Shaking Out Stroke Mimics

In a world of continued aggressive guideline- and pharmaceutical-sponsored expansion of stroke treatment with thrombolytics, this article fills and important need – better codifying the predictors of stroke mimics. While other editorials espouse the need to be fast without being sure, this is frankly irresponsible medicine – and, in resource-constrained environments, unsustainable.

These authors at two academic centers performed a retrospective clinical and imaging review of 784 patients evaluated for potential acute cerebral ischemia. Patients were excluded if they had signs of acute stroke on initial non-contrast imaging, and if they did not subsequently undergo MRI. Based on review of the totality of clinical information for each patient, 41% of this cohort were deemed stroke mimics. The authors scoring system, then derived 6 variables – and 3 or more were present, the chance of stroke mimic being cause of the current presentation was 87.2%. Their criteria:

  • Absence of facial droop
  • Age <50 y/o
  • Absence of atrial fibrillation
  • SBP <150 mm Hg
  • Presence of isolated sensory deficit
  • History of seizure disorder

When the rate of tPA administration to stroke mimics is ~15%, and 30-40% of patients evaluated for stroke are stroke mimics – there is a lot of waste and potential harm occurring here. These authors suggest the use of this score could potentially halve these errant administrations for 94% sensitivity, or cut errant administrations down to 2% with 90% sensitivity. Considering the patients for which stroke/stroke mimic is an ambiguous diagnosis, it is reasonably likely the symptoms are of lesser severity – and in the range for which tPA is of most tenuously “proven” value. While their rule has not been prospectively validated, some of these elements certainly have face validity, and can be incorporated into current practice at least as a reminder.

“FABS: An Intuitive Tool for Screening of Stroke Mimics in the Emergency Department”