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Impact of Left Bundle Branch Area Pacing vs. Right Ventricular Pacing in Atrioventricular Block (LEAP-Block) (LEAP-Block)

Primary Purpose

Atrioventricular Block, Left Bundle Branch Area Pacing, Right Ventricular Pacing

Status
Recruiting
Phase
Not Applicable
Locations
China
Study Type
Interventional
Intervention
Left bundle branch area pacing
Right ventricular pacing
Sponsored by
Fu Wai Hospital, Beijing, China
About
Eligibility
Locations
Arms
Outcomes
Full info

About this trial

This is an interventional treatment trial for Atrioventricular Block focused on measuring Atrioventricular Block, Left bundle branch area pacing, Right ventricular pacing

Eligibility Criteria

18 Years - 90 Years (Adult, Older Adult)All SexesDoes not accept healthy volunteers

Inclusion Criteria:

  • a. Adult patients aged 18-90;
  • b. AV block patients with ventricular pacing indications and the expected rate of ventricular pacing(VP)> 40%, including (a)Third-degree AV block; (b) Second degree AV block (type II); (c) intermittent advanced AV block with expected VP>40%; (d)Symptomatic first degree AV block and PR interval on ECG ≥ 250ms;
  • c. The subject is able to receive a pectoral implant;
  • d. The subject is willing and able to comply with the protocol;
  • e. The subject is expected to remain available for follow-up visits at the study centers.
  • f. Subject or authorized legal guardian or representative has signed and dated the study Subject Informed Consent

Exclusion Criteria:

  • a. Baseline echocardiographic assessment of patients with impaired LV function (LVEF<50%);
  • b. Having difficulties in follow-up: Those who cannot accept 2-year follow-up on time due to physical condition or other reasons;
  • c. Patients with persistent atrial fibrillation;
  • d. Pacemaker replacement without new implanted ventricular electrodes;
  • e. Patients with implantable cardioverter-defibrillator (ICD) indications;
  • f. Surgery is required within 1 year due to severe structural heart disease;
  • g. Patients with tricuspid mechanical valve replacement, or congenital heart disease (including transposition of the great arteries, or permanent left superior vena cava, etc), or AV block resulting from: (a) Hypertrophic cardiomyopathy(HCM)vpost (modified) Morrow surgery, (b) ventricular septal defect repair; and those who are unlikely to achieve successful LBBAP procedure.

Sites / Locations

  • Beijing Anzhen hospital, Capital Medical University
  • Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical SciencesRecruiting
  • Peking Union Medical College Hospital
  • The Second Hospital of Hebei Medical University
  • Fuwai Central China Cardiovascular Hospital
  • The First Affiliated Hospital of Zhengzhou University
  • Tianjin Medical University General Hospital
  • Teda International Cardiovascular Hospital

Arms of the Study

Arm 1

Arm 2

Arm Type

Experimental

Active Comparator

Arm Label

LBBAP group

RVP group

Arm Description

AV block patients randomized to left bundle branch area pacing

AV block patients randomized to right ventricular pacing group

Outcomes

Primary Outcome Measures

The primary endpoint is the time to a first event of composite outcomes, including all-cause death, hospitalization for heart failure, and an upgrade to cardiac resynchronization therapy due to pacing induced heart failure.
All-cause death: including cardiovascular and non-cardiovascular deaths. Hospitalization for heart failure: an unplanned outpatient or emergency department visit or inpatient hospitalization in which the patient presented with signs and symptoms consistent with heart failure and required medication therapy. Upgrade to cardiac resynchronization therapy (CRT): Upgrade from dual-chamber pacemaker to CRT-Pacemaker/CRT-Defibrillator due to impaired LV function (LVEF decrease to 40% or less).

