Pacing of Left Bundle Branch Area and Atroventricular Node ablatIon in Patients With Symptomatic Atrial Fibrillation

• Multicenter, randomized, open-label clinical trial
• Randomization 1:1 fashion A randomly permuted-block randomization list was generated by computer at a central location and was stratified by center.
• Study duration:

• 6 months (for primary outcome)
• 24 months (for secondary outcomes)
• Study subjects number: 50 patients (25 patients per group)
• Procedures

• Atrioventricular node ablation after successful left bundle branch area pacing at the same procedure time.
• Left bundle branch area pacing will be performed in all patients (using lumenless or stylet-driven lead, on the operator's discretion)
• Atrioventricular node ablation will be performed using the quadripolar 7-Fr 3.5-mm tip ablation catheter and the use of 8.5-F sheath (SR0 or SL1, St. Jude Medical Inc., St. Paul, MN, USA) depending on the operator's experience, and if not stable or failed, a deflectable sheath (Agilis, Abbott Electrophysiology, Menlo Park, CA, USA) will be used. Repeated ablation procedures will be recommended during follow-up if regression of atrioventricular block has occurred.
• Immediately after implant, devices were programmed to achieve the shortest QRS duration. Unipolar pacing was initially used to determine left bundle branch capture.

Inclusion:

Patients who meet all of the following inclusion criteria 1)-6).

• Permanent atrial fibrillation
• Age ≥ 65 years
• Refractory or intolerant to antiarrhythmic drugs, rate control medications, or catheter ablation
• New York Heart Association (NYHA) functional class II- IV
• LVEF > 40% (within the past 3 months)
• Patients with at least one of the following:

• HF hospitalization (defined as HF as the major reason for hospitalization or treatment for HF lasting ≥12 hours and including treatment with intravenous (IV) diuretics at a healthcare facility) within 12 months
• Elevated NT-proBNP (>900 pg/ml) in the 30 days prior to enrollment

Exclusion:

Patients who meet at least one of the following exclusion criteria 1)-11).

• Asymptomatic atrial fibrillation
• Life expectancy to < 12 months.
• Primary moderate to severe valvular disease (except for functional mitral valve regurgitation or tricuspid valve regurgitation)
• Mechanical tricuspid valve replacement
• Severe chronic kidney disease (estimated Glomerular Filtration Rate ≤ 15 ml/1,73 m2 or receiving renal replacement treatment including hemodialysis or peritoneal dialysis)
• Obstructive hypertrophic cardiomyopathy
• Infiltrative cardiomyopathy (amyloidosis, sarcoidosis, Fabry disease, others)
• Acute coronary syndrome or coronary revascularization (CABG or PCI) <3 months
• Severe primary pulmonary disease such as cor pulmonale, irreversible lung disease requiring inhalers, oxygen supplementation
• Pacemaker/ICD/CRT treatment ongoing, or current pacemaker indication
• Simultaneous participation in a different randomized clinical trial