Abstract
Background Undocumented atrial fibrillation (AF) is suspected as a main stroke cause in patients
with embolic stroke of undetermined source (ESUS), but its prevalence is largely unknown.
This prospective study therefore aimed at delineating the prevalence of AF in patients
with ESUS using continuous cardiac monitoring by implantable loop recorder (ILR) with
daily remote interrogation over a period of 3 years and its clinical consequences,
including recurrent stroke.
Methods In consecutive patients with an ESUS diagnosis after complete work-up, an ILR was
implanted and followed by daily remote monitoring until AF was detected or a follow-up
of at least 3 years was completed. Additionally, the ILR was interrogated in-hospital
in 6-month intervals.
Results A total of 123 patients (74 male, mean age 65 ± 9 years) were enrolled and completed
the 3 years study period. AF was detected in 51 patients (41.4%). In 43 of the 51
AF positive patients (84%) oral anticoagulation was established. Recurrent strokes
occurred in 18 patients (14.6%) of this ESUS population, 9 of these patients being
AF positive (17.6% of the AF-positive patients) and 9 being AF negative (12.5% of
AF-negative patients). Patients with AF were slightly older than patients without
AF (63.1 ± 8.8 vs. 67.5 ± 9.6 years, p = 0.12). Other parameters such as CHA2DS2-VASc score, infarct localization, micro- and macroangiopathy, carotid or aortic plaques,
or stroke recurrence were not significantly different between groups.
Conclusion In ESUS patients, early implantation of an ILR with cardiac monitoring and remote
transmission over a 3-year period detected AF in 41.4% and resulted in oral anticoagulation
in 84% of these patients.
Keywords
atrial fibrillation - embolic stroke of undetermined source - implantable loop-recorder
- remote monitoring - stroke
