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Coronary Artery Disease and Peripheral Vascular Disease
Coronary Artery Disease (CAD) is also called ischemic heart disease and is
the leading cause of death in the United States. Ischemia occurs when
there is a loss of blood flow through the coronary arteries to the
myocardium. If left untreated this situation leads of myocardial
infarction. The loss of blood flow occurs when an artherosclerotic plaque
occludes one or more coronary arteries. Artherosclerotic plaques consist of
many substances including fibrin, cholesterol, and calcium.
Artherosclerosis is not limited to coronary arteries. When plaques form
in the carotid arteries of the neck TIAs and strokes may occur. If plaques
form in the abdominal aorta an aneurysm (abnormal dilation) may
form and eventually rupture. Plaques in the iliac or femoral arteries cause ischemia to the lower
extremities causing claudication, the primary symptom of peripheral vascular disease.
Currently, coronary artery disease is treated using three methods.
Pharmacologic therapy, which includes the use of drugs such as beta
blockers, calcium channel blockers and nitroglycerine to dilate the coronary
arteries, improve blood flow to cardiac muscle and decrease work of the heart
(which consequentially decreases the demand of cardiac muscle for blood). Sometimes drugs to lower a persons' LDL
and triglycerides may be prescribed to reduce risk factors. Angioplasty
involves passing a catheter through the arterial circulation to the coronary
arteries and using a balloon to dilate the arteries. Following the
dilation of the artery a stent may be place to inhibit reocclusion. Finally,
there is coronary artery bypass graft (CABG) surgery where a venous graft from
the leg or arm of the patient is used to bypass the arterial
occlusion. Surgery is usually the treatment of choice for carotid artery stenosis,
aortic aneurysms, and claudication. Lifestyle modification can be an
important adjunct to medical management of CAD.
Peripheral vascular disease can also be treated in several
different ways depending on the severity, acuity and etiology of the disease.
Lifestyle changes including smoking cessation, regular exercise and diet
modification are first line therapy for peripheral vascular disease.
Pharmacologic treatment uses medications designed to inhibit clot formation
(aspirin and clopidogrel) and lower cholesterol levels (statins).
Angioplasty, thrombolysis/thrombectomy and bypass grafting can be used to
recannalize or bypass occluded arteries.
Proponents propose that chelation therapy is another viable form of therapy used to
treat these diseases. The physiologic mechanism of chelation therapy
varies depending on which of its proponents you ask. The more common
explanations are that chelation therapy scavenges metal ions and decreases the
number of free radicals or that calcium, and not cholesterol, is most important
constituent of atherosclerotic plaques and arterial hardening and by removing
calcium from the body this process can be reversed. More information about potential mechanisms of action
can be found on the chelating
agents page. |
