Carotid Endarterectomy - Procedure

Procedure

The internal, common and external carotid arteries are clamped, the lumen of the internal carotid artery is opened, and the atheromatous plaque substance removed. The artery is closed, hemostasis achieved, and the overlying layers closed. Many surgeons lay a temporary shunt to ensure blood supply to the brain during the procedure. The procedure may be performed under general or local anaesthesia. The latter allows for direct monitoring of neurological status by intra-operative verbal contact and testing of grip strength. With general anaesthesia indirect methods of assessing cerebral perfusion must be used, such as electroencephalography (EEG), transcranial doppler analysis and carotid artery stump pressure monitoring. At present there is no good evidence to show any major difference in outcome between local and general anaesthesia.

Minimally invasive procedures have been developed, by threading catheters through the femoral artery, up through the aorta, then inflating a balloon to dilate the carotid artery, with a wire-mesh stent and a device to protect the brain from embolization of plaque material. The FDA has approved 7 carotid stent systems as safe and effective in patients at increased risk of complications for carotid surgery and 1 carotid stent system for patients at average or usual risk of carotid surgery. The SAPPHIRE study of patients at high surgical risk for carotid surgery demonstrated non-inferiority for carotid stenting compared to carotid surgery. The CREST trial, the largest trial comparing carotid surgery to carotid stenting in over 2,500 patients found that carotid artery stenting resulted in a stroke rate of 6.4% versus 4.7% for endarterectomy at 4 years. However, carotid endarterectomy was associated with a slightly higher rate of myocardial infarction around the time of the procedure (2.3% versus 1.1%). Although the study's composite index including death, stroke, and myocardial infarction is not significantly different between the two groups, myocardial infarction was associated with less impact on quality of life as compared with stroke at one year.

It is the consensus of experts in the field that carotid artery stenting should be considered an option for high risk patients who require carotid artery revascularization to prevent stroke.