Association Between CT With Angiography and 30-Day Risk of Stroke or Transient Ischemic Attack in a Canadian Emergency Department Setting.

INTRODUCTION

A subset of undifferentiated vertigo cases can be attributed to dangerous central causes such as posterior circulation ischemic stroke (PCIS) or transient ischemic attack (TIA). Due to a lack of validated clinical risk scoring tools, there is currently high heterogeneity in emergency department (ED) neuroimaging practices for patients presenting with undifferentiated vertigo. Therefore, this study assessed the utility of head and neck CT with angiography (CTA) for risk stratifying ED patients presenting with vertigo. The primary objective of this study was to compare 30-day stroke and TIA outcomes between ED vertigo patients who received CTA at their index visit versus those who did not. The impact of index visit CTA on secondary outcomes of interest was also measured, including ED length of stay (LOS), hospital LOS, and 30-day ED revisit rate.

METHODS

This retrospective study analyzed ED visit data across four tertiary care ED's over a one-year period. Adult patients presenting with a chief complaint of vertigo were eligible for study inclusion. Administrative data of the variables of interest was gathered from Canadian medical databases. Regression modeling was used to adjust for predetermined variables to evaluate the association between index visit CTA imaging, and stroke or TIA diagnosis at 30 days.

RESULTS

A 30-day diagnosis for stroke or TIA was found in 20.7% of the CTA group, and in 1.2% of the No CTA group. The odds ratio (OR) was 22.3 (95% confidence interval (CI): 15.03-33.02) unadjusted, and 18.3 (95% CI: 14.85-22.45) after adjustment. The CTA group had a longer average ED LOS (+114 minutes), a shorter average total hospital LOS within 30 days (-2.2 days), and a higher 30-day ED revisit rate when compared to the No CTA group (4.0% versus 1.5%).

CONCLUSIONS

Patients who received CTA at their index visit had 18.3 times greater odds of TIA or stroke diagnosis at 30-days, stayed longer in the ED, were more likely to revisit the ED within 30 days, and had a shorter mean hospital stay.