30-Day Cardiac Event Monitor Belt for Recording Atrial Fibrillation After a Cerebral Ischemic Event
30-Day Cardiac Event Monitor Belt for Recording Atrial Fibrillation After a Cerebral Ischemic Event
Atrial fibrillation is the most common cardiac cause of ischemic stroke. Detecting atrial
 fibrillation after a stroke or TIA is critical because highly effective secondary stroke
 prevention therapy is available for individuals who are recognized to have atrial
 fibrillation. However, atrial fibrillation is likely under-diagnosed after stroke and TIA
 because atrial fibrillation is often difficult to detect as it is frequently paroxysmal and
 asymptomatic, and patients do not routinely undergo prolonged screening. The purpose of this
 study is to determine the diagnostic yield of a novel 30-day cardiac event monitor compared
 to a repeat 24-hour Holter monitor for detecting occult paroxysmal atrial fibrillation in
 patients with a recent ischemic stroke or TIA of undetermined etiology after completion of a
 standard clinical stroke work-up (including an initial negative Holter monitor.)
Inclusion:

 1. Diagnosis of the index event* made by a stroke specialist of an acute ischemic stroke
 or TIA (WHO definition) of undetermined etiology (cryptogenic) occurring within the
 previous 6 months (180 days).The event must be either:

 -  an embolic arterial ischemic stroke confirmed by neuroimaging; or

 -  a transient ischemic attack, defined as involving a focal unilateral motor
 deficit, speech/language deficit, or hemianopia, with symptom duration <24 hours
 (note: amaurosis fugax/transient monocular blindness, pure sensory spells,
 isolated vertigo spells, etc. do not qualify for enrolment given the potential
 for misdiagnosis of such events).

 2. Patient meets the following:

 -  At least one 12-lead ECG has already been obtained as part of the routine
 clinical post-stroke/TIA work-up, and no ECGs have shown any episodes of atrial
 fibrillation or atrial flutter, and;

 -  A Holter monitor has already been obtained as part of the routine clinical
 post-stroke/TIA work-up, and does not show any episodes of atrial fibrillation or
 atrial flutter ≥30 seconds.

 3. The patient is being actively investigated for the etiology of the stroke/TIA event
 and additional cardiac monitoring is desired to screen further for the possibility of
 occult paroxysmal atrial fibrillation/flutter, i.e. patients selected for this study
 are those for whom the investigator, in his/her clinical judgment, would consider
 ordering a repeat Holter monitor as part of clinical care.

 4. The following diagnostic tests have already been completed as part of clinical routine
 post-stroke/TIA:

 -  brain imaging with CT or MRI,

 -  vascular imaging of the extracranial and intracranial circulation with either CT
 angiography or MR angiography to exclude significant large vessel occlusive
 disease as the most likely mechanism for the index ischemic event (carotid
 Doppler ultrasound is acceptable for those presenting with anterior circulation
 ischemic events),

 -  transthoracic (or transesophageal) echocardiography to exclude thrombus or other
 structural heart disease that in the opinion of the investigator is the most
 likely cause for the stroke/TIA event. [Note: If a baseline echocardiogram cannot
 be obtained clinically after the index event and prior to study enrollment, then
 it is acceptable for study purposes for an echocardiogram to be obtained after
 patient enrollment into the study but prior to the 90-day follow-up visit.
 Alternatively, an echocardiogram already performed within one year prior to study
 enrollment may serve as the baseline echocardiogram for study purposes.]

 5. Age 55 years or older [Note: Participants aged 55-59 years should have imaging
 confirmation of the index stroke/TIA event with an embolic imaging pattern of acute
 cerebral ischemia]

 6. Informed consent from the patient (or from a legally authorized representative if the
 patient is not competent, e.g. due to stroke-related cognitive impairment, aphasia, or
 anosognosia).

 7. The patient is expected to survive at least 6 months.

 8. The patient has a valid provincial health insurance number.

 -  The index event will be defined as the event leading to medical presentation

 Exclusion:

 1. Any previously documented atrial fibrillation or atrial flutter, i.e. a past history
 of atrial fibrillation/flutter or atrial fibrillation/flutter detected on ECG, Holter,
 or telemetry following the index stroke/TIA event (a remote history of transient
 perioperative atrial fibrillation is not exclusionary

 2. Exclusively retinal stroke or TIA event.

 3. A most responsible etiological diagnosis for the qualifying stroke/TIA event has
 already been determined, i.e. probable small-vessel (lacunar) disease, probable large
 vessel disease, cervicocephalic artery dissection, venous sinus thrombosis,
 hypercoagulable states, or other known cause.

 4. Planned carotid endarterectomy within 90 days.

 5. Patient is already currently participating in a clinical trial involving an
 investigational medication or device.*

 6. Any finding on echocardiography for which there is already an evidence-based
 indication for long-term anticoagulation (e.g. mechanical heart valve, thrombus,
 etc.).

 7. Endocarditis

 8. Pacemaker or ICD device.

 9. Patients with known skin reactions to synthetic polymers or to silver. (Some people
 who display sensitivity to silver jewellery are sensitive to the impurities present in
 silver alloys and not to the silver itself. These people may participate.)