Clinical Application Of New Left Bundle Branch Pacing Technology In Patients With Bradycardia And Heart Failure

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Permanent left bundle branch area pacing improves left ventricular synchrony in atrioventricular block patients:feasibility,safety,and acute effectBackground and Objective Left bundle branch area pacing(LBBAP),as a new pacing approach,still lacks adequate evaluation.The objective of this study is to assess the safety,feasibility and acute effect of LBBAP and to discover its efficacy of improvement of the synchrony of left ventricular in atrioventricular block(AVB)patients.Methods and Results There were 33 AVB patients with indications of ventricular pacing were recruited.Pacing parameters,electrocardiograms,echocardiographic measurements and complications related to LBBAP were evaluated perioperatively and 3-month follow-up.Successful LBBAP was defined as that paced QRS morphology presented with right bundle branch block pattern in precordial lead V1 and the QRS duration(QRSd)was less than 130 ms.LBBAP was succeeded in 90.9%(30/33)of the patients(mean age:55.1±18.5 years old;66.7%male).The mean capture threshold was comparable between that in the procedure(0.76±0.26 V at 0.4 ms)and at 3-month follow-up(0.64±0.20 V at 0.4 ms).The paced QRSd was 112.8±10.9 ms during the procedure and 116.8± 10.4 ms at 3-month follow-up.Baseline left bundle branch or right bundle branch block was corrected(intrinsic QRSd 153.3±27.8 ms vs.paced QRSd 122.2±9.9 ms),and the success rate of bundle branch block correction was 68.7%(11/16).There was one perforation of the ventricular was occurred after the procedure.And the patient was presented with the characteristics of pacing failure,finally,lead revision was successful.Cardiac function and the synchronization of the left ventricular by two-dimensional echocardiographic strain imaging analysis at 3-month follow-up was slightly improved as compared with that at baseline.Conclusion Permanent LBBAP yielded a stable and low pacing threshold,a narrow QRSd and a preserved left ventricular synchrony with rare complications.Our preliminary study indicates that LBBAP might holds promise as one of the most attractive physiological pacing strategies for AVB.FART ? The Improvement of Cardiac Electrical Synchronization and Cardiac Function Delivered by Permanent Left Bundle Branch Area Pacing in Bradycardia Patients with Bundle Branch Block and Preserved Cardiac Function Background and Objective Left bundle branch area pacing(LBBAP)has emerged as anattractive physiological pacing strategy.The correction of left or right bundle branch block(LBBB or RBBB)by LBBAP has been observed,but few data are available.Methods and Results A total of 169 consecutive patients with left ventricular ejection fraction(LVEF)? 40%requiring ventricular pacing and had attempted LBBAP were retrospectively analyzed,including 55 patients with complete LBBB or RBBB.Successful LBBAP was defined as a paced QRS morphology of right bundle branch block pattern in lead V1 and QRS duration(QRSd)less than 130 ms.Implant characteristics,electrocardiograms,pacing parameters,and echocardiographic measurements were evaluated perioperatively and at a 3-month follow-up.When compared with patients without BBB,LBBAP achieved a lower success rate(83.6%vs.93.9%,P=0.033)and required a higher cumulative X-ray dose-area product during the procedure(187.8±142.9 vs.136.3±95.4,pGym2,P=0.010)in patients with BBB.LBBAP was successful in 19 of 26(73.1%)patients with LBBB and in 27 of 29(93.1%)patients with RBBB.If LBBAP succeeded,the correction rate was higher for LBBB than RBBB(100%vs.88.8%).The BBB correction threshold differed from pacing threshold in RBBB(1.74±0.36 vs.0.72±0.26,V@0.4ms),but remained the same in LBBB(0.79±0.17 V at 0.4 ms).Paced QRS duration was significantly narrower in patients with LBBB(169.4±22.6 ms to 121.7±4.1 ms)or RBBB(143.1±16.6 ms to 121.6±5.9 ms)and persisted during 3-month follow-up.Correction of LBBB was associated with improved both left and right ventricular function and synchrony 3 months after implantation,while correction of RBBB resulted in restored right ventricular function.Conclusion Permanent LBBAP yielded efficient correction of wide QRS for both LBBB and RBBB.Corrective LBBAP was associated with improved cardiac function and restoration of synchrony in patients with LBBB or RBBB.Part? Left Bundle Branch Area Pacing Delivered Cardiac Resynchronization Therapy and Comparison with Biventricular Pacing in Patients with Chronic Heart Failure with Left Bundle Branch BlockBackground and Objective This multicenter observational study was aimed to prospectively assessed the efficacy of left bundle branch area pacing(LBBAP)in heart failure patients with LBBB and compare the 6-month outcomes between LBBAP and biventricular pacing(BVP).Methods and Results Consecutive patients with left bundle branch block(LBBB)and left ventricular ejection fraction(LVEF)?35%were recruited if they underwent LBBAP as a primary or rescue strategy from three separate centers from March to December 2018.Patients who received BVP in 2018 were selected by using 2 to 1 propensity score matching to minimize bias.Clinical and implant characteristics,pacing and echocardiographic parameters were assessed during 6-month follow up.LBBAP succeeded in 81.1%patients(30/37),with selective left bundle branch pacing(LBBP)in 33.3%(10/30),paced QRSd?130ms in 25 patients,and combined LBBAP and LV lead pacing for further QRS narrowing in 3 patients.LBBAP resulted in significant QRSd narrowing(from 178.2±18.8ms to 121.8±10.8ms,P<0.001)and improvement in LVEF(from 28.8±4.5%to 44.3±8.7%,P<0.001)during 6-month follow-up.The comparison between 27 patients with LBBAP alone and 54 patients with BVP showed that LBBAP delivered greater reduction in QRSd(58.0ms vs.12.5ms,P<0.001),more increase in LVEF(15.6%vs.7.0%,P<0.001),higher echocardiographic(88.9%vs.66.7%,P=0.035)and clinical response(96.3%vs.75.9%,P=0.028)to cardiac resynchronization therapy(CRT)during 6-month follow up.Conclusions LBBAP could deliver CRT in most patients with heart failure and LBBB,might be a promising resynchronization approach alternative to BVP.