• HF patients with AF within the past 12 months

• HF is defined as all of the below (all must apply)

⁃ Clinically assessed Heart Failure with Reduced Ejection Fraction (HFrEF)

⁃ An indication for initiation or ongoing guideline directed medical therapy for HFrEF, according to current Heart Failure guidelines

⁃ LVEF \< 50% at any point during the past 12 months

• AF is defined as one or more of the following:

• A. Symptomatic AF, documented by ECG, Holter of CIED

• B. Asymptomatic AF with one or more of the following:

⁃ Clinical indication for rhythm or rate control (documented by ECG, telemetry, Holter, CIED)

⁃ ≥2 ECG detected AF episodes within 3 months (on separate dates)

⁃ Holter detected AF with a continuous duration of more than 6 hours

⁃ CIED detected AF with continuous duration \>24 hours

• 18 years ≤ Age \<80 years

• Optimal medical therapy for HFrEF or planned/current uptitration in guideline directed medical therapy for HFrEF

• Treatment with anticoagulation for stroke prevention, initiated according to guidelines for treatment of AF