This research is being done to assess whether it is safe and effective to stop oral anticoagulation medications (a blood-thinning medication) during prolonged periods of normal heart rhythm in participants with infrequent episodes of atrial fibrillation (AF).

You may qualify for this study if you have a history of atrial fibrillation (AF) and are currently taking an oral anticoagulant (a blood-thinning medication). You will be randomized to one of two groups: Control Group or Study Intervention Group.

If you are randomized to the Control group, you will be asked to stay on your previously prescribed oral anticoagulant. If you are randomized to the Study Intervention group, you will be asked to take the oral anticoagulant for 30 days only if a prolonged episode of AF is detected on an AF-sensing Apple smartwatch you will be provided.

This study's objective is to determine if electrical stimulation can safely reduced atrial fibrillation, which is an abnormal heart rhythm that begins in the top chambers of the heart. Electrical stimulation will be delivered to the wrists or in the ear. Participation will last about 6 weeks and require 3 clinic visits. Participants will be asked to wear a heart monitor and patch to monitor the heart rate and rhythm, keep a diary to collect information on atrial fibrillation, undergo randomization (being randomly assigned, like drawing straws) and use the study device per randomization assignment. Participants are randomized in a 1:1:1 fashion to a wrist worn study device, an ear piece study device or a sham wrist worn study device. A sham device looks like the real wrist worn device but does not deliver any electrical stimulation.