Isolated Subarachnoidal Hemorrhage following Carotid Endarterectomy

Cerebral hyperperfusion syndrome is a rare but well-described complication following carotid endarterectomy or stenting. Clinical signs are ipsilateral, throbbing, unilateral headache with nausea or vomiting, seizures, and neurological deficits, with or without intracerebral abnormalities on CT scan, such as brain edema or intracerebral hemorrhage. Subarachnoidal hemorrhage is rarely described especially if it occurs isolated. We describe a 74-year-old man with a history of high blood pressure, hypercholesterolemia, atrioventricular block with pacemaker, and ischemic cardiopathy with coronary bypass. He underwent right carotid endarterectomy for a 90% NASCET asymptomatic stenosis. Four days after surgery, he complained of unusual headaches with right, throbbing hemicrania. Nine days after surgery, he presented with left hemiplegia and a partial motor seizure. He had fluctuant altered consciousness, left hemiplegia, and left visual and sensory neglect. Brain CT showed right frontal subarachnoidal hemorrhage without parenchymal bleeding. Cerebral angiography found no cerebral aneurysm, no vascular malformation, but a vasospasm of the left middle cerebral artery. Transcranial Doppler confirmed this vasospasm. Evolution was favorable with no recurrence of seizures but with an improvement of the neurological deficits and vasospasm. Physicians should bear in mind this very rare complication of endarterectomy and immediately perform neuroimaging in case of unusual headache following endarterectomy or angioplasty.