A Case of Post-Carotid Endarterectomy Hyperperfusion Syndrome

ABSTRACT

Most neurologic complications after carotid endarterectomy (CEA) are ischemic in nature, either embolic or thrombotic. However brain edema can also cause neurologic dysfunction that may be related to hyperperfusion secondary to failure of vascular autoregulation. In Korea there has been no report on hyperperfusion syndrome following CEA. We report the first case of hyperperfusion syndrome in 70 cases of CEA series (1.43%) since November 1994. The patient presented with headache and seizures associated with marked unilateral cerebral hemispheric edema on the sixth post-CEA day. Imaging studies included CT, MRI, MRA, carotid duplex, TCD and SPECT. The possible risk factors for developing hyperperfusion syndrome in this patient included high-grade stenosis, poor collateral flow, evidence of chronic ipsilateral hypoperfusion, development of immediate post-CEA hypertension, and post-CEA increment of internal carotid artery blood flow velocity to 190% of the pre-CEA level on follow-up TCD. Cerebral hyperperfusion syndrome is a rare but significant complication of CEA that may be reversible. Hyperperfusion syndrome should be questioned if the patient develops a new neurological problem after CEA.