B Kleiser1, B Widder. 1. Department of Neurology, University of Ulm, FRG.
Abstract
BACKGROUND AND PURPOSE: Retrospective studies have found a close correlation between an impaired cerebrovascular reserve capacity and the incidence of hemodynamic stroke. The present study evaluates this relation prospectively. METHODS: We measured the CO2 reactivity in 85 patients with internal carotid artery occlusions by transcranial Doppler sonography (Doppler CO2 test). All patients were prospectively followed for 38 +/- 15 (mean +/- SD) months. RESULTS: In the group with sufficient CO2 reactivity, four of 48 (8%) developed ipsilateral transient symptoms, none a stroke. In cases with diminished or exhausted cerebrovascular reserve capacity, 12 of 37 (32%) suffered an ipsilateral event (four transient ischemic attacks, eight strokes) (p less than 0.01). CONCLUSIONS: The Doppler CO2 test seems to be a valuable method of estimating the risk of stroke in patients with carotid artery occlusions.
BACKGROUND AND PURPOSE: Retrospective studies have found a close correlation between an impaired cerebrovascular reserve capacity and the incidence of hemodynamic stroke. The present study evaluates this relation prospectively. METHODS: We measured the CO2 reactivity in 85 patients with internal carotid artery occlusions by transcranial Doppler sonography (Doppler CO2 test). All patients were prospectively followed for 38 +/- 15 (mean +/- SD) months. RESULTS: In the group with sufficient CO2 reactivity, four of 48 (8%) developed ipsilateral transient symptoms, none a stroke. In cases with diminished or exhausted cerebrovascular reserve capacity, 12 of 37 (32%) suffered an ipsilateral event (four transient ischemic attacks, eight strokes) (p less than 0.01). CONCLUSIONS: The Doppler CO2 test seems to be a valuable method of estimating the risk of stroke in patients with carotid artery occlusions.