Short-term Efficacy Observation Of Left Bundle Branch Area Pacing

ObjectivesThis study aims to evaluate the short-term safety and effectiveness of LBBAP.Materials and Methods51 patients receiving LBBAP and 51 patients receiving RVP in Fujian Provincial Hospital from Jan 2019 to Oct 2020 were enrolled in this retrospective study.To LBBAP group,the parameters of pacemaker was recorded for 3 times,during the operation,one month later and three months later.Also,we observed the occurrence of new arrhythmias and the changes of cardiac structure in 3-9 months after operation.At the same time,51 patients with right ventricular pacing were enrolled by using the propensity score matching method to observe the QRS duration before and after operation to compare the differences between the two groups.Results1.Among the 51 patients with LBBAP,there were 29 males(56.86%)and 22females(43.14%),aged 61.97±15.60 years old.There were 34 patients(66.67%)implanted pacemakers for III-degree AVB,of whom 6 patients had AF,4 patients(7.84%)for advanced AVB,of whom 1 patient had AF,3 patients(5.88%)for II-degree AVB,3 patients(5.88%)for SSS,3 patients(5.88%)for bradycardic AF and4 patients(7.84%)for AF with a long RR period.In LBBAP group,there were 6patients with left bundle branch block and 4 patients with right bundle branch block before operation.2.Results of parameters: The impedance one month after implantation was obviously less than that in operation.Also,the threshold was slightly declined.The impedance three months after operation was lower than that one month later,but the threshold was the same compared to that one month later.There was no significant difference in the threshold and impedance between the two ventricular leads of 7patients with left bundle branch and right ventricular pacing.2 patients were found frequent pacemaker capsular stimulation after operation.There were no cases of pacemaker wound infection,pocket bleeding,threshold increasing slowly,lead dislocation,fracture or short circuit,etc.3.Results of new arrhythmias: In the LBBAP group,there were 37 patients without atrial fibrillation.We followed up 3-9 months and found that two of these patients were diagnosed atrial fibrillation after implantation.One had subclinical atrial fibrillation and the other had atrial high rate episode which lasted less than 6 min.4.Results of echocardiography: A total of 26 patients with LBBAP performed echocardiography after implantation,of whom 17 patients(65.38%)had moderate mitral regurgitation or worse,11 patients(42.31%)had moderate tricuspid regurgitation or worse,19 patients(73.08%)had enlargement of left atrial dimension,12 patients(46.15%)had enlargement of right atrial dimension,8 patients(30.77%)had enlargement of left ventricular end-diastolic dimension and 7 patients(26.92%)had enlargement of right ventricular dimension.By comparing the echocardiography before and after operation,we found that the postoperative mitral regurgitation was better(P=0.012),and that the left atrium dimension(P=0.001)and right atrium dimension(P=0.022)were smaller than before.Tricuspid regurgitation,left ventricular dimension and right ventricular dimension were the same as those before operation.Among these 26 patients,there were 7 patients had AF before operation while the other 19 not.For the patients without AF,we found that postoperative mitral regurgitation(P=0.006)and tricuspid regurgitation(P=0.020)were better,that left atrium dimension [(3.61±0.45)cm vs(4.06±0.52)cm,P=0.001],right atrium dimension [(3.61±0.45)cm vs(4.06±0.52)cm,P=0.001] and left ventricle dimension(P=0.031)were smaller.Right ventricular dimension were the same as those before operation.The LVEF had an upward trend but no statistics significance.7 patients with atrial fibrillation before implantation performed postoperative echocardiography.Only the left ventricle dimension was slight enlarged than before [(5.65±0.70)cm vs(5.52±0.71)cm,P=0.036).5.Results of QRS duration: The QRS duration after LBBAP was slightly wider than that before surgery [(113.27±14.58)ms vs(106.86±22.88)ms,P<0.001].There was no significant difference in preoperative QRS duration between the LBBAP and the RVP,but the postoperative QRS duration of the LBBAP was significantly shorter than that of the RVP [(113.27±14.58)ms vs(137.45±25.32)ms,P<0.001].ConclusionsLBBAP’s short-term pacemaker parameters were satisfying.The QRS duration after operation was shorter than that of RVP.For non-AF patients,LBBAP may improve valve regurgitation and narrow partial heart cavity.The LVEF had an upward trend but no statistics significance.LBBAP is safety,feasible and worth popularizing.