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Introduction: Hypoperfusion symptoms, defined as symptoms related to change in position (i.e. supine to seated), effort or exertion, or recent change in antihypertensive medication have been used in stroke studies as a surrogate for detecting hemodynamic compromise. However, the validity of these symptoms in identifying flow compromise in patients has not been well established. We examined whether hypoperfusion symptoms correlated with quantitative evaluation of flow compromise in the prospective observational Vertebrobasilar Flow Evaluation and Risk of Transient Ischemic Attack and Stroke (VERiTAS) study.Methods: VERiTAS enrolled patients with recent vertebrobasilar TIA or stroke and ≥50% atherosclerotic stenosis or occlusion in vertebral and/or basilar arteries. Hemodynamic status using large vessel flow in the vertebrobasilar territory was measured using quantitative magnetic resonance angiography (QMRA), and patients were designated as low, borderline or normal flow based on distal territory regional flow, incorporating collateral capacity, as previously reported. The presence of qualifying event hypoperfusion symptoms was assessed relative to the quantitatively determined flow status (normal vs borderline/low), and also examined as a predictor of subsequent stroke risk.Results: Of the 72 enrolled subjects, 66 had data on hypoperfusion symptoms available. On initial QMRA designation, 43 subjects were designated as normal flow vs. 23 subjects designated as low flow (n=16) or borderline (n=7). Of these, 5 (11.6%) normal flow and 3 (13.0%) low/borderline flow subjects reported at least one qualifying event hypoperfusion symptom (p=0.99, Fisher’s exact test). Hypoperfusion symptoms had a positive predictive value of 37.5% and negative predictive value of 65.5% for low/borderline flow status. Compared to flow status, which strongly predicted subsequent stroke risk, hypoperfusion symptoms were not associated with stroke outcome (p=0.87, log rank test).Conclusions: These results suggest that hypoperfusion symptoms alone correlate poorly with actual hemodynamic compromise, and subsequent stroke risk in vertebrobasilar disease, and are not a reliable surrogate for flow measurement.