Cerebrovascular reactivity before and after carotid endarterectomy

BACKGROUND The hemodynamic relevance of internal carotid artery (ICA) steno sis often does not correlate with anatomic features, as angiographically de fined. The cerebrovascular reactivity (CVR) has been advocated as a means o f defining the cerebral hemodynamic impairment. METHODS We assessed the results of pre- and postoperative CVR evaluation, u sing the CO, transcranial doppler method, in 25 patients with high-grade IC A stenosis. The patients with history of stroke, evidence of cerebral CT in farction or symptoms from the contralateral circulation or the brain stem w ere excluded to avoid the effects of cerebral infarction on the hemodynamic studies. Statistical analysis was used to evaluate the CVR changes after c arotid endarterectomy. RESULTS Preoperative evaluation showed that CVR was generally well correlat ed with the degree of ICA stenosis and concomitant contralateral carotid st eno-occlusion, Before endarterectomy the mean CVR value was 66.5% (moderate ly reduced). After surgery the overall mean value of CVR was 84.1% (normal) , with a statistically significant improvement. CONCLUSION The results of this study suggest that the CVR evaluation allows one to obtain hemodynamic information of clinical interest in the patients with ICA stenosis and that carotid endarterectomy is effective to restore the CVR in patients with cerebral hemodynamic impairment. (C) 1999 by Elsev ier Science Inc.