Atrial Fibrillation Occurring Transiently With Stress (AFOTS)

Study Overview
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Brief Summary
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Rationale Atrial fibrillation (AF) often occurs transiently in the setting of an acute stressor (e.g. medical illness or surgery). Uncertainty exists as to whether AF Occurring Transiently with Stress (AFOTS) is secondary to a reversible precipitant and is benign, or is a first presentation of paroxysmal AF and associated with a risk of stroke. AFOTS is a common occurrence (>40% in some intensive care settings), but there is a lack of evidence to guide its management and guidelines have called for further research in this area. Retrospective data suggest that many patients with AFOTS (>50%) will experience recurrent AF. These estimates were obtained without using sensitive methods for AF detection, which raises the possibility that the true rate of recurrent AF is much higher. As the rate of recurrent AF increases, it becomes increasingly likely that AFOTS is just the first detection of typical clinical AF. Objective To use a sensitive strategy to determine the rate of recurrent AF among patients who experienced AFOTS following i) non-cardiac surgery OR ii) medical illness, compared to matched controls. Methods Two multi-centre, 138-patient, observational cohorts. AFOTS patients will have new AF, documented by 12-Lead ECG or surface monitoring, during hospitalization for non- cardiac surgery (Cohort 1) or medical illness (Cohort 2). Controls will be patients without a history of AF who are matched for age (within 5 years), sex and exposure to stressor. Participants will wear a 14-day ECG monitor at 1 and 6 months after discharge. The endpoint is detection of AF. Impact If the incidence of AF after AFOTS is >80%, clinicians could be advised to treat AFOTS like clinical AF and initiate anticoagulation according to guidelines. Otherwise, a strategy of surveillance for AF would be advised. Hypothesis Patients who experience AFOTS will have a higher future incidence of AF and of stroke compared to patients exposed to a similar stressor but who did not develop AF. The risk of recurrent AF after AFOTS will be sufficiently high (> 80%) to warrant routine initiation of long-term OAC in all cases.

Official Title
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Atrial Fibrillation Occurring Transiently With Stress (AFOTS): Understanding the Risks of Recurrent AF. Study in Non-cardiac Surgery and in Medical Illness Patients.

Conditions
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Atrial Fibrillation New Onset

Intervention / Treatment
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* Diagnostic Test: 14 Day ECG Patch (Zio XT Patch, iRhythm Technologies)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Cases will be patients without a history of AF who experience new AFOTS during hospital admission for non-cardiac surgery (non-cardiac surgery study) OR medical illness (medical illness study) Controls will be patients who were exposed to a similar stressor but did not develop AF (matched for age within 5 years, sex and stressor). All participants will have a CHA2DS2-VaSc score >1 for men, >2 for women. Exclusion Criteria: Documented prior history of AF. Patients whose rhythm is AF at the time of discharge from hospital Patients unsuitable for study follow-up because the patient: is unreliable concerning the follow-up schedule cannot be contacted by telephone has a life expectancy less than one year Unwilling or unable to participate in the study Presence of an implanted pacemaker or defibrillator. Documented significant allergy to ECG electrode adhesive. Residence in a chronic care facility Diagnosed with Ischemic Stroke or Systemic embolism on admission Primary cardiac admitting diagnosis (i.e. myocardial infarction, heart failure, pericarditis, arrhythmia) Patients with Stage V Chronic Kidney Disease

