Background
Atrial fibrillation (AF) is a well-established cause of ischaemic stroke (IS), yet paroxysmal AF (pAF) often remains undetected during routine inpatient monitoring. The use of an external telemetry device (ETD) to detect AF is a key investigation following an Embolic Stroke of Undetermined Source (ESUS).
Aim
To evaluate the detection rate of AF using an external telemetry device in ESUS patients.
Method
A single centre, retrospective cohort study of patients fitted with an ETD for 29 days after a confirmed ischaemic stroke of ESUS aetiology between January 2023 and December 2024. Patients excluded from the study were those without or unable to use a smart phone.
Results
229/ 621 (37%) IS patients met diagnostic criteria for ESUS. 95/229 (41%) ESUS patients met the inclusion criteria for ETD monitoring. The median age was 69yrs; 64% female. The ETD was applied on median of 4 days after stroke ictus and worn for a median of 29 days.
pAF or atrial flutter was detected in 3/95 ESUS patients (3%) with detection at day 1, 10 and 15 respectively. Median age of AF detection was 70 years. Other cardiac abnormalities were detected in 5 patients (5%) including heart block and supraventricular tachycardia.
Conclusion
59% of ESUS patients were unable to use an ETD. 29 days of ETD monitoring is associated with a low rate of pAF detection in ESUS patients able to use a smart phone. Implantable cardiac loop recorders may be more applicable and yield greater diagnosis of pAF in ESUS.