The effect of diagnostic hypercapnic cerebrovascular reactivity imaging on vital signs and acute and follow-up ischemic adverse events in patients with flow-limiting intracranial arterial stenosis.

Background And Purpose: Anatomical imaging is a hallmark for visualizing chronic and acute infarcts but provides incomplete information on stroke risk. Respiratory hypercapnic gas challenges show promise for non-invasively assessing hemodynamic function and mapping cerebrovascular reserve capacity, an indicator of how near parenchyma is to exhausting autoregulatory capacity. However, limited safety information exists for this method in high-risk patients with flow-limiting stenosis.