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| AFOTS - Medical Illness Cases<br>Patients who have AF detected for the first time in the setting of an acute non-cardiovascular medical (i.e. non-surgical ). 14 day patch ECG monitor at 1 month and 6 months after hospital discharge | Diagnostic Test: 14 Day ECG Patch (Zio XT Patch, iRhythm Technologies)<br>* The ZIO XT Patch (http://www.irhythmtech.com/zio-solution/zio-patch/) is an ultra-portable wearable adhesive patch monitor that provides continuous single-lead ECG recording for up to 14 days. It has been cleared by the FDA for arrhythmia detection and is in current clinical use in the U.S.[87]. It will be used in this study under an investigational testing authorization by Health Canada. The ZIO XT Patch is a single-use device worn over the left pectoral region with a skin adhesive (Figure 4). Its small, lightweight, water-resistant, patch-based design has advantages for patients compared with traditional ECG screening methods (e.g. Holter, event loop recorders, mobile outpatient telemetry systems), which are all more cumbersome and require detachable wired leads, two or more removable skin contact electrodes, plus separate recording units (+/- smartphone attachment).<br>|
| Medical Illness Controls<br>Patients without a history of AF who are hospitalized for an acute non-cardiovascular medical (i.e. non-surgical) and do not have AF detected. 14 day patch ECG monitor at 1 month and 6 months after hospital discharge | Diagnostic Test: 14 Day ECG Patch (Zio XT Patch, iRhythm Technologies)<br>* The ZIO XT Patch (http://www.irhythmtech.com/zio-solution/zio-patch/) is an ultra-portable wearable adhesive patch monitor that provides continuous single-lead ECG recording for up to 14 days. It has been cleared by the FDA for arrhythmia detection and is in current clinical use in the U.S.[87]. It will be used in this study under an investigational testing authorization by Health Canada. The ZIO XT Patch is a single-use device worn over the left pectoral region with a skin adhesive (Figure 4). Its small, lightweight, water-resistant, patch-based design has advantages for patients compared with traditional ECG screening methods (e.g. Holter, event loop recorders, mobile outpatient telemetry systems), which are all more cumbersome and require detachable wired leads, two or more removable skin contact electrodes, plus separate recording units (+/- smartphone attachment).<br>|
| AFOTS - Non-cardiac surgery Cases<br>Patients who have AF detected for the first time following non-cardiac surgery. 14 day patch ECG monitor at 1 month and 6 months after hospital discharge | Diagnostic Test: 14 Day ECG Patch (Zio XT Patch, iRhythm Technologies)<br>* The ZIO XT Patch (http://www.irhythmtech.com/zio-solution/zio-patch/) is an ultra-portable wearable adhesive patch monitor that provides continuous single-lead ECG recording for up to 14 days. It has been cleared by the FDA for arrhythmia detection and is in current clinical use in the U.S.[87]. It will be used in this study under an investigational testing authorization by Health Canada. The ZIO XT Patch is a single-use device worn over the left pectoral region with a skin adhesive (Figure 4). Its small, lightweight, water-resistant, patch-based design has advantages for patients compared with traditional ECG screening methods (e.g. Holter, event loop recorders, mobile outpatient telemetry systems), which are all more cumbersome and require detachable wired leads, two or more removable skin contact electrodes, plus separate recording units (+/- smartphone attachment).<br>|
| Non-cardiac Surgery Controls<br>Patients without a history of AF who are hospitalized after non-cardiac surgery and do not have AF detected. 14 day patch ECG monitor at 1 month and 6 months after hospital discharge | Diagnostic Test: 14 Day ECG Patch (Zio XT Patch, iRhythm Technologies)<br>* The ZIO XT Patch (http://www.irhythmtech.com/zio-solution/zio-patch/) is an ultra-portable wearable adhesive patch monitor that provides continuous single-lead ECG recording for up to 14 days. It has been cleared by the FDA for arrhythmia detection and is in current clinical use in the U.S.[87]. It will be used in this study under an investigational testing authorization by Health Canada. The ZIO XT Patch is a single-use device worn over the left pectoral region with a skin adhesive (Figure 4). Its small, lightweight, water-resistant, patch-based design has advantages for patients compared with traditional ECG screening methods (e.g. Holter, event loop recorders, mobile outpatient telemetry systems), which are all more cumbersome and require detachable wired leads, two or more removable skin contact electrodes, plus separate recording units (+/- smartphone attachment).<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Atrial Fibrillation >/=30 s |  | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time to Atrial Fibrillation | Among AFOTS patients with the primary endpoint detected by the ECG patch monitor: time to first detection of AF >30 s. | 1 year | 
| Daily and total AF burden | Among AFOTS patients with the primary endpoint detected by the ECG patch monitor: daily and total AF burden. | 1 year | 
| Average duration per AF episode | Among AFOTS patients with the primary endpoint detected by the ECG patch monitor: average duration per AF episode | 1 year | 
| Other durations of Atrial Fibrillation | Among AFOTS patients, occurence of any AF episode lasting ≥30 seconds, ≥30 seconds to 5 minutes, >5 hours, and >24 hours (to facilitate comparison with other studies in the literature).( within 12 months post-enrolment) | 1 year | 
| Atrial Fibrillation at 1 and 6 months | Detection of the primary outcome at 1 and 6 months post enrolment. | 1 and 6 months | 
| Other clinical outcomes | Incidence of Clinical outcome events within 12 months post-enrolment (death, stroke, bleeding, embolism and hospitalization for heart failure or myocardial infarction), physician visits, hospitalizations and medication prescriptions. | 1 year | 
| OAC Use | Oral anticoagulant therapy use | 1 year | 
| Cost-effectiveness | Cost-effectiveness (cost per life year saved) | 1 year | 
| Cost-utility | cost-utility (cost per quality adjusted life year (QALY) gained) of AF screening | 1 year | 
| Patient adherence | Patient adherence with the monitoring devices (defined as the average number of monitoring days completed and reasons for non-adherence) | 1 year | 
| Patient satisfaction | patient satisfaction with the monitoring devices (as measured by user satisfaction surveys), | 1 year | 
| Sensitivity and Specificity | Estimated sensitivity, specificity of non-patch ECG monitoring(i.e. monitoring done outside of the study protocol), with ZioXT ECG patch monitor as the gold standard | 1 year | 
| Other arrhythmias | Incidence of Detection of other potentially clinically important non-AF arrhythmias: atrial tachycardia, pause >3 seconds, high-grade atrioventricular block (Mobitz type II or third-degree AV block), ventricular tachycardia, polymorphic ventricular tachycardia/ventricular fibrillation. ( within 12 months post-enrolment) | 1 year |