Inclusion Criteria:  

• Age ≥ 21 years.
• First-detected atrial fibrillation (defined as  diagnosed in the previous 120 days).
• Acute care encounter for evaluation or treatment of atrial fibrillation, within 120 days.
• Electrocardiographic documentation of atrial fibrillation. 
• Estimated life expectancy of at least 1 year.
• Patient or legal authorized representative capable of giving signed informed consent, which includes compliance with the requirements and restrictions listed in the informed consent form (ICF) and in this protocol.

Exclusion Criteria:  

• Age < 21 years old.
• First-Detected AFib > 120 days ago.
• No Acute Care Encounter for the diagnosis of first-detected AFib.
• Estimated life expectancy < 1 year.
• Patients with prior or planned treatment with rhythm control, either catheter ablation or antiarrhythmic drug therapy.
• Prior hospitalization for atrial fibrillation (other than the qualifying event).
• Planned cardiothoracic surgery.
• New York Heart Association class III or IV heart failure or a hospitalization for heart failure in the last 4 weeks.
• Patients with reduced ejection fraction (LVEF ≤ 40%).
• Permanent atrial fibrillation.
• Ineligible for oral anticoagulation, unless CHA2DS2-VASc is less than 3 in women or 2 in men.
• Bradycardia with a resting heart rate < 50 bpm.
• PR interval > 280 msec or 2nd degree or 3rd degree atrioventricular block without a permanent pacemaker/cardiac implanted electronic device.
• Corrected QT interval ≥ 500 msec.
• Pregnancy or breast feeding.
• Severe hepatic impairment in the opinion of the investigator.
• Other: (specify reason).

Note: Other protocol defined Inclusion/Exclusion Criteria may apply.

Eligibility last updated 1/18/23. Questions regarding updates should be directed to the study team contact.