The goal of this clinical trial is to learn if conduction system pacing works as well as cardiac resynchronization therapy (CRT) post atrioventricular (AV) node ablation in adult patients with symptomatic heart failure and atrial fibrillation that is not suitable for rhythm control.
The main question it aims to answer is:
Is AV node ablation with conduction system pacing noninferior to AV node ablation with CRT for the hierarchical composite outcome of all-cause mortality, heart failure hospitalization or urgent heart failure visit, and meaningful improvement in heart failure-related quality of life?
Participants will undergo:
* An AV node ablation and be randomly assigned to receive either a conduction system pacing or a CRT.
* Attend follow-up visits (in clinic or by telephone) at baseline, intervention day, 3-month, 12-month, 24-month, and 36-month after the procedure.
* Complete questionnaires about heart failure symptoms and quality of life at baseline, 12 months, and yearly.
* Have an echocardiogram, an electrocardiogram, and blood tests at baseline and 1 year
* At selected centers: they will be asked to wear a bracelet that measures arterial stiffness for 30 minutes and provide a urine sample at baseline and 1 year.