Focal motor seizures complicating carotid endarterectomy.

We studied four patients with focal motor seizures complicating carotid endarterectomy and compared them with 14 other cases reported previously. Seventeen of the 18 patients had high-grade carotid stenoses. A severe unilateral headache usually preceded seizure activity, which was followed by prolonged Todd's paralysis. Eight patients had histories of ipsilateral stroke. There was no association with perioperative hypertension. Two patients who were receiving heparin sodium had intracerebral hemorrhages that caused one of the two postoperative deaths. The patency of all endarterectomized carotid arteries was recorded by arteriography or noninvasive studies. These data suggest that patients who have severe unilateral headaches following ipsilateral carotid endarterectomy for high-grade stenoses are at risk for focal motor seizures. The roles of antithrombotic agents and anti-seizure medication in this setting are unclear.