Is Impaired Cerebral Vasomotor Reactivity a Predictive Factor of Stroke in Asymptomatic Patients

Background and Purpose Identification of the subgroup of asymptomatic patients with severe internal carotid artery stenosis and high risk of stroke has important clinical implications. Cerebral vasomotor reactivity provides information regarding intracranial hemodynamic features and might have a prognostic value in predicting cerebrovascular ischemic events, especially in patients with carotid stenosis. The aim of our study was to assess the cerebral vasomotor reactivity in asymptomatic patients with carotid stenosis and evaluate its role in stroke occurrence. Methods Cerebral vasomotor reactivity was assessed using transcranial Doppler ultrasonology and the Diamox test (intravenous administration of 1.0 g acetazolamide) in 44 asymptomatic patients with severe (>70%) internal carotid artery stenosis. Patients were followed up prospectively (mean, 2 years). Results Cerebral vasomotor reactivity was estimated as good (>40% increase of blood flow velocity in the middle cerebral artery ipsilateral to the caro...