RESULTS OF ISOLATED CAROTID SURGERY IN PATIENTS WITH VERTEBROBASILAR INSUFFICIENCY

The purpose of this study was to establish whether carotid-revasculari zed patients who had preoperative vertebrobasilar insufficiency (VBI) displayed distinctive characteristics and whether a particular prognos is would ensure. From January 1985 to December 1993, 1022 carotid reva scularizations were performed, of which 114 (11%) were for high-grade stenosis associated with VBI. The group with VBI and the group without VBI were compared according to a set of 121 prospectively collected v ariables. Of all the demographic and risk-factor variables, only femal e prevalence (42% vs. 27%) and hypertension (77% vs. 27%) distinguishe d the group with VBI, who also exhibited a significantly higher propor tion of significant contralateral carotid lesions (27.2% vs. 8.9%) and vertebrosubclavian lesions (38.6% vs. 24.8%). Following isolated caro tid surgery, there was no statistically significant difference between the two groups as to their cumulative rate of permanent neurological mortality and morbidity (2.6% in the group with VBI vs. 3.4% in the gr oup without it). With an average follow-up of 60 months, VBI was cured in 82.4% and improved condition shown in 6.5% of patients. However, t he proportion of good results fell to 65% in patients with a nonfuncti onal circle of Willis. Out of 13 cases of failure to control VBI, cure was finally effected by means of contralateral revascularization in 3 cases and by means of vertebrosubclavian revascularization in 5 cases out of 6. At 5 years, the actuarial rates of neurological event-free intervals and survival were not different from one group to another. I n most cases, isolated carotid surgery is sufficient to bring vertebro basilar insufficiency under control, except when significant vertebros ubclavian lesions and a nonpatent circle of Willis call for simultaneo us carotid and vertebral artery surgery.