Cardioprotection

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Cardioprotection

As the phrase suggests, cardioprotection is any physical or nutritional measure that guards against injury or harm to the heart and its function, with respect to any of the bodily systems in which it is a component, including the cardiovascular, cardiopulmonary, and cardiorespiratory systems.

There are various ways to help protect the heart. Regular physical exercise is important as there exists overwhelming scientific evidence that physically active people have both a lower incidence of coronary disease generally, as well less likelihood of sustaining a ischemia-reperfusion injury, commonly known as heart attack. Physically active persons also tend to survive the cellular damage caused to heart muscle by a heart attack better than physically inactive persons. Another good routine is taking nutritional antioxidants, including vitamins C and E.

The principles of cardioprotection are best understood in the context of what happens to the heart muscles and arteries during an attack. The coronary arteries (those that flow directly into the heart muscle) can become clogged with a plaque substance that is a buildup within the walls of the artery. The plaque is composed of cholesterol, a soft, fat-like, waxy substance that adheres to the artery wall, causing the artery to narrow—a condition known as arteriosclerosis. The clogged artery does not permit optimum blood flow, and there is a corresponding reduction in the ability of the body to deliver oxygen to the heart muscle.

A heart attack will occur where there is an arterial blood clot that causes a reduction of blood to the heart. The period between the reduction in blood flow and the resumption of a regular flow is the measure of the severity of the heart attack. When the blood flow to the heart is interrupted for less than five minutes, the heart will typically recover normal function, with minimal damage. However, when the blood flow to the heart is interrupted for a period in excess of 20 minutes, the cells of the heart muscle sustain permanent, irreversible damage, as cardiac cell muscles do not regenerate. This cell damage results in a permanent loss of heart function and capacity to pump blood.

Heart disease can be accelerated through a number of factors, such as cigarette smoking, the use of narcotics, or diet. Such factors aside, there is a clear correlation between the amount of exercise performed by an individual and the risk of coronary disease. While physical exercise is a certain cardio-protector, the quantity and the intensity of the exercise are factors that will determine the extent of the protection. Generally, the greater the intensity level of the regular exercise activity, the less risk of a heart-related illness.

Regular physical exercise, defined as a minimum of four sessions of 30 minutes duration per week, where the energy demands are a minimum of 250 calories per session, tends to reduce the risk of other related heart conditions, chiefly hypertension (high blood pressure), high cholesterol, and diabetes.

The same minimum level of physical exercise will protect the heart against the damage caused in attacks that threaten permanent cardiac injury due to heart cell death. Exercise promotes better collateral circulation in the body, providing the blood with a number of alternate avenues for circulation. Exercise is also believed to facilitate the production in the heart muscle of certain proteins, referred to as heat shock proteins, that strengthen these muscles when exposed to the stress of a heart attack.

Antioxidants are those compounds that operate within the body to slow the destruction of cells. An antioxidant will tend to seek out and neutralize molecules known as radicals, which are a byproduct of chemical processes within the body and which, if left to operate within the bloodstream, tend to speed the destruction of cells. It is known that when vitamin C, vitamin E, and alpha lipoic acid are all present in the cells of the heart muscle, there is protection afforded against the cellular injury of prolonged heart attack. Vitamin E is a fat-soluble compound that is the most commonly found antioxidant in nature. Vitamin C is a natural, water-soluble substance that works in partnership with vitamin E. Alpha lipoic acid is a water-soluble acid that works with vitamin C.

While all of the antioxidants identified as cardio-protectors occur naturally in foods, nutritional supplements are a further means to ingest these compounds. Multivitamins are a common source of these cardioprotectors. As with any supplement, the regular consumption of any supplement that is in excess of the daily requirements of the body creates another set of health risks. Each of these antioxidant compounds is toxic if consumed in excessive amounts.

see also Cardiovascular system; Dietary supplements; Genetics; Vitamin E.