Ways to prevent death due to sudden cardiac arrest (SCA) differ depending on whether:
                
You've already had SCA
                
You've never had SCA but are at high risk for the condition
                
You've never had SCA and have no known risk factors for the condition
                
For People Who Have Survived Sudden Cardiac Arrest
                
If you've already had SCA, you're at high risk of having it again. Research shows that an implantable cardioverter defibrillator (ICD) reduces the chances of dying from a second SCA.An ICD is surgically placed under the skin in your chest or abdomen. The device has wires with electrodes on the ends that connect to your heart's chambers. The ICD monitors your heartbeat.
                
If the ICD detects a dangerous heart rhythm, it gives an electric shock to restore the heart's normal rhythm. Your doctor may give you medicine to limit irregular heartbeats that can trigger the ICD.
                
Implantable Cardioverter Defibrillator
                

                
An ICD isn't the same as a pacemaker. The devices are similar, but they have some differences. Pacemakers give off low-energy electrical pulses. They're often used to treat less dangerous heart rhythms, such as those that occur in the upper chambers of the heart. Most new ICDs work as both pacemakers and ICDs.
                
For People at High Risk for a First Sudden Cardiac Arrest
                
If you have severe coronary heart disease (CHD), you're at increased risk for SCA. This is especially true if you've recently had a heart attack.
                
Your doctor may prescribe a type of medicine called a beta blocker to help lower your risk for SCA. Your doctor also may discuss beginning statin treatment if you have an elevated risk for developing heart disease or having a stroke. Doctors usually prescribe statins for people who have:
                
Diabetes
                
Heart disease or had a prior stroke
                
High LDL cholesterol levels
                
Your doctor also may prescribe other medications to:
                
Decrease your chance of having a heart attack or dying suddenly.
                
Lower blood pressure.
                
Prevent blood clots, which can lead to heart attack or stroke.
                
Prevent or delay the need for a procedure or surgery, such as angioplasty or coronary artery bypass grafting.
                
Reduce your hearts workload and relieve coronary heart disease symptoms.
                
Take all medicines regularly, as your doctor prescribes. Dont change the amount of your medicine or skip a dose unless your doctor tells you to. You should still follow a heart-healthy lifestyle, even if you take medicines to treat your coronary heart disease.
                
Other treatments for coronary heart diseasesuch as percutaneous coronary intervention, also known as coronary angioplasty, or coronary artery bypass graftingalso may lower your risk for SCA. Your doctor also may recommend an ICD if youre at high risk for SCA.
                
For People Who Have No Known Risk Factors for Sudden Cardiac Arrest
                
CHD seems to be the cause of most SCAs in adults. CHD also is a major risk factor for angina (chest pain or discomfort) and heart attack, and it contributes to other heart problems.
                
Following a healthy lifestyle can help you lower your risk for CHD, SCA, and other heart problems. A heart-healthy lifestyle includes:
                
Heart-healthy eating
                
Maintaining a healthy weight
                
Managing stress
                
Physical activity
                
Quitting smoking
                
Heart-Healthy Eating
                
Heart-healthy eating is an important part of a heart-healthy lifestyle. Your doctor may recommend heart-healthy eating, which should include:
                
Fat-free or low-fat dairy products, such as skim milk
                
Fish high in omega-3 fatty acids, such as salmon, tuna, and trout, about twice a week
                
Fruits, such as apples, bananas, oranges, pears, and prunes
                
Legumes, such as kidney beans, lentils, chickpeas, black-eyed peas, and lima beans
                
Vegetables, such as broccoli, cabbage, and carrots
                
Whole grains, such as oatmeal, brown rice, and corn tortillas
                
When following a heart-healthy diet, you should avoid eating:
                
A lot of red meat
                
Palm and coconut oils
                
Sugary foods and beverages
                
Two nutrients in your diet make blood cholesterol levels rise:
                
Saturated fatfound mostly in foods that come from animals
                
Trans fat (trans fatty acids)found in foods made with hydrogenated oils and fats, such as stick margarine; baked goods, such as cookies, cakes, and pies; crackers; frostings; and coffee creamers. Some trans fats also occur naturally in animal fats and meats.
                
