Study On The Implantation Technology And Electrophysiological Characteristics Of His-Purkinje System Pacin

Objective:His bundle pacing(HBP)is a physiological pacing modality,but with some disadvantages such as difficulty in locating the target area and high radiation exposure.Cardiac electrophysiological three-dimensional mapping system is an effective tool to reduce radiation exposure during cardiac interventional operation and can help realize HBP under low dose fluoroscopic exposure.The purpose of this study was to evaluate the feasibility of a novel cardiac electrophysiological three-dimensional mapping system for guiding HBP.Methods:Twenty patients who had indications for pacemaker implantation were prospectively enrolled and underwent HBP implantation either with the conventional fluoroscopy approach(the standard group)or guided by a novel KODEX-EPD mapping system(the EAM guided group).The implant success rate,procedural details,pacing parameters and procedural related complications were compared between two groups.Results:Twenty consecutive patients were prospectively enrolled and were randomized with 10 patients in each group.HBP was successfully achieved in 9 patients in the standard group and 9 in the EAM guided group.The procedural time was similar between the EAM guided group versus the standard group(86.50±15.05 min vs.85.40± 22.34 min,p=0.90).Compared with the standard group,the EAM guided group had a significant shorter total fluoroscopic time(1.45 ± 0.58 min vs.12.36 ± 5.46 min,p<0.01)and His lead fluoroscopic time(0.84 ± 0.56 min vs.9.27±5.44 min,p<0.01),lower total fluoroscopic dose(3.13 ± 1.24 mGy vs.25.38±11.15 mGy,p<0.01)and His lead fluoroscopic dose(1.85±1.17 mGy vs.19.06 ± 11.03 mGy,p<0.01).No significant differences were observed in paced QRS duration and pacing parameters between two groups.During 3-month follow-up,one patient had a capture threshold increased>1V/1.0ms in the standard group,while no other complications were recorded in either group.Conclusion:The KODEX-EPD mapping system could facilitate HBP implantation with significantly reduced fluoroscopic time and dose without compromising the procedural time.Objective:Left bundle branch pacing(LBBP)is a novel cardiac conduction system pacing modality,which has been rapidly promoted at home and abroad in recent years.However,there are few studies focusing on the implantation technique of LBBP,and the pacing lead deployment remains challenging.This study aimed to evaluate the feasibility of visualization of the tricuspid valve annulus(TVA)to guide lead deployment for LBBP implantation,and to assess LBBP characteristics based on lead tip location.Methods:Successful LBBP with well-defined lead tip location by visualization of the TVA in 20 patients were retrospectively analyzed to develop an image-guided technique to identify the LBBP target site.This technique was then prospectively tested in 60 patients who were randomized into two groups,one using the standard approach(the standard group)and the other using the image-guided technique(the visualization group).The procedural details,electrophysiological characteristics and short-term follow-up were compared between groups.Results:LBBP was attempted in 30 patients in each group,and were successfully achieved in 28 patients in the standard group and in 29 in the visualization group.The procedural(66.76±14.62 min vs.85.46 ± 20.19 min,p<0.01)and fluoroscopic durations(7.83±2.05 min vs.11.11±3.51 min,p<0.01)in the visualization group were significantly shorter than those in the standard group.Compared with the standard group,the number of lead deployment attempts in the visualization group was fewer(2.03 ±1.18 vs.2.96 ± 1.17,p<0.01),and the proportion of recording left bundle branch potential was higher(79.3%vs.46.4%,p=0.01).Conclusion:Using a visualization technique,the procedural and fluoroscopic durations for LBBP implantation were significantly shortened with fewer lead repositioning attempts,which is expected to be a novel implantation technique for LBBP.Objective:His-Purkinje System Pacing(HPSP)can activate its own