Secondary Outcome Measures

Rate of the composite outcomes of all-cause death and/or hospitalization for heart failure
All-cause death: including cardiovascular and non-cardiovascular deaths. Hospitalization for heart failure: an unplanned outpatient or emergency department visit or inpatient hospitalization in which the patient presented with signs and symptoms consistent with heart failure and required medication therapy.
Rate of the composite outcomes of hospitalization for heart failure and/or an upgrade to cardiac resynchronization therapy due to pacing induced heart failure.
Hospitalization for heart failure: an unplanned outpatient or emergency department visit or inpatient hospitalization in which the patient presented with signs and symptoms consistent with heart failure and required medication therapy. Upgrade to cardiac resynchronization therapy: Upgrade from dual chamber pacemaker to CRT-P/CRT-D due to impaired LV function (LVEF decrease to 40% or less).
Rate of the composite outcomes of LVEF <50%, and/or an increase in LVESV ≥15% during follow-up as compared with the value at randomization
Echocardiography will be assessed every 6 month during follow-up to determine whether the LVEF is less than 50% and/or the LVESV is increased by 15% or more.
The value of LVEF and LVESV assessed by echocardiography at 1-year and 2-year follow-up
Echocardiography will be assessed at 1-year, and 2-year follow-up and the absolute value of LVEF and LVESV will be compared between two groups.
The time to a first event of LVEF <50% and decrease in LVEF by ≥ 10% during 2 years follow-up as compared with the value at randomization.
Echocardiography will be assessed every 6 month during follow-up to determine whether the LVEF is less than 50% and decreased by 15% or more as compared with the value at randomization.
The immediate success rate of the LBBAP procedure
Successful LBBAP procedure is identified according to ECG and intracardiac electrogram (IEGM) during the procedure. All LBBAP procedures will be categorized as selective left bundle branch pacing (S-LBBP), non-selective left bundle branch pacing(NS-LBBP), or left ventricular septal pacing (LVSP).
The rate of procedure and Device related complications
Procedure complications include pneumothorax, hemothorax, and air embolism. Device related complications include lead and pocket complications.
Changes in Pacing parameters and ECG characteristics.
Pacing parameters include pacing thresholds (ventricle), Sense ampitude (ventricle), Impedance (ventricle). ECG characteristics include paced QRS duration and QRS morphology, etc.
The occurrence of LV dyssynchrony
The occurrence of LV dyssynchrony will be evaluated by echocardiography during 2-year follow-up.
Atrial high-rate episodes recorded by the pacemaker
Atrial high-rate episodes recorded in the pacemaker will be followed during two years of follow-up
The long-term success rate of LBBAP
In LBBAP group, the successful LBBAP will be identified according ECG features at 2-years follow-up

Full Information

First Posted
January 26, 2021
Last Updated
July 9, 2022
Sponsor
Fu Wai Hospital, Beijing, China
Collaborators
Beijing Anzhen Hospital, The First Affiliated Hospital of Zhengzhou University, The Second Hospital of Hebei Medical University, Fuwai Central China Cardiovascular Hospital, Tianjin Medical University General Hospital, Teda International Cardiovascular Hospital, Tianjin, China, Peking Union Medical College Hospital, Chinese Society of Cardiology
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1. Study Identification

Unique Protocol Identification Number
NCT04730921
Brief Title
Impact of Left Bundle Branch Area Pacing vs. Right Ventricular Pacing in Atrioventricular Block (LEAP-Block)
Acronym
LEAP-Block
Official Title
Impact of Left Bundle Branch Area Pacing vs. Right Ventricular Pacing in Atrioventricular Block (LEAP-Block): A Randomized Controlled Trial
Study Type
Interventional

2. Study Status

Record Verification Date
July 2022
Overall Recruitment Status
Recruiting
Study Start Date
November 13, 2020 (Actual)
Primary Completion Date
June 30, 2024 (Anticipated)
Study Completion Date
December 31, 2025 (Anticipated)

3. Sponsor/Collaborators

Responsible Party, by Official Title
Principal Investigator
Name of the Sponsor
Fu Wai Hospital, Beijing, China
Collaborators
Beijing Anzhen Hospital, The First Affiliated Hospital of Zhengzhou University, The Second Hospital of Hebei Medical University, Fuwai Central China Cardiovascular Hospital, Tianjin Medical University General Hospital, Teda International Cardiovascular Hospital, Tianjin, China, Peking Union Medical College Hospital, Chinese Society of Cardiology

4. Oversight

Studies a U.S. FDA-regulated Drug Product
No
Studies a U.S. FDA-regulated Device Product
Yes
Product Manufactured in and Exported from the U.S.
Yes
Data Monitoring Committee
Yes

