Introduction: Embolic stroke of undetermined source (ESUS) describes a stroke for which no cause has been found, which implicates embolism as a cause of stroke. There are several mechanisms of cryptogenic ischemic stroke including a covert structural cardiac lesion, paroxysmal atrial fibrillation (AF), hypercoagulable state or undiagnosed malignancy. As ESUS is associated with a significant stroke recurrence, a clear risk prediction and management is of utmost importance to improve prognosis. In ESUS, the options for further investigation include long-term cardiac monitoring, transesophageal echocardiography, investigation for occult malignancy or arterial hypercoagulability. Implantable cardiac monitors offer the capability to maximize the chances to detect AF and should be considered after non-invasive monitoring in patients with previous stroke at higher probability of having AF. Current guidelines do not suggest a specified approach (ie, blood, echocardiographic, ECG or brain imaging biomarkers) to screen AF in ESUS patients.
Methods: We enrolled consecutive patients with ESUS admitted to our Stroke Unit from January 2021 to October 2022.
Results: In the study period, 509 patients with acute ischemic stroke were admitted in our Stroke Unit. ESUS was diagnosed in 10.6% of patients (54/509). Only 12 of these patients underwent loop recorder implantation (mean age 76.5 y, 75% male), according to clinician judgment. AF was detected in 16.6% of these patients (2/12).
Conclusions: AF is one of the causes of ESUS; a recognition of AF in these patients is important, because its treatment can modify the risk of recurrence. A tailored diagnostic pathway, including clinical and echocardiographic parameters, is advisable to improve the recognition of this arrhythmia in ESUS patients.