Blockages of the carotid artery are a leading cause of stroke. Lifestyle changes and medications can prevent and treat blockages of the two largest blood vessels that supply oxygen-rich blood to the brain. When blockages become large, patients require one of two surgeries to clear the material that is impeding blood flow from the heart and lungs to the brain.
Types of Blockages
The carotid arteries, which run up both sides of the neck, can become blocked by the build-up of cholesterol and other fatty substances, or plaques, along the wall of the arteries. The arteries can also get blocked by blood clots that form in the carotid arteries or by blood clots that travel from other places in the body. The type of treatment used when a carotid blockage is detected during physical testing or after a stroke depends on the degree of arterial occlusion and the nature of the material causing the blockage.
Patients with any type of carotid artery blockage should take steps to address the condition. The first step is to change behaviours that led to the formation of the blockage. Following a healthy diet low in fats and salt, quitting smoking, reducing or eliminating daily alcohol consumption and exercising more will slow the deposition of cholesterol in blood vessels. Getting more exercise can also help prevent blood clots, because clots are more likely to form during periods of prolonged inactivity.
Carotid artery blockages of less than 50 per cent can usually be managed and reduced with a combination of lifestyle changes and medication. Physicians prescribe anticoagulants such as aspirin and warfarin to slow the growth of blood clots and may use a clot-busting, or thrombolytic, drug such as retaplase (Retevase from Centocor) to dissolve a large clot. Similarly, medications such as dofetilide (Tikosyn from Pfizer), which controls irregular heartbeat, and fondaparinux (Arixtra from GlaxoSmithKline), which treats deep vein thrombosis, can play roles in controlling carotid artery blockages by preventing the formation and travelling of clots through the body. Options for lowering cholesterol and other substances that can stick to artery walls include atorvastatin (Lipitor from Pfizer), colesevelam (Welchol from Daiichi Sankyo), fenofibrate (e.g., Antara from Oscient), gemfibrozil (e.g., Lopid from Pfizer), lovastatin (e.g., Mevacor from Merck), niacin (e.g., Niaspan from Abbott), and simavastatin (e.g., Zocor from Merck).
A surgery called an endarterectomy removes large plaques from the carotid artery. During the procedure, a surgeon slices open the blocked blood vessel and physically scrapes out the cholesterol and other material that should not be in the carotid artery. Endarterectomies have a high success rate in terms of reopening arteries but require full anaesthesia and hospital stays of one or two days. Full recovery from a carotid endarterectomy can take a month, and the procedure carries small risks of bleeding in the brain, brain damage, seizure, stroke and swelling around the airway (pharynx and larynx).
Angioplasty and Stenting
Carotid angioplasty and stenting is an alternative for patients whose current health, previous surgeries or blockage location make them poor candidates for an endarterectomy. Patients remain awake during this alternative procedure, in which a surgeon inserts a catheter in the blocked artery, inflates a balloon on the end of the catheter to flatten out the plaque, and leaves behind a stent when withdrawing the catheter. The stent is a small mesh cylinder that holds the artery open. Patients generally require only one night's stay in the hospital following a carotid angioplasty and stenting and can resume their normal activities almost immediately. Like a endarterectomy, a carotid angioplasty and stenting carries a small risk of brain injury.