Abstract W P400: Headache at the Onset of Anterior versus Posterior Circulation Ischemic Stroke
Background: Past evidence suggests that there is a higher incidence of onset headache with posterior rather than anterior circulation stroke. We sought to further explore this connection in order to better understand the mechanisms underlying onset headache and to examine this symptom in relation to ischemic stroke.
Methods: A retrospective chart review was conducted of 253 patients who presented to Vanderbilt University Medical Center in 2013 with ischemic stroke in either the anterior or posterior circulation. The significant difference between the incidence of onset headache in the anterior and posterior circulation territories was analyzed using a chi-squared test of independence. The frequency of onset headache was compared between the two groups, as well as between more specific locations within the posterior circulation and the middle cerebral artery (MCA).
Results: A total of 48 (19%) of patients reported experiencing onset headache. Of those, 12 (25%) suffered a stroke in the anterior circulation, while 28 (58%) suffered a stroke in the posterior circulation (The remaining 8 were excluded due to multiple infarcts or poorly defined territories). Analysis was done comparing the MCA, the posterior cerebral artery (PCA), and the vertebrobasilar territories. The frequency of onset headache was 21% for vertebrobasilar stroke, 6.1% for MCA stroke, and 33% for PCA stroke. Compared to the other areas, PCA stroke showed a significantly higher rate of headache as a symptom at onset (χ2 = 18.60, p < 0.001, ϕc = 0.312). Furthermore, 20 (42%) of the 48 patients in this study who had reported onset headache were found to have suffered ischemia of the thalamus.
Conclusions: Patients who suffered a stroke in the PCA territory were more likely to have experienced a headache at stroke onset. Given the rich blood supply to the thalamus from the posterior circulation, an additional mechanism linking ischemic stroke in the PCA to thalamic pain pathways should be further scrutinized as a possible cause for onset headache.
Author Disclosures: C. Cahill: None. K. Espaillat: None. E. Gilchrist: None. M. Froehler: None.
- © 2015 by American Heart Association, Inc.