LBBAP vs. CS Pacing for CRT in Permanent Atrial Fibrillation and Heart Failure (SYNC-AF)
Trial statusNot yet recruiting
Trial phaseNot applicable
Trial typeInterventional
Biological sexAll
Age19+
SponsorYonsei University
About this trial
This is a prospective, multicenter, randomized controlled trial comparing Left Bundle Branch Area Pacing (LBBAP)-based cardiac resynchronization therapy (CRT) with conventional coronary sinus (CS) lead-based CRT in patients with permanent atrial fibrillation (AF) and heart failure (HF) who meet indications for CRT device implantation.
Atrial fibrillation and heart failure frequently coexist, and both rapid heart rate and its irregularity contribute to worsening cardiac function. Atrioventricular junction (AVJ) ablation combined with CRT (biventricular pacing) has been established as an effective strategy for rate control and cardiac resynchronization in this population, supported by Class I recommendation in the 2021 ESC guidelines. However, conventional biventricular CRT via the CS lead can induce artificial electrical dyssynchrony, particularly in patients with a narrow QRS complex, potentially limiting its benefit.
Conduction system pacing (CSP), including LBBAP, has emerged as a physiologic alternative that directly stimulates the native conduction system, preserving synchronous ventricular activation. Recent evidence (ALTERNATIVE-AF trial) suggests CSP may be superior to biventricular CRT in permanent AF patients undergoing AVJ ablation. However, no randomized controlled trial has directly compared LBBAP-based CRT with CS lead-based CRT in this specific population.
The SYNC-AF trial will randomize 44 patients (22 per arm) to either LBBAP or CS pacing for CRT. The primary endpoint is change in left ventricular ejection fraction (LVEF) at 12 months as assessed by echocardiography in a blinded core laboratory. Secondary endpoints include changes in QRS duration, major adverse clinical events, device/procedure-related complications, and ventricular arrhythmia burden.
Eligibility criteria
This trial does not accept healthy volunteersQualifiers
Age ≥19 years
Indication for CRT (CRT-P or CRT-D) device implantation per current guidelines
Permanent atrial fibrillation (with or without planned AVJ ablation)
Ability to understand the purpose of the study and provide written informed consent
Disqualifiers
Prosthetic tricuspid valve
Prior myocardial infarction involving the interventricular septal area
Life expectancy less than 12 months
Unable to comply with planned 12-month follow-up for any reason
Trial design
Design model
Parallel
Treatments tested in this trial
Left Bundle Branch Area Pacing (LBBAP) for CRT
DeviceCRT device (CRT-P or CRT-D) implantation using LBBAP as the left ventricular pacing lead. A pacing lead is advanced through the interventricular septum to achieve left bundle branch area capture, confirmed by pacing parameters and electrocardiographic criteria (RBBB-like pattern with short R-peak latency in V5/V6). RV lead is implanted in standard fashion. AVJ ablation may be performed per clinical indication.
Coronary Sinus (CS) Lead-Based Biventricular CRT
DeviceCRT device (CRT-P or CRT-D) implantation using a conventional coronary sinus (CS) lead as the left ventricular pacing lead. The CS lead is advanced via the coronary sinus into a lateral or posterolateral cardiac vein to achieve biventricular pacing. RV lead is implanted in standard fashion. AVJ ablation may be performed per clinical indication.
Treatment groups
44 Participants
are divided into 2 treatment groupsGroup A: LBBAP GroupExperimental treatment 1 intervention
Group B: CS Pacing GroupActive comparator 1 intervention
Trial outcomes
Primary outcomes
1
Change from Baseline Left Ventricular Ejection Fraction (LVEF) at 12 Months
Change in left ventricular ejection fraction (LVEF) from baseline to 12 months post-implantation, as measured by transthoracic echocardiography performed and interpreted by a blinded independent central core laboratory. LVEF is assessed using the biplane Simpson method.
Time frame
Baseline (at the time of device implantation) and 12 months post-implantationSecondary outcomes
1
Proportion of patients with absolute LVEF increase ≥5% at 12 months
Echocardiographic CRT response defined as absolute improvement in LVEF of ≥5% or ≥10% from baseline at 12 months, assessed by blinded core lab.
Time frame
12 months post-implantation2
Proportion of patients with absolute LVEF increase ≥10% at 12 months
Echocardiographic CRT response defined as absolute improvement in LVEF of ≥5% or ≥10% from baseline at 12 months, assessed by blinded core lab.
Time frame
12 months post-implantation3
Change in QRS Duration From Baseline
QRS duration measured from surface ECG in milliseconds.
Time frame
Immediately post-implant and at 12 months4
Time to First Treated Ventricular Arrhythmia
Time from randomization to first detection of treated ventricular arrhythmia (VT/VF) recorded by the implanted device within 12 months.
Time frame
Up to 12 monthsLocations
Sponsors and contacts
Click on the lead sponsor to view all of their trials.
Source ClinicalTrials.gov
This trial is not recruiting at the moment. You can still explore other options: