Comparison of Pacing Lead Design on Left Bundle Branch Pacing Outcomes: The LEAD_LBBP Randomized Clinical Trial (LEAD-LBBP)

Comparison of Pacing Lead Design on Left Bundle Branch Pacing Outcomes

This trial seeks to evaluate the performance of the extendable helix, stylet-driven pacing lead (SDL) compared to the fixed helix, lumenless pacing lead (LLL) during left bundle branch pacing (LBBP), with respect to enduring left bundle branch capture on follow-up, incidence of acute lead failure, pacing characteristics including QRS duration, pacing thresholds, R-wave amplitudes and lead impedance, and finally, safety profile during LBBP implantation. These data will guide future lead selection during LBBP implantation in achieving improved procedural success and optimal lead performance.

Study Overview

• Status: Active, not recruiting
• Conditions: Pacemaker DDD
• Intervention / Treatment: Device: Fixed helix, lumenless pacing lead.; Device: Extendable helix, stylet-driven pacing lead.

Detailed Description

This study is a single-blind, randomised controlled trial, aimed at evaluating the performance of the extendable helix, stylet driven pacing lead (SDL) compared to the fixed helix, lumenless pacing lead (LLL) during left bundle branch pacing (LBBP). The study is a multicentre study across 3 major hospitals in Singapore, and LBBP performed by independent electrophysiologists experienced in performing LBBP.

The primary objective of the study is to determine differences in incidence of loss of left bundle capture by pacing lead design (LLL vs SDL). The secondary objectives are to determine if lead design affects frequency of lead failure during implantation, investigate differences in short- and medium-term LBBP parameters on follow-up by lead design, and evaluate differences in safety profile between LLL and SDL in LBBP.

This study aims to recruit a target of 210 patients. A previous retrospective study found a loss of LB capture rate of 9% with LLL and 25% with SDL. A sample size of 170 will be required for a type-1 error rate of 5% and power of 80%. Accounting for a dropout rate of 20%, a total of 210 patients will be recruited (105 per group). Eligible subjects will be randomised to either the LLL or the SDL arm. The randomisation list will be generated with a computer-generated sequence in permuted blocks of 4, stratified by centre, to ensure a final allocation ratio of 1:1.

• Study Type: Interventional
• Enrollment (Estimated): 210
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Singapore
  • Singapore, Singapore
    • National University Heart Centre Singapore

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

1. Fulfil current indications for pacemaker therapy according to international guideline recommendations:

   1. Symptomatic sinus bradycardia/sinus node dysfunction or AV block requiring pacemaker insertion.
   2. Symptomatic heart failure, left ventricular ejection fraction (LVEF) <35%, left bundle branch block and QRS duration >120ms.
   3. Symptomatic heart failure, left ventricular ejection fraction (LVEF) <35%, right bundle branch block and QRS duration >150ms.
   4. LVEF <50% with significant anticipated ventricular pacing requirement of ≥20%.
2. Age ≥21 years old
3. Able to provide informed consent
4. Planned LBBP implantation

Exclusion Criteria:

1. Severe tricuspid regurgitation or previous tricuspid valve intervention requiring implantation of left ventricular lead in the coronary sinus.
2. Unable to provide informed consent.
3. Pregnant women.
4. <21 years of age.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Fixed helix, lumenless pacing lead (FHL); Lumenless leads used are fixed helix pacing leads (SelectSecure 3830 pacing lead from Medtronic) during the LBBP procedure.	Device: Fixed helix, lumenless pacing lead.; Patients will be randomised to the fixed helix, lumenless pacing lead design during LBBP implantation.
Active Comparator: Extendable helix, stylet-driven leads (EHL); Stylet-driven leads used are extendable helix pacing leads (Biotronik Solia S60 lead from Biotronik or Tendril STS pacing lead from St. Jude Medical) during the LBBP procedure.	Device: Extendable helix, stylet-driven pacing lead.; Patients will be randomised to the extendable helix, stylet-driven pacing lead design during LBBP implantation.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of loss of left bundle branch capture	Loss of LBB capture is defined as the absence of the terminal r/R' complex in V1 during initial threshold interrogations at high pacing outputs and the absence of transitions in paced QRS morphology with decreasing pacing outputs until loss of myocardial capture.	12 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of acute lead failure	Acute lead failure is defined as defined as structural damage to the pacing lead during implant necessitating the use of a new pacing lead.	12 months
Serial changes in pacing thresholds (V)	To compare the differences in pacing thresholds (V) at implant and at 12 months after LBBP implant.	12 months
Serial changes in R-wave amplitude (mV)	To compare the differences in R-wave amplitude (mV) at implant and at 12 months after LBBP implant.	12 months
Serial changes in lead impedance (ohm)	To compare the differences in lead impedance (ohm) at implant and at 12 months after LBBP implant.	12 months
Serial changes in QRS duration (ms)	To compare the differences in QRS duration (ms) at implant and at 12 months after LBBP implant.	12 months
Incidence of peri-procedural complications	Complications intraprocedurally and on follow-up will be evaluated, including lead dislodgement, lead fracture during implant, septal perforation, septal vein/arterial injury, pneumothorax, pericardial effusion, wound/pacemaker infection.	12 months

Collaborators and Investigators

• Sponsor: National University Hospital, Singapore
• Investigators: Principal Investigator: Eugene Tan, MBBS, NUHS

Study record dates

Study Major Dates

• Study Start (Actual): January 1, 2023
• Primary Completion (Estimated): October 19, 2025
• Study Completion (Estimated): October 19, 2025

Study Registration Dates

• First Submitted: February 6, 2024
• First Submitted That Met QC Criteria: March 12, 2024
• First Posted (Actual): March 19, 2024

Study Record Updates

• Last Update Posted (Actual): June 6, 2025
• Last Update Submitted That Met QC Criteria: June 3, 2025
• Last Verified: May 1, 2025

More Information

Terms related to this study

• Keywords: Left bundle branch pacing; Conduction system pacing; Lead design
• Other Study ID Numbers: LEAD-LBBP

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No