Subclinical Atrial Fibrillation Is Common in Patients with Cryptogenic Stroke

One third of ischemic strokes remain cryptogenic even after thorough inpatient evaluation. Numerous studies suggest that some of these patients may have paroxysmal atrial fibrillation (AF) that remains undiagnosed during their stroke hospitalization. Failing to detect these cases of AF may result in suboptimal antithrombotic therapy. However, what type and duration of cardiac monitoring should be used to rule out subclinical AF remain unclear.

To address this question, investigators placed implantable loop recorders (ILRs) in 51 patients who had received standard stroke evaluations, including vascular imaging, echocardiography (transthoracic in all patients and transesophageal in 30), and at least 24 hours of Holter monitoring without eviden…