Differences in Stroke Recurrence Risk Between Atrial Fibrillation Detected on ECG and 14-Day Cardiac Monitoring.

Area of Science:

• Cardiology
• Neurology
• Stroke Medicine

Background:

• Standard stroke investigations include ECG and prolonged cardiac monitoring (PCM) for atrial fibrillation (AF).
• AF after stroke is often treated as a single entity, irrespective of detection method.
• This study investigates if AF detection method impacts stroke recurrence risk.

Purpose of the Study:

• To compare the risk of recurrent ischemic stroke in patients with ECG-detected AF versus PCM-detected AF.
• To evaluate the association between AF detection method and stroke recurrence.
• To inform stroke management strategies based on AF detection.

Main Methods:

• Retrospective cohort study using the London Ontario Stroke Registry (2018-2020).
• Included patients with ischemic stroke/TIA and ECG- or PCM-detected AF (≥30 seconds).
• Used Cox proportional hazards models to assess recurrent ischemic stroke risk, adjusting for key clinical factors.

Main Results:

• 16 recurrent strokes in ECG-AF group vs. 2 in PCM-AF group.
• Recurrent stroke rates: 4.05/100 patient-years (ECG-AF) vs. 0.72/100 patient-years (PCM-AF).
• ECG-detected AF showed a 5-fold higher adjusted risk of recurrent stroke (aHR 5.06, P=0.034).

Conclusions:

• ECG-detected AF is associated with a substantially higher risk of recurrent ischemic stroke.
• This difference persists even with high anticoagulation rates (>80%).
• Stroke management may need to consider the method of AF detection to stratify recurrence risk.