Etiologies of simultaneous cerebral infarcts in multiple arterial territories: A simple literature-based pooled analysis

Introduction: Acute multiple infarcts in multiple cerebral circulations are thought to suggest the presence of cardioembolic sources. However, several studies have shown other etiologies for simultaneous cerebral infarcts in multiple arterial territories. Methods: We conducted a systematic review of the literature using PubMed, Scopus, Embase, Clinicaltrial.gov, WHO International Clinical Trials Registry Platform (ICTRP), and Cochrane library. Studies reporting multiple acute strokes in more than one arterial territory based on diffusion-weighted imaging (DWI) findings were reviewed and included. Studies were excluded if they had limited inclusion criteria, performed limited subgroup analysis, did not use diffusion weighted imaging (DWI), and were not published in English. Results: Out of 15056 stroke patients from 21 studies included in this study, 1914 (13%) patients had acute multiple infarcts in multiple cerebral circulations. One hundred and ninety-nine patients were excluded as their workup and diagnosis were not reported. Out of 1715 patients, 472 (27.6%) patients had an undetermined etiology. Cardioembolism was the most common cause of stroke in multiple arterial territories [37.2%, 95% confidence interval (CI): 36-40%] followed by large artery atherosclerosis including aortic arch atheroma (25.7%, 95% CI: 21-25%). Hematological disorders were found to be the cause of cerebral infarcts in 36 (2.1%, 95% CI: 2-4%) patients. Other etiologies for stroke in multiple arterial territories were small vessel pathologies and intracranial small vessel atherosclerosis (1.8%), inflammatory disorders such as vasculitis and infection (0.2%), and iatrogenic causes (0.1%). Conclusion: Acute multiple infarcts in multiple cerebral circulations occur among 13% of stroke patients. Although cardioembolism is the most common cause, there are several other etiologies that require a different workup and secondary prevention strategy.