DETECTion of PeriOperative Atrial Fibrillation After Noncardiac Surgery

Inclusion Criteria: 1. Had undergone noncardiac surgery within the past 72 hours and requiring, or expected to require, at least one of the following: * an overnight hospital admission after surgery * day surgery that would result in a large enough physiological insult to be able to cause POAF. Procedures excluded include those that are conducted using local anesthesia alone, are less than 30 minutes in duration, and/or are judged to be of low physiologic insult by the local investigator. 2. Have one of the following high-risk criteria; * age 55-64 years, and having either established cardiovascular disease, recent major vascular surgery, a CHA2DS2-VASc score ≥3, or an elevated postoperative troponin level; * age 65-74 years, and having either established cardiovascular disease, recent major vascular surgery, a CHA2DS2-VASc score ≥2, or an elevated postoperative troponin level; or * age ≥75 years; 3. Provide written informed consent to participate. Exclusion Criteria: 1. History of documented chronic (i.e., non-transient) AF before noncardiac surgery; 2. Need for long-term systemic anticoagulation; 3. Ongoing need for long-term dual antiplatelet treatment; 4. Contraindication to oral anticoagulation; 5. Severe renal insufficiency; 6. Severe liver cirrhosis; 7. Acute stroke in the past 14 days; 8. Underwent cardiac surgery in the past 35 days; 9. History of nontraumatic intracranial, intraocular, or spinal bleeding; 10. Hemorrhagic disorder or bleeding diathesis; 11. Known life expectancy \<1 year due to concomitant disease; 12. Women who are pregnant, breastfeeding, or of childbearing potential not taking effective contraception; 13. Expected to be non-compliant with follow-up and/or device use; 14. Known contact allergy to monitoring device and/or its peripheral components; 15. Previously enrolled in DETECT-POAF.