We all owe our lives to the arteries that carry oxygen-rich blood from our lungs to our heart. If one of those arteries becomes blocked, part of the heart will begin to die. Doctors call this sudden blockage an "acute myocardial infarction," but it's also known as a heart attack.
The pain of the attack itself may last for minutes or hours, but the roots of the problem often stretch back several decades. Many people start to develop small streaks of cholesterol and other fats in their arteries before they turn 10 years old. If the fats continue to build up over the years, the streaks turn to fatty clumps or "plaque," the hallmark of atherosclerosis. If the arteries that feed the heart become narrowed by these plaques, a condition called coronary heart disease, a heart attack may be just around the corner.
Here's a typical heart attack in action: With little or no warning, a chunk of plaque begins to break. As the fat and contents of the plaque mix with blood, the blood forms a large clot. The clot then blocks the artery, cutting off all the blood flow to that part of the heart. Within 20 minutes, parts of the heart muscle begin to die.
Heart attacks damage the heart muscle, often with deadly results. Of the 1.1 million people in the U.S. who have heart attacks in any given year, close to half of them die. In up to 50 percent of people who have heart attacks, the attack is the first sign that they have coronary heart disease. You can improve your chances of surviving a heart attack by understanding and reducing your risk for an attack, recognizing the symptoms, and knowing when to get help.
Who is at risk for a heart attack?
Anyone who has already had a heart attack is a prime target for another one. Furthermore, anything that encourages coronary heart disease can put you at risk, including the following:
Reversible risk factors
High blood pressure
Current smoking (within the last six months)
Lack of exercise
Irreversible risk factors
Age (over 45 for men or over 55 for women)
Family history of premature heart disease (your father or first-order male relative had a heart attack under 45 years of age, or your mother or first-order female relative had a heart attack under age 55)
Prior heart attack (myocardial infarction)
When do heart attacks most often occur?
Heart attacks can strike at any time of day, during any type of activity. However, they often follow a pattern. Due to the daily ebb and flow of hormones that affect the arteries and the state of the heart, heart attacks are most common in the morning. Furthermore, about half of all victims can point to a "trigger," a specific event that seemed to set the attack in motion. Possible triggers include heavy exertion, sex (in very rare cases), anger, cold or hot weather, fear, grief, smoking, heavy drinking, and even large meals.
What are the symptoms of a heart attack?
Some heart attacks follow the classic Hollywood script: The victim suddenly experiences an intense, crushing pain right beneath the breastbone that leaves victims clutching their chest. Many people feel extreme pressure, as if someone piled a load of bricks on their midsection. Others describe the pain as burning or knife-like. The pain often spreads down the arms (especially the left arm) and to the shoulders, neck, and jaw. Unlike angina pectoris -- chest pain caused by decreased blood flow to the heart and often relieved by nitroglycerin -- the pain of a heart attack will probably last at least 30 minutes and won't get better if you rest.
Pain isn't the only symptom of a heart attack. Many people also experience shortness of breath, weakness, nausea, dizziness, fainting, or heavy sweating; women, in particular, are likely to feel indigestion and nausea rather than crushing chest pain. In fact, some people don't feel any chest pain at all. So-called "silent" heart attacks are especially common in people over 75, and in people with diabetes.
What should I do if I think I'm having a heart attack?
If you think you might be having a heart attack, call 911 RIGHT AWAY. There's no time to waste -- prompt medical treatment can protect your heart from damage and may even save your life. This may seem like obvious advice, but many heart attack victims hesitate to pick up the phone because they don't recognize the symptoms. For instance, many people who have diabetes or are over 75 don't realize nausea and shortness of breath could be the only sign of an attack.
After making the call, you should take one aspirin tablet (some suggest chewing it). Aspirin can help increase your chances for survival.
How are heart attacks treated?
Once you're in the hospital, a doctor will review your history and examine you. He or she will perform an electrocardiogram (EKG) and run blood tests to diagnose the cause of your pain. If you are having an attack, the doctor and the hospital will set into motion a team to try to open the artery that is responsible for the attack. In hospitals where a catheterization laboratory is not available, the doctor can prescribe medications to break up the blood clot, boost the heart's pumping power, and reduce the work of the heart.
After the episode is over, you may need angioplasty, bypass surgery, or other treatments to improve blood flow to your heart and prevent future attacks. You will definitely need further evaluation to determine your risk, and will likely be placed on medication to prevent future events.
How can I avoid a heart attack?
First of all, see your doctor for a checkup and an evaluation of your risk factors. Starting at age 20, the American Heart Association recommends that everyone be evaluated by a doctor for risk factors. Your doctor should check your blood pressure, body mass index, waist measurement, and pulse at least every two years, and monitor your cholesterol and glucose levels at least every five years. If you're 40 or over or have multiple risk factors, the AHA recommends that your doctor calculate your 10-year risk of developing cardiovascular disease every five years (more often if risk factors change). You can also calculate your own risk online by using the AHA's risk assessment tool.
With your doctor's help, control or eliminate as many risk factors as you can. If you smoke, stop. Exercise regularly and eat a healthy diet low in saturated fats (animal fats like butter and cream) and trans fats (found in french fries and many processed foods). Keep your weight at a desirable level, and if you have diabetes work to keep your blood glucose near normal levels.
If your blood pressure or cholesterol levels are still too high despite your healthy lifestyle, you may need prescription medications to bring them under control. The National Cholesterol Education Program recommends that patients at very high risk for heart attacks try to reduce their LDL (bad) cholesterol levels below 70 mg, which for most people will require taking cholesterol-lowering drugs. The AHA recommends that people at higher risk of coronary heart disease take a low dose of aspirin (75-160 mg per day) as long as they don't have aspirin intolerance or a risk of bleeding.
If you or anyone you know is at risk of a heart attack, you may want to encourage your workplace to purchase and implement an automatic external defibrillator (AED) program on site. Although this equipment used to be operated only by appropriately trained and certified personnel, it is increasingly common for airlines, casinos, and other workplaces that deal with the public to be equipped with an AED and have employees trained to use it.
Above all, be prepared. The healthiest lifestyle in the world won't make you immune to heart attacks. But if you know how to respond, the number-one killer in the United States will be much less dangerous.
Heart Information Network. Center for Cardiovascular Education. Heart attack guide: Part one -- heart function, symptoms of a heart attack, emergency care, tests, treatments.
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National Heart, Lung, and Blood Institute. What Is A Heart Attack? http://nihseniorhealth.gov/heartattack/whatisaheartattack/03.html
American Heart Association. Updated guidelines advise focusing on women's lifetime heart risk. Journal Report. http://www.americanheart.org/presenter.jhtml?identifier=3045524.
American Heart Association. Primary Prevention in the Adult. http://www.americanheart.org/presenter.jhtml?identifier=4704.
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