5. Study Description

Brief Summary
This is a multicenter, randomized controlled study. The aim of this study is to compare the impact of LBBAP on left ventricular function as compared with traditional right ventricular pacing in patients with atrioventricular block.
Detailed Description
LEAP-BLOCK is a prospective, multi-center, randomized controlled trial that is designed to determine whether left bundle branch area pacing (LBBAP) may reduce the risk of RV ventricular pacing induced cardiac dysfunction as compared with traditional RV pacing (RVP) in patients with atrioventricular (AV) block and normal LV function (LVEF≥50%) who require high percent of ventricular pacing. The primary aim of this trial is to compare the time to first event (composite of all-cause mortality and newly heart failure hospitalization and device upgrade due to heart failure) between LBBAP and RVP group in patients with AV block. Patients with AV block and normal LV function who require high burden of ventricular pacing (expected >40%) will be randomized to LBBAP or RVP group for therapy. Patients will be followed at least every 3 months for clinical status and every 6 months for echocardiographic evaluation until the study closure.

6. Conditions and Keywords

Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
Atrioventricular Block, Left Bundle Branch Area Pacing, Right Ventricular Pacing, Heart Failure
Keywords
Atrioventricular Block, Left bundle branch area pacing, Right ventricular pacing

7. Study Design

Primary Purpose
Treatment
Study Phase
Not Applicable
Interventional Study Model
Parallel Assignment
Masking
ParticipantOutcomes Assessor
Allocation
Randomized
Enrollment
458 (Anticipated)

8. Arms, Groups, and Interventions

Arm Title
LBBAP group
Arm Type
Experimental
Arm Description
AV block patients randomized to left bundle branch area pacing
Arm Title
RVP group
Arm Type
Active Comparator
Arm Description
AV block patients randomized to right ventricular pacing group
Intervention Type
Device
Intervention Name(s)
Left bundle branch area pacing
Intervention Description
Left bundle branch area pacing(LBBAP) is a novel physiological pacing form for ventricular pacing. In patients received LBBAP, the pacing lead will be placed at left bundle branch area to achieve narrow paced QRS duration.
Intervention Type
Device
Intervention Name(s)
Right ventricular pacing
Intervention Description
Right ventricular pacing is the traditional pacing modality for ventricular pacing. The pacing lead was placed in the apex or septum of right ventricle.
Primary Outcome Measure Information:
Title
The primary endpoint is the time to a first event of composite outcomes, including all-cause death, hospitalization for heart failure, and an upgrade to cardiac resynchronization therapy due to pacing induced heart failure.
Description
All-cause death: including cardiovascular and non-cardiovascular deaths. Hospitalization for heart failure: an unplanned outpatient or emergency department visit or inpatient hospitalization in which the patient presented with signs and symptoms consistent with heart failure and required medication therapy. Upgrade to cardiac resynchronization therapy (CRT): Upgrade from dual-chamber pacemaker to CRT-Pacemaker/CRT-Defibrillator due to impaired LV function (LVEF decrease to 40% or less).
Time Frame
Within two years after device implantation
Secondary Outcome Measure Information:
Title
Rate of the composite outcomes of all-cause death and/or hospitalization for heart failure
Description
All-cause death: including cardiovascular and non-cardiovascular deaths. Hospitalization for heart failure: an unplanned outpatient or emergency department visit or inpatient hospitalization in which the patient presented with signs and symptoms consistent with heart failure and required medication therapy.
