Smartwatch and External Holter Monitoring to Detect Atrial Fibrillation in Patients With Cryptogenic Stroke

This trial is comparing a consumer smartwatch with a traditional external heart monitor (Holter monitor) to detect atrial fibrillation (an irregular heart rhythm) in stroke survivors where the cause of the stroke is unknown. Finding hidden atrial fibrillation after a stroke is important because it changes treatment — these patients need blood thinners to prevent another stroke. **You may be eligible if...** - You are 55 years of age or older - You have been diagnosed with a cryptogenic stroke (a stroke where no clear cause was found) after a standard workup - Your disability from the stroke is mild (Modified Rankin Scale score below 4) **You may NOT be eligible if...** - Your stroke was a small lacunar infarct or a TIA (mini stroke) - A clear cause was already found for your stroke (known atrial fibrillation, significant artery narrowing, blood clot from the heart, or a clotting disorder) - You already have a pacemaker - You are unwilling to wear cardiac monitoring devices - Your circumstances would make follow-up difficult Talk to your doctor to see if this trial is right for you.