Angioplasty and stenting for the treatment of cerebrovascular disease has grown in recent years. It is known that patients with symptomatic carotid stenosis of more than 70% benefit from intervention. Carotid endarterectomy (CEA) has been the gold standard for treatment with a 9% stroke rate compared to 26% with medical treatment over 2 years and a 3.3 % risk of cerebrovascular event according to the North American Symptomatic Carotid Endarterectomy Trial (NASCET). The Carotid Revascularization: Endarterectomy versus Stent Trial (CREST) is currently under way to compare CEA to stent placement in a standard population. In high risk patients, the Stenting and Angioplasty in Patients with Protection in Patients at High Risk for Endarterectomy (SAPPHIRE) Trial has shown that carotid stenting with a distal protection device is safer than CEA with a Major Adverse Event rate of 11.9% vs. 19.9% at one year. Patients in this group include those with previous neck surgery, radiation treatment, high carotid artery bifurcation, cardiac or pulmonary disease and poor general anesthesia risk. There are no trials for the treatment of disease of the carotid artery origins, vertebral arteries or intracranial stenoses, but these areas are accessible to Neurointerventionalists.
Patients are screened for this procedure by a team of physicians including Interventional Neuroradiology, Neurosurgery and Neurology. This insures a patient is selected by proper criteria and receives long-term follow up. Typically, a patient should be symptomatic and have at least 70% stenosis of the affected carotid artery. Patients may have had previous stroke or TIA’s. Most will have undergone MRI/MRA or CTA and carotid/Transcranial Doppler Ultrasound to determine if an artery is narrow. If a patient has had a stroke, the procedure may be done several weeks afterward to limit the chances of bleeding from the anticoagulation regimen used in stenting. Medication instituted prior to the procedure includes aspirin and plavix with heparin used during the procedure itself. This prevents clot from developing on the catheters or stent and causing a stroke.
The procedure is done under monitored anesthesia care with the patient sedated but awake or with general anesthesia depending on medical condition. Under sterile conditions the femoral artery is accessed in the right or left groin area. A sheath is placed through which a catheter is placed for diagnostic angiography. This shows the Neurointerventionalist the precise location and degree of narrowing in the artery and the collateral circulation around the brain. Under direct fluoroscopic visualization, a guide catheter is placed in the affected artery, and a small guide wire is passed beyond the stenosis. This wire may have a built in protection device to collect any debris from the angioplasty, which follows. The next step is placement of the stent over this guidewire and possibly a second angioplasty to secure the stent in place. Any debris collected by the protection device is retrieved, and the catheters are removed. Patients are continued on aspirin and plavix and followed by our staff and Neurology following discharge from the hospital
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