An interventional study of BBAP on and BBAP off in Heart Failure and Reduced Ejection Fraction, sponsored by Seoul National University Hospital. Not yet recruiting. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-04-23.
Sponsored by Seoul National University Hospital · Not applicable, Interventional, and Treatment
To evaluate the effect of accelerated atrial resynchronization achieved through Bachmann bundle pacing at the time of implantable cardioverter-defibrillator implantation in patients with heart failure with reduced ejection fraction and interatrial block
Interatrial block (IAB) is a distinct electrocardiographic finding resulting from delayed conduction between the right and left atria through Bachmann's bundle (BB). In a prevalence study of non-hospitalized individuals aged 65 years or older in sinus rhythm, IAB was observed in 59% of participants. With population aging and improved survival among patients with cardiovascular comorbidities, the prevalence of IAB is expected to increase further. Importantly, IAB leads to delayed left atrial contraction and impaired left ventricular diastolic filling, pathophysiological features commonly observed in heart failure (HF) that contribute to worsening HF symptoms.
Bachmann bundle area pacing (BBAP) has emerged as an attractive alternative to conventional right atrial appendage (RAA) pacing. Recent studies have demonstrated that BBAP, when guided by intracardiac electrograms and implemented using sheath-assisted atrial lead implantation techniques, is a safe and feasible approach for effectively correcting IAB. Echocardiographic data have shown that BBAP induces biatrial resynchronization. In clinical studies involving patients with heart failure with preserved ejection fraction (HFpEF), BBAP has been associated with significant clinical benefits, including improvements in quality of life, increased physical activity, and reductions in NT-proBNP levels. In these HFpEF studies, the clinical effects of BBAP were evaluated using physiologically accelerated pacing (approximately 70 beats per minute or individualized fine-tuned accelerated pacing based on body size and left ventricular ejection fraction), with particularly notable benefits observed in the improvement of diastolic function.
Despite these promising findings, the role of BBAP and BBAP-mediated accelerated pacing in patients with heart failure with reduced ejection fraction (HFrEF) has not yet been clearly established. In animal (porcine) models, improvement in atrial synchrony achieved through BBAP has been shown to significantly increase left ventricular stroke volume compared with conventional RAA pacing, as confirmed by comprehensive hemodynamic analyses. However, despite the potential advantages of this more physiological pacing strategy, human data evaluating BBAP in patients with HFrEF remain limited.
Accordingly, the present study aims to evaluate the clinical effects of atrial resynchronization achieved through accelerated BBAP in patients with HFrEF accompanied by interatrial block who meet indications for implantable cardioverter-defibrillator implantation.
227 studies on the registry are indexed under Heart Failure, Systolic; 50 are open to participants now.
This study's planned enrollment of 120 is above the median of 60 across 162 interventional studies indexed under Heart Failure, Systolic.
Browse Heart Failure, Systolic studies →Seoul National University Hospital is the lead sponsor of 1,860 studies on the registry; 275 are open to participants now.
Of its 12 completed or terminated interventional studies of FDA-regulated products, 2 (17%) have results posted.
Counted across the registry records on this site, refreshed daily.
Receiving optimized guideline-directed medical therapy (GDMT) for heart failure with reduced ejection fraction (HFrEF), unless contraindicated or not tolerated:
NT-proBNP measured within 3 months prior to randomization meeting one of the following criteria:
Exclusion Criteria:
In the Bachmann bundle pacing ON group, the implantable cardioverter-defibrillator will be programmed for 6 weeks with a lower rate limit (LRL) of 70 beats per minute, DDDR mode, and atrial preference pacing (APP) enabled. After the initial 6-week randomized period, to eliminate the effects of prior pacing, the implantable cardioverter-defibrillator in both groups will be reprogrammed to an LRL of 30 beats per minute in VVI mode, followed by a 4-week washout period. After the washout period, participants will undergo crossover, such that those initially assigned to the Bachmann bundle pacing ON group will be switched to the OFF group, and those initially assigned to the OFF group will be switched to the ON group, with the assigned pacing mode maintained for an additional 6 weeks.
