An interventional study of Left bundle branch area pacing and Right ventricular pacing in Bradyarrhythmia, Atrioventricular Block and Left Bundle Branch Area Pacing, sponsored by Yonsei University. Recruiting at 8 sites in South Korea. Open to participants aged 19 Years and older. Per ClinicalTrials.gov, last updated 2026-01-05.
Sponsored by Yonsei University · Not applicable, Interventional, and Treatment
PROTECT-SYNC study is a multicenter, randomized, controlled trial. A total of 7 medical centers across Republic of Korea will enroll 450 patients during 2 years of enrollment period, and followed for 2 years of follow-up period. The purpose of this study to compare the clinical outcomes of Left Bundle Branch Area Pacing (LBBAP) compared to Right Ventricular Pacing (RVP) in bradyarrhythmia patients who require high burden of ventricular pacing (>40%).
PROTECT-SYNC study is a multicenter, randomized, controlled trial that is designed to assess whether LBBAP may reduce the risk of composite primary endpoint including all cause mortalty, HF hospitalization and/or urgent HF related visit, occurrence of pacing induced CMP, and CRT-upgrade event, compared to RVP in patients who require substantial (>40%) ventricular pacing. Patients who require pacemaker and substantial (>40%) ventricular pacing will be randomized to LBBAP or RVP group, and a total of 7 medical centers across Republic of Korea will enroll 450 patients during 2 years of enrollment period, and followed for 2 years of follow-up period.
317 studies on the registry are indexed under Bradycardia; 71 are open to participants now.
This study's planned enrollment of 450 is above the median of 100 across 187 interventional studies indexed under Bradycardia.
Browse Bradycardia studies →Yonsei University is the lead sponsor of 1,418 studies on the registry; 241 are open to participants now.
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Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
3 Scheduled to receive a pacemaker implant 4. Substantial percentage of V pacing rate (>40%) is anticipated
Exclusion criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Life expectancy
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
In this arm, a left bundle branch area pacing(LBBAP) lead will be attempted to be placed.
Procedure: Left bundle branch area pacing
In this arm, a Right ventricular pacing (RVP) lead will be attempted to be placed.
Procedure: Right ventricular pacing
LBBAP success is defined if ventricular lead is successfully placed at interventricular septum and RBB configuration observed during unipolar tip pacing. LBB capture is defined if fulfilling criterion 1 and at least one in criteria 2. 1. RBBB configuration observed during unipolar tip pacing 2. One of the following should be met: 1. Abrupt shortening of Stim-LVAT (stimulus to peak of the R wave in V6 \[LV activation time\]) of \>10ms during increasing output 2. Short and constant stim-LVAT and the shortest stim-LVAT \<75ms in non-LBBB and \<85ms in LBBB 3. Programmed stimulation by pacing lead changes QRS morphology from nonselective LBB to LV septal capture 4. LBB potential (LBB-V interval of 15 to 35ms) 5. Transition from nonselective LBB capture to selective LBB capture at near threshold outputs If criterion 1 is fulfilled but none in criteria 2 is met, the procedure is considered to be deep septal pacing (DSP).
Right ventricular pacing is the traditional pacing modality for ventricular pacing. Implantation of a RV pacing lead (apex or septum of right ventricle) will be attempted using the standard-of-care technique first
composite of all-cause death, heart failure hospitalization, occurrence of pacing induced cardiomyopathy, and an upgrade to cardiac resynchronization therapy
All-cause death: including cardiovascular and non-cardiovascular deaths. Heart failure hospitalization: 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 intravenous therapy. Occurrence of Pacing induced cardiomyopathy : LVEF \<50% and absolute LVEF decline ≥10% or increase in LVESV ≥15% Upgrade to cardiac resynchronization therapy (CRT): Upgrade from pacemaker to CRT-Pacemaker/CRT-Defibrillator due to impaired LV function (LVEF decrease to 40% or less).
Time frame: during 2 years after pacemaker implantation
all cause mortality
All cause deaths including cardiovascular and non-cardiovascular deaths.
Time frame: during 2 years after pacemaker implantation
Cardiovascular mortality
Cardiovascular death
Time frame: during 2 years after pacemaker implantation
Heart failure hospitalization
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 intravenous therapy.
Time frame: during 2 years after pacemaker implantation
success rate of LBBAP implantation
LBBAP success is defined if ventricular lead is successfully placed at interventricular septum and RBB configuration observed during unipolar tip pacing.
Time frame: during 3days after pacemaker implantation
LBBAP related complications
Loss of lead function or need for lead revision, extraction, replacement for any reason
Time frame: during 2 years after pacemaker implantation
LBB capture failure
failed LBB capture, confirmed by investigator
Time frame: during 2 years after pacemaker implantation
Short-term procedure and Device related complications
composite of device and procedure related complications until 7 days after procedure
Time frame: during 1wk after pacemaker implantation
Long-term procedure and Device related complications
composite of device and procedure related complications after 7 days after procedure
Time frame: during 1wk after pacemaker implantation
Rate of LV systolic dysfunction
LVEF \<50% and absolute reduction in LVEF \>10%, and/or an increase in LVESV ≥15%.
Time frame: 6month and 2yr after pacemaker implantation
Changes in cardiopulmonary exercise test parameters
(VO2 peak, Exercise intensity, Peak Respiratory Exchange Ratio (Peak RER), Exercise time, age predicted aerobic capacity, VE/VCO2 slope, Lactate threshold, Max predicted HR, Max HR / Max predicted HR, presence of ST change , AF at Baseline, Incident AF during exercise
Time frame: 6month and 2yr after pacemaker implantation
Incidental atrial fibrillation
Newly developed atrial fibrillation in patients without documented atrial fibrillation
Time frame: during 2 years after pacemaker implantation
Plan to share: No
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