To describe the incidence and characteristics of acute ischemic stroke in cardiac arrest patients.

Brain injury is the leading cause of death and disability post-cardiac arrest, and hypoxic-ischemic brain injury (HIBI) severity is associated with poor outcomes. There is limited information about the co-occurrence of acute ischemic stroke and its impact on outcome.

We performed a structured MRI review of a retrospective multicenter cohort of cardiac arrest patients. We included MRIs performed within 7 days from arrest and excluded traumatic brain injury, intracranial hemorrhage, and ischemic stroke at admission. Univariate and multivariable analyses were performed to explore the characteristics of cerebral infarctions and their association with poor outcomes (i.e., Cerebral Performance Category of 3-5).

Among 351 included patients, 107 had cerebral infarction based on MRI (30.5%). The most common pattern of stroke is multifocal small embolic (61.7%), followed by punctate (28.9%), watershed (7.48%), territorial (6.5%), and lacunar (2.8%). The patients with acute ischemic stroke are older (p<0.01). Chronic white matter disease was associated with the occurrence of acute ischemic stroke (odds ratio [OR] 1.89 [1.11-3.25], P<0.05). In univariate and multivariable analysis, the presence of acute ischemic stroke is not associated with poor outcomes. Worse outcome is associated with older age (OR 1.05 [1.02-1.08], P<0.001) and presence of HIBI (OR 4.37 [1.9-10.5], P<0.001).

Acute ischemic stroke is common after cardiac arrest. Acute infarctions after arrest are associated with chronic white matter disease. The most common pattern is multifocal embolic, possibly due to cardioembolism and hypercoagulable state. The impact of cerebral infarctions on cardiac arrest survivors requires deeper investigation in future longitudinal studies.