What is a Myocardial Infarction?
A myocardial infarction occurs when oxygenated blood is unable to reach heart muscle due to a block in blood supply. Myocardial infarction sounds foreign to most people. More commonly, myocardial infarctions are known as heart attacks. Heart attacks are among the leading killers of men and women in the United States.
What causes a heart attack?
Heart attacks are most commonly due to coronary artery disease (CAD), which is a build up of fatty plaque in arteries. What starts the cascade for the fat plaques? Endothelial damage, or more simply put, damage to the inner lining of the arteries. This leads to plaques that build up over the site of damage. Over time, the plaques harden and cause arterial narrowing. Eventually this may lead to a piece breaking off causing platelets (blood cell fragments) to stick to the injury site. When enough platelets stick together, they form a blood clot, which further narrows the already decreased diameter of the vessel. A muscle needs blood for oxygen in order to continue its function. This decreased diameter stops blood flow to heart muscle leading to tissue death.
Coronary artery disease has several risk factors. Major risk factors include: age, tobacco use, high blood pressure, high cholesterol, diabetes, family history, lack of physical activity, obesity and stress.
What can we do?
As much as most of us would love to be able to change our age and family history, those are factors we cannot control. However, the other factors are in our hands. Poor lifestyle habits can lead to obesity, high blood pressure, high cholesterol and diabetes. According to the American Heart Association (AHA), losing just 10% of your body weight can lower your risk of these cardiac risk factors. Decreasing body weight can be achieved through diet and exercise.
One study showed a vegan low-carbohydrate diet may reduce the risk of heart disease by 10% over 10 years. Important foods in this lifestyle include vegetables and fruit, specifically berries, as well as reducing salt intake to less than 2,300 mg of sodium per day. Vegetables and berries include nutrients that are all associated with a reduced risk for CAD such as fiber, folate, potassium, flavanoids and antioxidants. Research has revealed that the greater the intake of vegetables, the lower the risk of CAD. Those who ate at least 8 servings/day of fruits and vegetables had the lowest risk of CAD . Green leafy vegetables were shown to contribute the most to the protective effects for CAD.
Lack of physical activity is a major risk factor for heart disease. Exercise has been shown to lower blood pressure, which can decrease the overall risk of a heart attack. Women who performed moderate exercise reduced the risk of heart disease by 27%-41% . Exercise increases high-density lipoprotein (HDL), or good cholesterol, which actually protects against heart disease. Physical activity also decreases the bad cholesterol levels, low-density lipoprotein (LDL).
The American Heart Association recommends at least 30 minutes of moderate physical activity 5 or more days to reduce cholesterol levels, lower blood pressure and keep a healthy weight all of which contribute to reducing your heart attack risk. Moderate-level physical activities can be common household chores or sporting activities. Some examples of common chores as stated by the NIH include gardening for 30-45 minutes, stair walking for 15 minutes, pushing a stroller 1 ½ miles in 30 minutes or washing and waxing a car for 45-60 minutes. Some sporting activities that make the cut include walking 2 miles in 30 minutes, swimming laps for 20 minutes, running 1 ½ miles in 15 minutes, playing basketball for 15-20 minutes or playing volleyball for 45-60 minutes.
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5. Mayo Clinic. “Heart Attack.” Mayo Clinic, 20 May 2014.
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