context: It's easy to get them mixed up. Whether it's heart failure or a heart attack, your ticker isn't working the way it should. But there are big differences in what causes these conditions and how they make you feel. And which one you have will guide your doctor when he makes a treatment plan. A lot of things go on inside you that set up your troubles, but here's the big picture. When you have a heart attack, the flow of blood to your ticker is suddenly blocked. Heart failure, on the other hand, is a long-term problem. It happens when your heart doesn't pump enough blood through your body to meet its needs. A heart attack sometimes causes sudden and intense symptoms. More often, though, it starts with mild discomfort that gradually gets worse. You may get some of these: Chest discomfort. You may have a sense of squeezing, fullness, or pain in the center of your chest. It could last for more than a few minutes, or it might go away and come back. Pain in your upper body. You might hurt or feel uncomfortable in one or both arms or your back, neck, jaw, or stomach. Shortness of breath. This may happen to you with or without chest discomfort. You may also break out in a cold sweat, feel nauseous, or get light-headed. You can have it for years without any severe symptoms. When they do appear, they can include things like: Shortness of breath Persistent cough or wheeze Swelling in your feet, ankles, legs, or belly Weight gain Fatigue Lack of appetite or nausea Faster heart rate Any one of these on their own may not signal heart failure, but talk to your doctor if you have more than one symptom. Something called "coronary heart disease" sets you on the path to it. Over the course of your life, waxy plaque builds up on the insides of your blood vessels, which gradually narrows the passageway. You may hear your doctor call this process atherosclerosis. It speeds up if you're obese, you smoke, or have high cholesterol levels, high blood pressure, or diabetes. Sometimes plaque gathers in the coronary arteries -- the pipelines that carry oxygen-rich blood from your lungs to your heart. Sometimes all or part of the plaque breaks off the inside of your vessel wall, where it's been lodged, and causes a blood clot. If it gets big enough, it can completely cut off the blood flow through the artery. Since your blood no longer carries oxygen from the lungs to the heart, cells in the heart can die. If your heart muscle isn't getting enough oxygen or nutrients, it's called ischemia. When part of your heart muscle gets damaged as a result, it's called a heart attack. Less often, a heart attack is caused by a severe spasm in your coronary artery, without any signs of atherosclerosis. That happens most often in people who smoke or have high cholesterol or high blood pressure. When your heart is healthy, it works like a well-organized pump. It moves blood steadily through your lungs to pick up oxygen, then back out into the rest of your body. When everything goes smoothly, the right side of your heart pumps blood from the body and shuttles it over to the lungs. Meantime, the left side moves oxygen-rich blood back through the heart and out. When you've got heart failure, something goes wrong with the process. Your heart muscle may pump more weakly than usual and doesn't move as much blood. If the right side of the heart fails, your ticker can't pump enough blood to the lungs. If the left side has problems, your heart can't pump enough oxygen-rich blood out into your body. The two conditions can cause different symptoms, and in some people, both sides of the heart fail. Just like with a heart attack, the most common cause of heart failure is coronary artery disease. When the coronary artery narrows and cuts your blood flow, your heart can weaken. High blood pressure can also lead to heart failure since your ticker has to work harder than usual to move blood. Other things that play a role in heart failure are: Genetics Infections Alcohol or drug abuse Chemotherapy Long-term diseases like diabetes, HIV, hypertension, and hypothyroidism Abnormal heart rhythms All these can cause the heart to work in overdrive, weakening it over time. Whether you've had a heart attack or have heart failure, medicines and other options can help. Talk with your doctor and get a treatment plan in place.