Time Frame
Within 2 years after device implantation
Title
Rate of the composite outcomes of hospitalization for heart failure and/or an upgrade to cardiac resynchronization therapy due to pacing induced heart failure.
Description
Hospitalization for heart failure: an unplanned outpatient or emergency department visit or inpatient hospitalization in which the patient presented with signs and symptoms consistent with heart failure and required medication therapy. Upgrade to cardiac resynchronization therapy: Upgrade from dual chamber pacemaker to CRT-P/CRT-D due to impaired LV function (LVEF decrease to 40% or less).
Time Frame
Within 2 years after device implantation
Title
Rate of the composite outcomes of LVEF <50%, and/or an increase in LVESV ≥15% during follow-up as compared with the value at randomization
Description
Echocardiography will be assessed every 6 month during follow-up to determine whether the LVEF is less than 50% and/or the LVESV is increased by 15% or more.
Time Frame
Within 2 years after device implantation
Title
The value of LVEF and LVESV assessed by echocardiography at 1-year and 2-year follow-up
Description
Echocardiography will be assessed at 1-year, and 2-year follow-up and the absolute value of LVEF and LVESV will be compared between two groups.
Time Frame
24 months
Title
The time to a first event of LVEF <50% and decrease in LVEF by ≥ 10% during 2 years follow-up as compared with the value at randomization.
Description
Echocardiography will be assessed every 6 month during follow-up to determine whether the LVEF is less than 50% and decreased by 15% or more as compared with the value at randomization.
Time Frame
24 months
Title
The immediate success rate of the LBBAP procedure
Description
Successful LBBAP procedure is identified according to ECG and intracardiac electrogram (IEGM) during the procedure. All LBBAP procedures will be categorized as selective left bundle branch pacing (S-LBBP), non-selective left bundle branch pacing(NS-LBBP), or left ventricular septal pacing (LVSP).
Time Frame
1 weeks
Title
The rate of procedure and Device related complications
Description
Procedure complications include pneumothorax, hemothorax, and air embolism. Device related complications include lead and pocket complications.
Time Frame
24 months
Title
Changes in Pacing parameters and ECG characteristics.
Description
Pacing parameters include pacing thresholds (ventricle), Sense ampitude (ventricle), Impedance (ventricle). ECG characteristics include paced QRS duration and QRS morphology, etc.
Time Frame
24 months
Title
The occurrence of LV dyssynchrony
Description
The occurrence of LV dyssynchrony will be evaluated by echocardiography during 2-year follow-up.
Time Frame
24 months
Title
Atrial high-rate episodes recorded by the pacemaker
Description
Atrial high-rate episodes recorded in the pacemaker will be followed during two years of follow-up
Time Frame
24 months
Title
The long-term success rate of LBBAP
Description
In LBBAP group, the successful LBBAP will be identified according ECG features at 2-years follow-up
Time Frame
24 months
Other Pre-specified Outcome Measures:
Title
Pre-existing heart disease based primary outcome
Description
All-cause death and/or hospitalization for heart failure comparison based on pre-exsiting heart disease (e.g. coronary heart disease, atrial fibirllation, valvular heart disease, and dilated cardiomyopathy.
Time Frame
Within 2 years after device implantation
Title
Baseline QRSd based primary outcome
Description
All-cause death and/or hospitalization for heart failure comparison based on baseline QRSd (>120ms vs. ≤120ms)
Time Frame
Within 2 years after device implantation

