Stroke from carotid endarterectomy: When and how to reduce perioperative stroke rate?

Objectives: to analyse four years of CEA with respect to the underlying mec hanisms of perioperative stroke and the role of intraoperative monitoring i n the prevention of stroke. Patients and Methods: from January 1996 through December 1999, 599 CEAs wer e performed in 404 men and 195 women (mean age: 65 years, range: 39-88). Al l operations were performed under general anaesthesia using computerised el ectroencephalography (EEG) and transcranial Doppler (TCD). Any new or any e xtension of an existing focal cerebral deficit, as well as stroke-related d eath were registered. Perioperative strokes were classified by time of onse t (intraoperative or postoperative), outcome (minor or major stroke), and s ide (ipsilateral or contralateral). Stroke aetiology was assessed intraoper atively by means of EEG, TCD, completion arteriography or immediate re-expl oration, and postoperatively by duplex sonography, computerised tomography (CT) or magnetic resonance imaging (MRI) of the head. Results: perioperative stroke or death occurred in 20 (3.3%) patients. In f our operations stroke was apparent immediately after surgery. Mechanisms of these strokes were ipsilateral carotid artery occlusion (1) and embolisati on (3). In 16 patients stroke developed after a symptom-free interval (2-72 h, mean 18 h) due to occlusion of the internal carotid artery on the hyper perfusion syndrome (1), intracerebral haemorrhage (1), and contralateral is chaemia due to prolonged clamping (1). In three procedures the cause was un known. Conclusions: in our experience most strokes from CEA developed after a symp tom-free interval and mainly due to thromboembolism of the operated artery. We suggest the introduction of additional TCD monitoring during the immedi ate postoperative phase.