General Description
Cardiovascular diseases are the leading causes of death in the United
States, claiming more than one million lives per year. While most
cardiovascular deaths result from myocardial infarction
(heart attack) or stroke, there are several conditions that fall
under the category of cardiovascular disease, including cardiomegaly,
cardiomyopathy, carditis, endocarditis,
hypertension, coronary heart disease, congestive heart
failure, and atherosclerosis. Many of these conditions are interrelated
and contribute to each other's progression.
Coronary heart disease
Coronary heart disease (CHD), the most common form of heart disease,
is the number-one killer of men and women in the U.S. Each year
over 500,000 Americans die of heart attacks caused by CHD. CHD
is a condition in which the arteries that carry blood to the heart
become narrowed or clogged and cannot deliver enough blood. Insufficient
blood supply to the heart may cause pain (angina), which is usually
felt in the chest, or sometimes in the left arm and shoulder.
When the blood supply is cut off completely, myocardial infarction
(heart attack) results. Parts of the heart not receiving oxygen
begin to die, and the heart muscle may be permanently damaged.
Contributing factors for CHD
CHD results from narrowing or blockage of coronary arteries due
to atherosclerosis. Atherosclerosis is a form of arteriosclerosis
(hardening of the arteries) caused by the buildup of fatty deposits
(plaque) on artery walls. This most often occurs in people with
high levels of cholesterol and triglycerides in their blood. In
addition to high blood cholesterol, influences such as smoking,
high blood pressure, high homocysteine levels,
age, and hereditary predisposition can contribute to atherosclerosis
and CHD. Obesity and physical inactivity are other factors that
can lead to CHD. Overweight people are more likely to have high
blood pressure and high blood cholesterol, and inactivity increases
the risk of heart attack. Regular exercise, smoking cessation,
and good nutrition are important for controlling the risk factors
for CHD.
Conventional treatments
CHD is treated in various ways, depending on the seriousness of
the disease. While severe cases may require surgery, for many,
CHD can be managed with medication and lifestyle changes. Medications
are prescribed according to the patients symptoms and risk factors.
Angina is often treated with "beta blockers" that decrease the
workload of the heart, nitroglycerin and other nitrates, and "calcium
channel blockers" that relax the arteries. Aspirin, warfarin,
and other anticoagulant drugs help reduce blood clotting. Cholesterol-lowering
drugs may be prescribed for those with elevated cholesterol levels
that don't respond to dietary measures. Impaired heart pumping
capacity is treated with digitalis or with ACE inhibitor drugs.
Nutritional considerations
Nutritional considerations for CHD should focus on maintaining
healthy blood pressure, cholesterol, and homocysteine levels.
High sodium intake has been linked to hypertension, and limiting
salt and other sources of sodium in the diet improves this condition
in some people.1-3 Some studies suggest that including
adequate potassium, calcium, and magnesium in the diet may be
as important as limiting sodium intake for controlling hypertension.4,5
A high-fiber, low-fat diet is recommended to help keep cholesterol
levels under control. Omega-3 fatty acids, such as those found
in fish oil, are beneficial because they help reduce cholesterol
and triglyceride levels while promoting a healthy ratio of "good"
(HDL) and "bad" (LDL) cholesterol.6-8 The B-complex
vitamin niacin also aids in lowering cholesterol levels.9,10
Dietary antioxidants may be helpful because they protect LDL from
oxidation (oxidized LDL is believed to be a major contributor
to atherosclerosis), and they protect blood vessel walls from
oxidative damage. Folic acid, vitamin B-12, and vitamin B-6 play
important roles in controlling homocysteine levels.11-12
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