10. Eligibility

Sex
All
Minimum Age & Unit of Time
18 Years
Maximum Age & Unit of Time
90 Years
Accepts Healthy Volunteers
No
Eligibility Criteria
Inclusion Criteria: a. Adult patients aged 18-90; b. AV block patients with ventricular pacing indications and the expected rate of ventricular pacing(VP)> 40%, including (a)Third-degree AV block; (b) Second degree AV block (type II); (c) intermittent advanced AV block with expected VP>40%; (d)Symptomatic first degree AV block and PR interval on ECG ≥ 250ms; c. The subject is able to receive a pectoral implant; d. The subject is willing and able to comply with the protocol; e. The subject is expected to remain available for follow-up visits at the study centers. f. Subject or authorized legal guardian or representative has signed and dated the study Subject Informed Consent Exclusion Criteria: a. Baseline echocardiographic assessment of patients with impaired LV function (LVEF<50%); b. Having difficulties in follow-up: Those who cannot accept 2-year follow-up on time due to physical condition or other reasons; c. Patients with persistent atrial fibrillation; d. Pacemaker replacement without new implanted ventricular electrodes; e. Patients with implantable cardioverter-defibrillator (ICD) indications; f. Surgery is required within 1 year due to severe structural heart disease; g. Patients with tricuspid mechanical valve replacement, or congenital heart disease (including transposition of the great arteries, or permanent left superior vena cava, etc), or AV block resulting from: (a) Hypertrophic cardiomyopathy(HCM)vpost (modified) Morrow surgery, (b) ventricular septal defect repair; and those who are unlikely to achieve successful LBBAP procedure.
Central Contact Person:
First Name & Middle Initial & Last Name or Official Title & Degree
Xiaofei Li, M.D.
Phone
+8617801013995
Email
lixiaofei0103@163.com
First Name & Middle Initial & Last Name or Official Title & Degree
Zhao Wang, M.D.
Phone
+8618010421619
Email
dream_wangzhao@163.com
Overall Study Officials:
First Name & Middle Initial & Last Name & Degree
Xiaohan Fan, PhD.
Organizational Affiliation
Fuwai Hospital
Official's Role
Study Chair
Facility Information:
Facility Name
Beijing Anzhen hospital, Capital Medical University
City
Beijing
State/Province
Beijing
ZIP/Postal Code
100029
Country
China
Individual Site Status
Not yet recruiting
Facility Contact:
First Name & Middle Initial & Last Name & Degree
Yongquan Wu, M.D.
Phone
+8613810751596
Email
wuyongquan67@163.com
First Name & Middle Initial & Last Name & Degree
Yongquan Wu, M.D.
Facility Name
Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences
City
Beijing
State/Province
Beijing
ZIP/Postal Code
100037
Country
China
Individual Site Status
Recruiting
Facility Contact:
First Name & Middle Initial & Last Name & Degree
Zhao Wang, M.D.
Phone
01088322405
Email
dream_wangzhao@163.com
First Name & Middle Initial & Last Name & Degree
Xiaohan Fan, Ph.D.
Phone
01088322402
Email
fanxiaohan@fuwaihospital.org
First Name & Middle Initial & Last Name & Degree
Xiaofei Li, M.D.
First Name & Middle Initial & Last Name & Degree
Xiaohan Fan, Ph.D.
Facility Name
Peking Union Medical College Hospital
City
Beijing
State/Province
Beijing
ZIP/Postal Code
100730
Country
China
Individual Site Status
Not yet recruiting
Facility Contact:
First Name & Middle Initial & Last Name & Degree
Taibo Chen, M.D.
First Name & Middle Initial & Last Name & Degree
Taibo Chen, M.D.
Facility Name
The Second Hospital of Hebei Medical University
City
Shijiazhuang
State/Province
Hebei
Country
China
Individual Site Status
Not yet recruiting
Facility Contact:
First Name & Middle Initial & Last Name & Degree
Ruiqin Xie, M.D.
Email
ruiqin_xie@sina.com
First Name & Middle Initial & Last Name & Degree
Ruiqin Xie, M.D.
Facility Name
Fuwai Central China Cardiovascular Hospital
City
Zhengzhou
State/Province
Henan
ZIP/Postal Code
450003
Country
China
Individual Site Status
Not yet recruiting
Facility Contact:
First Name & Middle Initial & Last Name & Degree
Haitao Yang, M.D.
Email
leoparddoctor1@163.com
First Name & Middle Initial & Last Name & Degree
Haitao Yang, M.D.
Facility Name
The First Affiliated Hospital of Zhengzhou University
City
Zhengzhou
State/Province
Henan
ZIP/Postal Code
450052
Country
China
Individual Site Status
Not yet recruiting
Facility Contact:
First Name & Middle Initial & Last Name & Degree
Chunguang Qiu, M.D.
Phone
+860371-66913114
Email
qcg123@163.com
First Name & Middle Initial & Last Name & Degree
Chunguang Qiu, M.D.
Facility Name
Tianjin Medical University General Hospital
City
Tianjin
State/Province
Tianjin
ZIP/Postal Code
300052
Country
China
Individual Site Status
Not yet recruiting
Facility Contact:
First Name & Middle Initial & Last Name & Degree
Wenjuan Zhang, M.D.
First Name & Middle Initial & Last Name & Degree
Wenjuan Zhang, M.D.
Facility Name
Teda International Cardiovascular Hospital
City
Tianjin
State/Province
Tianjin
Country
China
Individual Site Status
Not yet recruiting
Facility Contact:
First Name & Middle Initial & Last Name & Degree
Wenhua Lin, M.D.
First Name & Middle Initial & Last Name & Degree
Wenhua Lin, M.D.

