Treatments for CAD vary according to the severity of the disease, the location of any blockages in the blood vessels, the presence of any risk factors (e.g., abnormal cholesterol profile or high blood pressure) and the overall health of the patient. Options include lifestyle changes, medication, and interventional and surgical techniques.
Medications used to treat CAD fall into the following categories:
* Beta blockers. Medications that reduce the workload of the heart by blocking certain chemicals from binding to beta receptors in the heart.
* Nitrates. Medications that cause blood vessels to relax and dilate, allowing more oxygen-rich blood to reach the heart.
* Calcium channel blockers (calcium antagonists). Medications that increase blood flow through the heart and may reduce the workload of the heart by blocking calcium ions from signaling the blood vessels to constrict or tighten.
* Antiplatelets (e.g., aspirin, clopidogrel). Medications that inhibit the formation of blood clots by decreasing the ability of platelets (a clotting component of the blood) to bind together and form a blood clot.
* Statins. A type of cholesterol-reducing drug that lowers the levels of fats (lipids) in the blood, including cholesterol and triglycerides. Statins work by blocking the production of specific enzymes used by the body to make cholesterol. They are effective in lowering blood fat levels in patients with high cholesterol (hypercholesterolemia) and are therefore helpful in the prevention of coronary, cerebrovascular and peripheral vascular disease.
* Other drugs that interfere with the absorption of cholesterol from the intestinal tract (e.g., ezetimibe, fibrates, bile acid resins).
There are several main procedures used in the treatment of CAD:
* Balloon angioplasty. A procedure in which the physician guides a balloon-tipped catheter into the blocked coronary artery, then rapidly inflates the balloon. This crushes the plaque against the artery wall, thus allowing more blood to flow through the widened vessel. A major problem with this approach is the gradual reclosure of the vessel (restenosis). The recent introduction of stents has somewhat helped this problem. These tiny wire mesh tubes are implanted in the artery after angioplasty. They hold the plaque against the wall and help prevent the vessel from closing again. Newer stents, known as drug-eluting stents, are available. These drug-eluting stents have been coated with special drugs that further help reduce restenosis. Drug-eluting stents were initially rapidly accepted by physicians and used in the majority of situations. However, new research has revealed that drug-eluting stents may increase the risk of blood clots in certain situations and physicians are currently studying the best applications for both drug-eluting stents and the older bare-metal stents.
Balloon angioplasty and stenting are procedures to increase blood flow through a narrowed artery. Atherectomy involves using a bladed device to cut or grind away hardened plaque in arteries.
* Atherectomy. Another catheter-based procedure in which the physician guides a special catheter into the blocked coronary artery. This catheter is equipped with a blade that cuts away the soft plaque deposits, or a grinding burr that pulverizes harder, calcified plaque
* Coronary artery bypass graft (CABG). A surgery that increases blood flow to the heart by creating a detour and re-routing the blood flow around the blocked portion of the artery. A section of a blood vessel from another part of the body (e.g., the leg or chest) is relocated and grafted above and below the damaged portion of the coronary artery to form an open channel around the blockage. Traditionally, this surgery is performed with use of the heart-lung machine, which supports the patient’s circulation while the surgeon operates on the heart. Today, however, about 25 percent of CABG surgeries are performedBypass surgery creates a detour around a blocked artery using a blood vessel from another body area. as off-pump bypass procedures. In this case, portions of the beating heart are held still with special stabilizers while the surgeon performs the operation through a traditional incision. This reduces side effects associated with the use of the heart-lung machine.
* MIDCAB (minimally invasive bypass surgery). This is a less traumatic form of the traditional bypass graft surgery that relies on smaller incisions to gain access to the chest cavity. While MIDCAB is effective in some situations, such as patients who have limited disease in one or two main coronary arteries, the procedure is not commonly used. MIDCAB is sometimes used in conjunction with coronary angioplasty to treat multi-vessel disease.
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