Carotid Endarctectomy and Stenting
The severity of carotid artery stenosis strongly correlates with the relative risk of stroke. Through the removal of atherosclerotic plaques, carotid endarterectomy (CEA) restores cerebral blood flow and reduces the risk of cerebral ischemia. While medical therapy clearly plays a role in the management of atherosclerosis in general and carotid artery disease in particular, the results from three major prospective contemporary studies provide compelling evidence for the benefit of CEA versus medical therapy alone. When performed by experienced surgeons, CEA, most prominently, improves the chance of stroke-free survival in high-risk symptomatic patients.
Asymptomatic carotid artery disease is highly prevalent in the general population, particularly the patient with evidence of other atherosclerotic disease and in the elderly. Compared with symptomatic stenosis, however, most available data suggest that asymptomatic carotid artery stenosis is associated with a relatively low risk of ipsilateral cerebral infarction.
In order to answer the question as to whether patients with symptomatic carotid stenosis were best treated medically or surgically, several clinical trials were conducted. All were criticized for design errors. Until the Asymptomatic Carotid Atherosclerosis Study (ACAS) was instituted, a truly prospective, randomized trial investigating the effect of surgical intervention on asymptomatic carotid lesions had not been adequately conducted. The ACAS was designed to evaluate the combined use of carotid endarterectomy and medical management (aspirin and risk factor modification) versus medical management alone for patients younger than 80 years with asymptomatic carotid artery stenosis of 60 percent or more.
Based on a five-year projection, the ACAS data show that carotid endarterectomy reduced the absolute risk of stroke by 5.9 percent and the relative risk of stroke and death by 53 percent. However, the surgical benefit incorporated a very low aggregate perioperative stroke and death rate of only 2.3 percent, including a permanent arteriographic complication rate of 1.2 percent. Essentially, the benefit of surgical intervention in this patient population is lost unless the operation is performed by an experienced surgeon with documented complication rate (combined arteriographic and surgical) of 3 percent or less. The results of ACAS have been criticized by several authorities based on the superior surgical success within the trial and a belief that such results cannot be duplicated in the surgical community as a whole. Therefore, because of the relatively low risk of stroke in asymptomatic patients, many authorities continue to recommend surgery in asymptomatic patients only when the degree of stenosis is more than 80 percent, as was demonstrated by ECST investigators.
Surgery for symptomatic carotid artery stenosis has the greatest impact with regard to stroke reduction. However, patients with high grade asymptomatic carotid occlusive disease (>80%) also enjoy a long-term reduction in stroke risk after CEA. The outcomes from surgical intervention have clearly been linked to the experience of the surgeon performing the procedure. All surgeons undertaking CEA should be able to honestly discuss their operative results with their patients to allow the patient to make an informed choice.
The traditional and time-tested, treatment for carotid occlusive disease is carotid endarterectomy (CEA). This procedure is done in the operating room under either general or regional anesthesia with the patient asleep. A 3 to 4 inch incision is made in the neck over the carotid artery and the branches are properly isolated. Once the blood flow is controlled a blood thinner is given and the surgeon opens the artery. He may choose to use a shunt to preserve the blood flow to the brain while the artery is opened. The plaque inside the artery is removed and the artery is closed back up either primarily or with a patch. A completion, intra-operative ultrasound is then performed to confirm that no technical defects remain. Local anesthetic is then injected in the wound so patients awaken nearly pain-free. The procedure lasts between 60 and 90 minutes. It requires an overnight stay in the ICU to monitor blood pressure and neurologic status. Patients usually are able to go home the next day. Post-operative activity restrictions are very few and most patients are back to full activity in one week.
As minimally invasive (angioplasty and stenting) techniques have advanced for the treatment of coronary and lower extremity arterial-occlusive disease, it became very appealing to consider such treatment for carotid occlusive disease. Thus, much attention has recently been given to percutaneous intervention for carotid stenosis - carotid angioplasty / stenting (CAS). The techniques for CAS require a high level of skill and are very specific for the treatment of this arterial bed. These procedures are performed in an angiogram suite. The femoral artery is accessed and catheters and a cerebral protection device are positioned in the area of blockage. The balloon is inflated, thus opening the artery, and a stent is placed simultaneously. Patients require overnight monitoring similar to CEA. Several trials have been completed comparing CAS with CEA. While CEA remains superior to CAS with regard to stroke and death, CAS has been shown to be beneficial in very high risk patients or those with inaccessible anatomic lesions.
The vascular surgeons at Sentara Martha Jefferson perform both procedures and has a very high success rate in doing so. In fact, in the combined > 30-year experience of the group not a single patient has sustained a stroke after a carotid intervention.