Embolic Stroke of Undetermined Source in Saudi Arabia: Prevalence, Patient Characteristics, and Outcomes

Background: Embolic stroke of undetermined source (ESUS) is a newly introduced clinical construct to better characterize cryptogenic stroke. It is associated with considerable morbidity and mortality and a high recurrence rate. It has not previously been investigated in Saudi stroke patients. We aimed to conduct a descriptive analysis of ESUS in Saudi Arabia, including its frequency among patients with acute stroke, characteristics, and outcomes. Methods: We reviewed all ischemic stroke patients admitted to the stroke unit at King Abdulaziz Medical City-Riyadh, Saudi Arabia, from February 2016 to July 2018. We applied the criteria proposed by the Cryptogenic Stroke/ESUS International Working Group, which defines ESUS as a radiologically confirmed nonlacunar brain infarct without (a) extracranial or intracranial atherosclerosis causing ≥50% stenosis in arteries supplying the ischemic area, (b) a major-risk cardioembolic source, (c) any other specific cause of stroke. We compared ESUS patients with the other stroke patients. Study was approved by local institutional review board. Results: Of the 736 patients admitted with ischemic stroke, 147 (20%) had ESUS. Patients with ESUS had fewer vascular risk factors compared to patients without ESUS. Nearly third were either dead or dependent at discharge. There were no significant differences between ESUS and other types of ischemic strokes in mortality rate and independence at discharge. Conclusion: ESUS is common in Saudi stroke patients. Despite of the lack of definite etiology, it is associated with considerable morbidity and mortality.