This is a multicentre prospective cohort study where patients will receive up to 14 days of continuous ECG monitoring by wearing a portable monitoring device, starting within 72 hours after noncardiac surgery.

POAF commonly occurs after noncardiac surgery and is associated with adverse long-term outcomes. Despite this, patients with POAF are routinely being missed during clinical practice. Continuous ECG monitoring has the potential to enhance POAF detection and improve clinical care in affected patients. Based on this background, the DETECT-POAF study will determine the incidence of clinically important POAF in those receiving up to 14 days of continuous ECG monitoring within 35 days 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.

Adults who have undergone noncardiac surgery