Smartwatches for Detection of Atrial Fibrillation (AFib) in Secondary Prevention of Cryptogenic Stroke - WATCH AFib A Prospective, Intraindividual-controlled, Multicenter Clinical Study
Background: In secondary prevention of ischemic stroke, detection of atrial fibrillation (AFib) and subsequent anticoagulation therapy reduce the risk of recurrent stroke by approximately 60%. Prolonged electrocardiogram (ECG) monitoring up to 6 months significantly increases detection of AFib in cryptogenic stroke. Wearables like smartwatches have recently been shown to adequately detect AFib in the general population. Thus, prolonged ECG monitoring after cryptogenic ischemic stroke or transient ischemic attack (TIA) using a smartwatch could lead to a reduction of recurrent stroke by prompting adequate anticoagulation therapy and may constitute a cost-effective, non-invasive, and broadly-available alternative to the current standard of care. Hypothesis: The investigators hypothesize that AFib detection via smartwatch in patients with cryptogenic TIA or ischemic stroke is accurate compared to an implantable event recorder.
Methods: The investigators introduce a prospective, intraindividual-controlled, multicentre clinical study in patients with cryptogenic ischemic stroke or TIA. In addition to an implanted event recorder as indicated by clinical standard, included patients receive a smartwatch for detection of AFib. ECG-data from smartwatches will be continuously monitored by two independent cardiologists. As soon as AFib is confirmed, a doctoral appointment is set to evaluate start of anticoagulation. The follow-up period will be six months. The study consists of four study visits: a baseline visit, two phone visits at one and three months, and an end of trial visit at six months. Primary
Objective: To compare smartwatch and event recorder based analysis for sensitivity and specificity of AFib detection per patient after six months
• Implanted Event Recorder with telemedicinal function (e.g., Biotronik BioMon 3m ProMRI HomeMon or similar)
• Cryptogenic stroke (within the last six month) after full standard evaluation:
‣ Stroke detected by computed tomography (CT) or magnetic resonance imaging (MRI) that is not lacunar (lacunar is defined as a subcortical infarct in the distribution of the small, penetrating cerebral arteries whose largest dimension is ≤1.5 cm on CT or ≤2.0 cm on MRI diffusion images)
⁃ Absence of extracranial or intracranial atherosclerosis causing ≥50 percent luminal stenosis of the artery supplying the area of ischemia
⁃ No major-risk cardioembolic source of embolism (i.e., no permanent or paroxysmal atrial fibrillation, sustained atrial flutter, intracardiac thrombus, prosthetic cardiac valve, atrial myxoma or other cardiac tumors, high-grade mitral valve stenosis, recent (within four weeks) myocardial infarction, left ventricular ejection fraction \<30 percent, valvular vegetations, or infective endocarditis)
⁃ No other specific cause of stroke identified (e.g., arteritis, dissection, migraine, vasospasm, drug abuse)
⁃ No paroxysmal atrial fibrillation in 72h of in-hospital ECG-monitoring, including at least one Holter- ECG for 24 hours.
• Cryptogenic TIA with definite cortical syndrome (aphasia, neglect or homonymous hemianopia) (within the last six month) after full standard evaluation (see above)
• Age: ≥40 yrs.
• At least one of the following risk factors:
‣ CHA2DS2VASc score ≥4
⁃ Atrial runs
⁃ Left atrial size \> 45mm
⁃ Left atrial appendage flow ≤ 0.2m/s
• No contraindication for anticoagulant therapy after acute phase of stroke
• Written informed consent by patient or authorized caregiver