic bradycardia is increasing year by year.The occurrence of this symptom is due to the damage to the integrity of the cardiac conduction system,which results in a variety of pathophysiological mechanisms.It is a potential,irreversible and life-threatening disease.Pacemaker implantation is an effective means to treat this kind of disease,which makes the demand for pacemaker implantation continues to increase.Traditional right ventricular apical pacing（RVAP）can induce atrial fibrillation and heart failure.The clinical prognosis of right ventricular septal pacing（RVSP）is controversial.Left bundle branch area pacing（LBBa P）is more physiological than the above two pacing methods.However,at present,the clinical application and efficacy of this technique is not long,and the sample size is small,so more clinical studies are needed to explore its effectiveness and safety.The purpose of this study was to observe the clinical efficacy and safety of left bundle branch pacing.METHODS A total of 111 patients requiring pacing therapy due to bradycardia were selected and divided into RVAP group,RVSP group,and LBBa P group according to the site of ventricular pacing electrode implantation.The clinical data of the three groups were comparable,and pacing electrodes were implanted at different sites.Pacing parameters（threshold,R-Wave amplitude and impedance）were measured in the three groups during surgery and at 7d and 12 months after surgery.Echocardiography was performed before surgery,7d after surgery,and 12 months after surgery to measure left ventricular end-diastolic diameter（LVDd）,left ventricular end-systolic diameter（LVDs）,and left ventricular ejection fraction（LVEF）in the three groups of patients with and without heart failure.The plasma N-terminal pro-B-type natriuretic peptide（NT-Pro BNP）was detected by electrochemiluminescence.Twelve electrocardiograms were performed before surgery,7d after surgery,and 12 months after surgery to record QRS duration.Pacing-related complications,rehospitalization for heart failure and cardiac death were statistically analyzed among the three groups.The operation time,X-ray exposure time,and ray dose of patients in the LBBa P,RVAP,and RVSP groups were counted.RESULTS There was no significant difference in pacing parameters at different times among the three groups（P > 0.05）.Compared with before operation,plasma NT-Pro BNP levels decreased in the three groups of patients with heart failure at 7d after operation（P < 0.05）,and there was no significant difference in LVEF,LVDs,and LVDd（P > 0.05）.At 12 months after operation,LVEF decreased,LVDs,LVDd and plasma NT-Pro BNP levels increased in patients with heart failure in RVAP group（plasma NT-Pro BNP level P < 0.05）;the above indicators did not change significantly in patients with heart failure in RVSP group（P > 0.05）;LVEF increased,LVDs,LVDd and plasma NT-Pro BNP levels decreased in patients with heart failure in LBBa P group（P < 0.05）.There was no significant difference in the above cardiac function indicators at each time point among the three groups of non-heart failure patients（P > 0.05）.Compared with before operation,QRS duration was prolonged in the three groups（P < 0.05）,and there was significant difference between LBBa P group < RVSP group < RVAP group（P <0.05）.The rehospitalization rate due to heart failure was lower in the LBBa P group than in the RVAP group（P < 0.05）.The operation time,radiation exposure time and radiation dose in the LBBa P group were greater than those in the other two groups（P < 0.05）.CONCLUSION LBBa P pacing parameters are stable and have no significant effect on cardiac function,but has little effect on the duration of QRS wave,which is especially suitable for patients with heart failure to reduce the rehospitalization rate of heart failure,but the operation duration and X-ray exposure of LBBa P is longer than another two groups,and the radiation dose of LBBa P is higher than another two groups.