A Novel Staged Revascularization Strategy for Bilateral Severe Internal Carotid Artery Stenosis at High Risk for Hyperperfusion Syndrome.

Objective: Since bilateral severe internal carotid artery stenosis often is associated with severely decreased cerebrovascular reactivity (CVR) due to poor collateral blood flow, revascularization carries a high risk for development of hyperperfusion syndrome. In this study, we report a new staged strategy to prevent postoperative hyperperfusion syndrome in such patients.

Methods: Bilateral severe cervical internal carotid artery stenosis patients with decreased CVR to 10% or less on one side were prospectively enrolled in this study. We first performed carotid artery stenting on the side with the milder CVR decrease (lower-risk side), aiming to improve hemodynamics associated with the severe CVR decrease on the greater-risk side. Then, carotid endarterectomy or carotid artery stenting was performed on the contralateral side after an interval of 4-8 weeks.

Results: In all 3 cases enrolled in this study, CVR on the greater-risk side improved to 10% or more 1 month after the first treatment. The ratio of regional cerebral blood flow on the contralateral greater-risk side was 114% 1 day after the second treatment, and HPS did not develop in any of the cases.

Conclusions: Our treatment strategy, in which revascularization on the lower-risk side precedes that on the greater-risk side, is effective for the prevention of HPS in bilateral ICA stenosis patients.