Conduction System Pacing and AV Junction Ablation in Heart Failure With Atrial Fibrillation (SYNC AF-HTx)

End-stage heart failure patients often face a poor prognosis due to comorbid permanent AF, which leads to irregular heart rates and worsens ventricular function. While implantable cardioverter-defibrillators (ICDs) are standard for preventing sudden cardiac death, they may not sufficiently prevent heart failure progression in patients with narrow QRS complexes. This study explores a "SYNC" strategy using LBBP and AVJ ablation to achieve ventricular synchronization and heart rate regularization. This is a multicenter, prospective, randomized (1:1), single-blind trial involving 120 participants.

Inclusion criteria

Participants must have LVEF≤35%, permanent AF for >6 months, and be eligible for ICD implantation while awaiting heart transplantation or LVAD.

Intervention (SYNC Group): Participants receive an ICD with an LBBP lead (Medtronic SelectSecure™ 3830) and undergo AVJ ablation.

Control Group: Participants receive standard ICD implantation with a minimal ventricular pacing setting.

Follow-up: Clinical assessments, echocardiography, and device profiles will be monitored at baseline, 1, 3, 6, and 12 months post-procedure.

Inclusion criteria

Candidates for ICD implantation (primary or secondary prevention). Permanent AF (>6 months) unsuitable for or failed catheter ablation. End-stage heart failure considering heart transplant or LVAD. LVEF ≤ 35 within 6 weeks before enrollment. NYHA functional class ≥ II. On GDMT for at least 3 months. Age ≥ 19 years.

Exclusion criteria

Existing LVAD or prior heart transplantation. Indications for cardiac resynchronization therapy (CRT). History of mechanical tricuspid valve replacement. Expected survival≤ 12 months. Inability to comply with the study protocol.