Saturated fat raises your blood cholesterol more than anything else in your diet. When you follow a heart-healthy eating plan, only 5percent to 6percent of your daily calories should come from saturated fat. Food labels list the amounts of saturated fat. To help you stay on track, here are some examples:
                
If you eat:
                
Try to eat no more than:
                
1,200 calories a day              
                
8 grams of saturated fat a day    
                
1,500 calories a day           
                
10 grams of saturated fat a day
                
1,800 calories a day           
                
12 grams of saturated fat a day
                
2,000 calories a day           
                
13 grams of saturated fat a day
                
2,500 calories a day           
                
17 grams of saturated fat a day
                
Not all fats are bad. Monounsaturated and polyunsaturated fats actually help lower blood cholesterol levels. Some sources of monounsaturated and polyunsaturated fats are:
                
Avocados
                
Corn, sunflower, and soybean oils
                
Nuts and seeds, such as walnuts
                
Olive, canola, peanut, safflower, and sesame oils
                
Peanut butter
                
Salmon and trout
                
Tofu
                
Sodium
                
You should try to limit the amount of sodium that you eat. This means choosing and preparing foods that are lower in salt and sodium. Try to use low-sodium and no added salt foods and seasonings at the table or while cooking. Food labels tell you what you need to know about choosing foods that are lower in sodium. Try to eat no more than 2,300milligrams of sodium a day. If you have high blood pressure, you may need to restrict your sodium intake even more.
                
Dietary Approaches to Stop Hypertension
                
Your doctor may recommend the Dietary Approaches to Stop Hypertension (DASH) eating plan if you have high blood pressure. The DASH eating plan focuses on fruits, vegetables, whole grains, and other foods that are heart healthy and low in fat, cholesterol, and sodium and salt.
                
The DASH eating plan is a good heart-healthy eating plan, even for those who dont have high blood pressure. Read more about DASH.
                
Limiting Alcohol
                
Try to limit alcohol intake. Too much alcohol can raise your blood pressure and triglyceride levels, a type of fat found in the blood. Alcohol also adds extra calories, which may cause weight gain.
                
Men should have no more than two drinks containing alcohol a day. Women should have no more than one drink containing alcohol a day. One drink is:
                
12 ounces of beer
                
5 ounces of wine
                
1 ounces of liquor
                
Maintaining a Healthy Weight
                
Maintaining a healthy weight is important for overall health and can lower your risk for sudden cardiac arrest. Aim for a Healthy Weight by following a heart-healthy eating plan and keeping physically active.
                
Knowing your body mass index (BMI) helps you find out if youre a healthy weight in relation to your height and gives an estimate of your total body fat. To figure out your BMI, check out the National Heart, Lung, and Blood Institutes online BMI calculator or talk to your doctor. A BMI:
                
Below 18.5 is a sign that you are underweight.
                
Between 18.5 and 24.9 is in the normal range
                
Between 25.0 and 29.9 is considered overweight
                
Of 30.0 or higher is considered obese
                
A general goal to aim for is a BMI of less than 25. Your doctor or health care provider can help you set an appropriate BMI goal.
                
Measuring waist circumference helps screen for possible health risks. If most of your fat is around your waist rather than at your hips, youre at a higher risk for heart disease and type2 diabetes. This risk may be higher with a waist size that is greater than 35 inches for women or greater than 40 inches for men. To learn how to measure your waist, visit Assessing Your Weight and Health Risk.
                
If youre overweight or obese, try to lose weight. A loss of just 3percent to 5percent of your current weight can lower your triglycerides, blood glucose, and the risk of developing type2 diabetes. Greater amounts of weight loss can improve blood pressure readings, lower LDL cholesterol, and increase HDL cholesterol.
                
Managing Stress
                
Managing and coping with stress. Learning how to manage stress, relax, and cope with problems can improve your emotional and physical health. Consider healthy stress-reducing activities, such as:
                
A stress management program
                
Meditation
                
Physical activity
                
Relaxation therapy
                
Talking things out with friends or family
                
Physical Activity
                
Regular physical activity can lower your risk for coronary heart disease, sudden cardiac arrest, and other health problems. Everyone should try to participate in moderate-intensity aerobic exercise at least 2hours and 30minutes per week or vigorous aerobic exercise for 1hour and 15minutes per week. Aerobic exercise, such as brisk walking, is any exercise in which your heart beats faster and you use more oxygen than usual. The more active you are, the more you will benefit. Participate in aerobic exercise for at least 10minutes at a time spread throughout the week.
                
Talk with your doctor before you start a new exercise plan. Ask your doctor how much and what kinds of physical activity are safe for you.
                
Read more about physical activity at:
                
Physical Activity and Your Heart
                
U.S. Department of Health and Human Services, 2008 Physical Activity Guidelines for Americans
                
Quitting Smoking
                
People who smoke are more likely to have a heart attack than are people who dont smoke. The risk of having a heart attack increases with the number of cigarettes smoked each day. Smoking also raises your risk for stroke and lung diseases, such as chronic obstructive pulmonary disease (COPD) and lung cancer.
                
Quitting smoking can greatly reduce your risk for heart and lung diseases. Ask your doctor about programs and products that can help you quit. Also, try to avoid secondhand smoke. If you have trouble quitting smoking on your own, consider joining a support group. Many hospitals, workplaces, and community groups offer classes to help people quit smoking. Read more about how to quit smoking.