Time is brain: Balancing risk in the treatment of presumed cardioembolic stroke.

Objective: To assess whether clinical criteria can differentiate between presumed embolic strokes and non-embolic strokes before the full etiologic workup.

Methods: Between January 1, 2014 to December 30, 2015, patients with a diagnosis of stroke or transient ischemic attack were first classified clinically (without access to a cardiac assessment) as: 1. presumed embolic stroke defined as a combination of definite cardioembolic stroke and likely to be embolic stroke (no evidence of large/small artery atherosclerosis); 2. non-embolic strokes; i.e. small/large artery diseases and stroke due to other causes. Stroke etiology was reassessed after investigations and concordances between the early diagnosis and final classifications were analyzed.

Results: 77 patients with early diagnosis of presumed embolic strokes and 45 cases with non-embolic stroke (selected randomly) were enrolled. We were able to differentiate between presumed embolic strokes and non-embolic strokes with a high level of accuracy (sensitivity 81.40%, 95% CI: 71.55%-88.98%; specificity 80.56%, 95% CI: 63.98%-91.81%). A moderate level of agreement between initial and final diagnosis of embolic/non-embolic strokes (kappa 0.58, SE 0.08, p≤0.01) was observed. The results of carotid imaging improved the specificity and positive likelihood ratio of correct differentiation.

Conclusions: Those at high risk of embolism can be diagnosed clinically even before the completion of tests. This is a practical approach to distinguish patients at risk and help balance early risks of recurrence with those of short-term anticoagulation.