Device: BBAP on
In the Bachmann bundle pacing OFF group, the implantable cardioverter-defibrillator will be programmed for 6 weeks with an LRL of 30 beats per minute in VVI mode. After the initial 6-week randomized period, to eliminate the effects of prior pacing, the implantable cardioverter-defibrillator in both groups will be reprogrammed to an LRL of 30 beats per minute in VVI mode, followed by a 4-week washout period. After the washout period, participants will undergo crossover, such that those initially assigned to the Bachmann bundle pacing ON group will be switched to the OFF group, and those initially assigned to the OFF group will be switched to the ON group, with the assigned pacing mode maintained for an additional 6 weeks.
Device: BBAP off
A comparator cohort receiving accelerated atrial resynchronization via right atrial appendage pacing will be enrolled separately at institutions distinct from those recruiting participants for Bachmann bundle pacing. In the right atrial appendage pacing cohort, the implantable cardioverter-defibrillator will be programmed for the initial 6 weeks with an LRL of 70 beats per minute, DDDR mode, and atrial preference pacing enabled. Individualized adjustment of the LRL will be permitted at the investigator's discretion based on the patient's clinical status.
Drug: RAAP
ICD programmed for 6 weeks with LRL 70 beats/min, DDDR, and APP enabled.
ICD programmed for 6 weeks with an LRL 30 beats/min in VVI mode
ICD programmed for 6 weeks with LRL 70 beats/min, DDDR, and APP enabled.
Relative change in NT-proBNP at 6 weeks (accelerated Bachmann bundle area pacing ON) compared with baseline (accelerated Bachmann bundle area pacing OFF).
Time frame: up to 6 weeks
Change in Kansas City Cardiomyopathy Questionnaire (KCCQ) score at 6 weeks, 16 weeks, and 12 months compared with baseline.
Time frame: up to 12 months
Changes in E and A wave velocity (m/s) on echocardiography at 6 weeks, 16 weeks, and 12 months compared with baseline.
Time frame: up to 12 months
Changes in E/A and E/E' ratios on echocardiography at 6 weeks, 16 weeks, and 12 months compared with baseline.
Time frame: up to 12 months
Change in left atrial diameter (mm) on echocardiography at 6 weeks, 16 weeks, and 12 months compared with baseline.
Time frame: up to 12 months
Change in left atrial strain (%) on echocardiography at 6 weeks, 16 weeks, and 12 months compared with baseline
Time frame: up to 12 months
Change in left atrial volume index (LAVI, ml/m2) on echocardiography at 6 weeks, 16 weeks, and 12 months compared with baseline.
Time frame: up to 12 months
Change in left ventricular ejection fraction (LVEF) at 6 weeks, 16 weeks, and 12 months compared with baseline.
Time frame: up to 12 months
Change in NYHA functional class at 6 weeks, 16 weeks, and 12 months.
Time frame: up to 12 months
Change in peak oxygen consumption (VO₂ max) at 6 weeks, 16 weeks, and 12 months compared with baseline.
Time frame: up to 12 months
Incidence of newly detected atrial fibrillation (AF).
Time frame: up to 12 months
Atrial fibrillation (AF) burden (%)
Time frame: up to 12 months
Change in 6-minute walk distance (6MWD) compared with baseline.
Time frame: up to 12 months
The occurence of clinical outcomes at 12 months, including: a) All-cause mortality, b) Worsening heart failure, regardless of hospitalization*, and c) Composite outcome of (a) and (b)
\* Worsening heart failure is defined as deterioration in symptoms, signs, imaging, or laboratory findings requiring unplanned medical intervention, including up-titration of oral diuretics or administration of intravenous diuretics.
Time frame: up to 12 months
No study locations are listed for this record.
Plan to share: Undecided
No publications or documents are linked to this record.
This study is not yet recruiting, as verified in Apr 2026. You cannot join it, but the record below documents what was studied.
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Seoul National University Hospital