Background and purpose: Patients with acute ischemic stroke who undergo emergent cerebral angiography for consideration of intra-arterial treatment and do not have an angiographically demonstrable occlusion pose a management dilemma. The authors reviewed their experience to determine the clinical out comes of patients with ischemic stroke evaluated within 6 hours of symptom onset in whom negative angiograms were obtained.
Methods: A prospective registry was maintained for all patients (N = 56) who were considered for intra-arterial thrombolysis. Patients without angiographic arterial occlusion were not treated with thrombolytics, and data pertaining to clinical characteristics and neuroimaging findings was collected. Follow-up data were acquired through clinic visits or telephone interviews at 5.5 +/- 5.0 months (mean +/- SD), range 1 to 15 months, after onset of stroke.
Results: Of the 56 patients, no arterial occlusion was observed in 17 (30%) patients (mean age 65.8 +/- 13.0 years; 7 were men). The mean (+/- SD) baseline National Institute of Health stroke scale score was 10.2 +/- 7.1. Symptoms were referable to the anterior or posterior circulation in 76% and 18% of the patients, respectively; they could not be localized to either circulation in 6%. Follow-up neuroimaging studies demonstrated cerebral infarction in 12 of 14 patients. Eleven of the 17 had a favorable long-term recovery as assessed by the modified Rankin Scale (score 0 or 1). Five other patients had modified Rankin Scale scores of 3 (n = 1), 4 (n = 2), or 5 (n = 2). One patient died during the follow-up period. With regard to location of ischemic deficits, the highest rate of death or dependency was observed in patients with pontine infarction (three of four patients).
Conclusion: Although the outcome following ischemic stroke in patients without angiographically documented occlusion appears to be better than that reported for patients with angiographically documented occlusion, death or disability is observed in at least one third of the patients. There fore, acute ischemic stroke in the absence of angiographic occlusion is not entirely a "benign" entity and can be particularly devastating when the brainstem is involved.