cardiac conduction system and produce rapid ventricular activation,which is considered as a physiological pacing modality.However,there are few studies on pacing characteristics of different HPSP.The purpose of this study was to evaluate the pacing characteristics of different HPSP,thus to guide the therapeutic selection of HPSP.Methods:Patients who successfully underwent His bundle pacing(HBP)or left bundle branch pacing(LBBP)with bradycardia indications from April 2018 to August 2019 were retrospectively enrolled.Patients implanted with successful HBP were further divided into atrial His bundle pacing(AHBP)or ventricular His bundle pacing(VHBP)according to the lead location confirmed by intraoperative visualization of the tricuspid value annulus or postoperative echocardiography.The electrophysiological characteristics and pacing parameters were compared among these three groups.Results:A total of 135 patients were retrospectively analyzed.Among them.30 patients were assigned to AHBP group,52 were assigned to VHBP group,and 53 were assigned to LBBP group.The LBBP group had significantly shorter procedural(62.28± 13.27min)and fluoroscopic durations(7.70±2.66min)than the AHBP(procedural duration:82.50±19.75min,P<0.05 compared with LBBP;fluoroscopic duration:11.83±3.91min.P<0.05 compared with LBBP)and VHBP groups(procedural duration:79.13±19.25min,P<0.05 compared with LBBP;fluoroscopic duration:12.38±4.36min,P<0.05 compared with LBBP).The proportion of non-selective pacing was significantly lower in the AHBP group(30.0%)than those in the VHBP(75.0%)and LBBP groups(90.6%).In terms of intraoperative pacing parameters,the capture threshold was significantly higher(1.07±0.26V/1.0ms vs.0.89±0.22V/1.0ms vs.0.77±0.18V/0.4ms,P<0.01 respectively),and the R-wave amplitude was significantly lower(3.71 ±1.72mV vs.5.81 ±2.37mV vs.10.27±4.71mV,P<0.05 respectively)in the AHBP group than those in the VHBP and LBBP groups at implantation and during 3-month follow-up.No significant differences were observed in procedure related complications among three groups during 3-month follow-up.Conclusion:VHBP and LBBP had better pacing performances than AHBP and might be more ideal pacing modalities for bradycardia patients.Objective:Left bundle branch pacing(LBBP)is a rapidly growing conduction system pacing technique in recent years.Anatomically,left bundle branch is widely distributed.However,little is known regarding the electrophysiological and anatomic characteristics of different types of LBBP.This study aimed to evaluate the electrophysiological characteristics and the anatomic distribution of pacing different branches in LBBP,so as to guide the selection of treatment strategies for LBBP.Methods:Consecutive bradycardia patients with successful LBBP were enrolled and were classified into groups according to the paced electrocardiogram and the lead location confirmed by visualization of the tricuspid valve annulus(TVA).Electrocardiogram,vectorcardiogram,pacing properties,and lead tip location were analyzed among groups.Results:Ninety-one patients were enrolled.According to the paced electrocardiogram,48 patients were classified into the left bundle trunk pacing(LBTP)group,and 43 patients were the left bundle fascicular pacing(LBFP)group.The paced QRS duration in the LBTP group was significantly shorter than that in the LBFP group(108.1±9.9 ms vs.112.9 ± 11.2 ms,p=0.03),with a more rightward QRS transition zone(p=0.01).The paced QRS area in the LBTP group was similar to that during intrinsic rhythm(35.1 ±15.8 μVs vs.34.7±16.6 μVs,p=0.98),whereas in the LBFP group,the paced QRS area was significantly larger compared to intrinsic rhythm(43.4 ± 15.8 μVs vs.35.7±18.0μVs,p=0.01).The lead tip sites for LBTP were located in a small fan-shaped area with the TVA summit as the origin,whereas fascicular pacing sites were more likely in a larger and more distal fan-shaped area.Conclusion:Pacing the proximal left bundle main trunk produced better electrical synchrony than pacing the distal left bundle fascicles.A technique of visualization of the TVA can facilitate to achieve LBTP.