Comparing Carotid Stenting With Endarterectomy in Severe Asymptomatic Carotid Stenosis
Comparing Carotid Stenting With Endarterectomy in Severe Asymptomatic Carotid Stenosis
Purpose of this study:

 Primary:

 • Comparison of cardiovascular mortality and morbidity which includes cardiac and
 neurological morbidity (TIA and CVA) in the two invasive treatments of asymptomatic carotid
 artery stenosis

 Secondary:

 -  Comparison of non cardiovascular morbidity caused by the two invasive techniques

 1. morbidity at the site of incision (infection or local hematoma)

 2. damage to cranial nerves (hypoglossus, vagus)

 3. brain hyperperfusion which is defined as severe headache which is not responsive to
 analgesics with or without nausea and vomiting.

 4. events of bradycardia within the first 24 hours, clinically evident and/or silent

 -  microembolic brain events immediately after the procedure and their relationship with
 morbidity and/or mortality due to TIA's or CVA's

 -  the change in the stenotic carotid artery at the time of follow up with duplex of neck
 arteries

 -  the comparison of the affect of the two procedures on patient life style
Background: the surgical treatment of severe carotid artery stenosis (>70%) has been proven
 effective in prevention of cerebral vascular events in asymptomatic patients as compared with
 non invasive treatment (1, 5, 7). The currently accepted surgical treatment is called
 endarterectomy and includes surgery under regional and general anesthesia, in which the neck
 is opened, the common carotid artery, the bifurcation and the internal and external carotid
 artery are exposed, 5000 units of intravenous (IV) heparin is given and the arteries are
 occluded. The diseased artery is opened and the atherosclerotic plaque is excised, after the
 artery is cleaned the opening is sutured and the blood supply is reestablished. At the end of
 the procedure the incision is closed. The patient is transferred to recovery for four hours
 of surveillance, and 500 units/hour of heparin IV is started, which is continued for 12
 hours. After an additional day of surveillance in the department the patient is discharged
 home. Two weeks after the operation the patient is invited to the out patient clinic for
 wound surveillance and to take out the skin staples. After which the patient is under
 surveillance after 3 months, 6 months, and then yearly, which involves a physical examination
 by a physician and a duplex examination of carotid arteries. A regiment of 100mg of Aspirin
 per day is initiated at the time of diagnosis. Complications associated with this procedure:
 a 1-3% of patients develop a transient ischemic accident (TIA) or cerebrovascular accident
 (CVA), cardiac complications depending on individual risk factors (0.5%), bleeding and
 infection at incision site is at the rate of 5%, 2-8% of patients suffer from cranial nerve
 damage (including hypoglossus and vagus), 2-3% of patients suffer from brain hyperperfusion,
 finally, stenosis recurs in 10-15% of patients.

 Recently endovascular technique involving stent placement has been introduced to treat
 carotid artery stenosis. Early studies found this technique to be equal to traditional
 carotid endarterectomy in mortality and morbidity (8). Complications associated with
 endovascular stenting: 1-3% of patients develop a TIA or a CVA, bleeding at artery access
 site is at the rate of 1%, cardiac complications depending on individual risk factors (0.5%),
 1-4% of patients suffer from a periprocedural arterial thromboembolic events, finally, 1% of
 patients suffer from renal function deterioration. Invasive treatment of carotid artery
 stenosis, traditional or endovascular, may be accompanied by microembolic events, which, do
 not necessarily result in cerebral ischemia with evident neurological deficiency. These
 events, however, may be noted on brain CT and may result in cognitive decline (2-4%). The
 role of stent deposition in conjunction with a vascular protective device, in protecting from
 microembolic events is still unclear.

 In this study, price-rapid exchange® (Cordis, FL, USA) will be evaluated in the treatment of
 asymptomatic carotid artery stenosis. Traditional indications for stent placement will be
 used: stenosis of 70% or more demonstrated by carotid artery duplex, CTA or MRA. The stent is
 placed into the area of stenosed carotid artery using percutaneous approach in the operating
 room. The artery is visualized by injecting contrast material, a vascular protective device,
 angioguard® (Cordis, FL, USA), is placed downstream from carotid artery stenosis, the stent
 is inserted and expanded by a balloon, amiia® (Cordis, FL, USA). Furthermore, a completion
 angiography is preformed to visualize the final stent location and the protective vascular
 device is removed. A regiment of 100mg Aspirin, once daily, is initiated before endovascular
 treatment, and then continued as a part of a permanent treatment. Five thousand units of
 intravenous heparin are given at the beginning of the endovascular procedure. Heparin is than
 continued at 500 units per hour for the next 12 hours. The patient is discharged one day
 after the procedure.
Inclusion Criteria:

 -  Stenosis of 70% or more by carotid artery duplex, CTA or MRA.

 -  No evidence of TIA or CVA originating in area of the brain supplied by the carotid
 artery under study, in the four months preceding treatment.

 -  Eligibility for both treatment options:

 1. suited for operative treatment as assessed by an anesthesiologist

 2. suited for endovascular procedure by established radiological guidelines
 (including: access to the stenotic area via the vessels of the aortic arch, the
 absence of occlusion preventing this access, absence of significant
 atherosclerosis within the arch of aorta, absence of torturous anatomy of the
 common and internal carotid artery, and absence of thrombus in the area of
 stenosis)

 Exclusion Criteria:

 -