12. IPD Sharing Statement

Plan to Share IPD
No
Citations:
PubMed Identifier
19915220
Citation
Yu CM, Chan JY, Zhang Q, Omar R, Yip GW, Hussin A, Fang F, Lam KH, Chan HC, Fung JW. Biventricular pacing in patients with bradycardia and normal ejection fraction. N Engl J Med. 2009 Nov 26;361(22):2123-34. doi: 10.1056/NEJMoa0907555. Epub 2009 Nov 15.
Results Reference
background
PubMed Identifier
29274474
Citation
Vijayaraman P, Naperkowski A, Subzposh FA, Abdelrahman M, Sharma PS, Oren JW, Dandamudi G, Ellenbogen KA. Permanent His-bundle pacing: Long-term lead performance and clinical outcomes. Heart Rhythm. 2018 May;15(5):696-702. doi: 10.1016/j.hrthm.2017.12.022. Epub 2017 Dec 20.
Results Reference
background
PubMed Identifier
30734436
Citation
Cho SW, Gwag HB, Hwang JK, Chun KJ, Park KM, On YK, Kim JS, Park SJ. Clinical features, predictors, and long-term prognosis of pacing-induced cardiomyopathy. Eur J Heart Fail. 2019 May;21(5):643-651. doi: 10.1002/ejhf.1427. Epub 2019 Feb 8.
Results Reference
background
PubMed Identifier
31504437
Citation
Tayal B, Fruelund P, Sogaard P, Riahi S, Polcwiartek C, Atwater BD, Gislason G, Risum N, Torp-Pedersen C, Kober L, Kragholm KH. Incidence of heart failure after pacemaker implantation: a nationwide Danish Registry-based follow-up study. Eur Heart J. 2019 Nov 21;40(44):3641-3648. doi: 10.1093/eurheartj/ehz584.
Results Reference
background
PubMed Identifier
30093543
Citation
Huang W, Su L, Wu S, Xu L, Xiao F, Zhou X, Mao G, Vijayaraman P, Ellenbogen KA. Long-term outcomes of His bundle pacing in patients with heart failure with left bundle branch block. Heart. 2019 Jan;105(2):137-143. doi: 10.1136/heartjnl-2018-313415. Epub 2018 Aug 9.
Results Reference
background
PubMed Identifier
29535066
Citation
Abdelrahman M, Subzposh FA, Beer D, Durr B, Naperkowski A, Sun H, Oren JW, Dandamudi G, Vijayaraman P. Clinical Outcomes of His Bundle Pacing Compared to Right Ventricular Pacing. J Am Coll Cardiol. 2018 May 22;71(20):2319-2330. doi: 10.1016/j.jacc.2018.02.048. Epub 2018 Mar 10.
Results Reference
background
PubMed Identifier
27457727
Citation
Vijayaraman P, Dandamudi G. Anatomical approach to permanent His bundle pacing: Optimizing His bundle capture. J Electrocardiol. 2016 Sep-Oct;49(5):649-57. doi: 10.1016/j.jelectrocard.2016.07.003. Epub 2016 Jul 11.
Results Reference
background
PubMed Identifier
31048065
Citation
Li X, Li H, Ma W, Ning X, Liang E, Pang K, Yao Y, Hua W, Zhang S, Fan X. Permanent left bundle branch area pacing for atrioventricular block: Feasibility, safety, and acute effect. Heart Rhythm. 2019 Dec;16(12):1766-1773. doi: 10.1016/j.hrthm.2019.04.043. Epub 2019 Apr 29.
Results Reference
background
PubMed Identifier
32400967
Citation
Li X, Qiu C, Xie R, Ma W, Wang Z, Li H, Wang H, Hua W, Zhang S, Yao Y, Fan X. Left bundle branch area pacing delivery of cardiac resynchronization therapy and comparison with biventricular pacing. ESC Heart Fail. 2020 Aug;7(4):1711-1722. doi: 10.1002/ehf2.12731. Epub 2020 May 13.
Results Reference
background
PubMed Identifier
25446158
Citation
Sharma PS, Dandamudi G, Naperkowski A, Oren JW, Storm RH, Ellenbogen KA, Vijayaraman P. Permanent His-bundle pacing is feasible, safe, and superior to right ventricular pacing in routine clinical practice. Heart Rhythm. 2015 Feb;12(2):305-12. doi: 10.1016/j.hrthm.2014.10.021. Epub 2014 Oct 22.
Results Reference
background

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Impact of Left Bundle Branch Area Pacing vs. Right Ventricular Pacing in Atrioventricular Block (LEAP-Block)

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