Ischemic Stroke Due To Acute Basilar Artery Occlusion: Proportion And Outcomes

Background Multiple case series, mostly highly selected, have demonstrated a very high mortality following acute basilar artery occlusion The more widespread availability and use of non invasive vascular imaging over recent years has increased the rate of ABAO diagnosisObjectives To estimate the proportion of diagnosed ABAO among all cause ischemic stroke in an era of increasing use of non invasive vascular imaging and to compare the characteristics and outcomes between these two groupsMethods We compared 27 consecutive cases of ABAO identified in a university hospital between 2003 and 2007 with 311 unselected cases of ischemic stroke from two 4 month surveysResults ABAO diagnosis increased from 0 3% of all cause ischemic stroke (2003-2004) to 1 1% (2007), reflecting the increased use of non invasive vascular imaging In comparison to all cause ischemic stroke, ABAO patients were younger (mean age 60 vs 71 years), were more likely to be male (89% vs 60%), had less atrial fibrillation (7% vs 26%), more severe strokes (baseline NIHSS over 20 52% vs 12%), higher admission white cell count (12,000 vs 9000 cells/mm(3)), lower admission systolic blood pressure (140 +/- 24 vs 153 +/- 27 mmHg), higher in hospital mortality rates (30% vs 8%) and worse functional outcome (modified Rankin scale <= 3, 22% vs 56%) (P < 0 05 for all) Rates of reperfusion therapy for ABAO increased from 0 in 2003-2004 to 60% in 2007Conclusions In this study, ABAO patients represented approximately 1% of all cause ischemic stroke and were about a decade younger than patients with all cause ischemic stroke We report a lower ABAO mortality compared to previous more selected case series, however, most survivors had a poor functional outcome Given the marked clinical heterogeneity of ABAO, a low threshold for non invasive vascular imaging with a view to definitive reperfusion treatment is needed IMAJ2010, 12 671-675