context: " Heart failure" sounds like your heart has completely stopped working -- but it hasn't. What it really means is that your heart can no longer pump enough blood to give your body the oxygen it needs. When you have advanced heart failure, you may need an artificial pump put into your chest or even a heart transplant. But in the meantime, your body has to adapt to keep working with less oxygen. Your doctor may describe your heart failure based on the strength of your heart and how your body is responding. Compensated heart failure means your heart works well enough that you either don't notice any problems or the symptoms are easy to manage. You don't have fluid buildup in your legs and feet, and you can breathe without trouble. Your body still seems to be doing OK, even with the change in your heart's pumping ability. Decompensated heart failure describes obvious symptoms that affect your overall health and quality of life; for example, congestion in your lungs that makes it harder to breathe, so you wheeze or cough. Decompensated heart failure can also make you feel tired and could make it harder to exercise or even do simple things like folding laundry. You may have abnormal heart rhythms (arrhythmias). At first, the heart will try to make up for underperforming: The chambers expand to allow more blood to move with each heartbeat. It contracts, or squeezes, more strongly. The muscle thickens so it can pump with more force. It beats faster. One problem with this is that, over time, an enlarged heart leads to fluid building up in your body, including the lungs. Because blood isn't moving well out of the heart, it backs up coming in. Veins swell, and tissues can't send back the blood without oxygen. When your heart beats much faster than its normal rate, it's called tachycardia. This tends to happen in decompensated heart failure. Tachycardia can lead to several complications, including blood clots in the heart and fainting. The extra heartbeats can also weaken the heart muscle further. The downside of all this is that your heart can't keep it up, so after a while, it just won't be able to pump blood throughout your body anymore. Early on, your blood vessels get narrower, which raises your blood pressure to make up for the loss of power. But narrowed blood vessels are less elastic. This makes it harder for blood to move through them. Your heart has to work harder, and heart failure gets worse. Your body also prioritizes where the oxygen should go. It will send more blood to important organs, such as your brain and heart, and divert blood away from other organs, muscles, and tissue. As a result, poor circulation in your arms and legs may lead to problems with everyday tasks, such as walking. Because your body can make up for the early stages of heart failure, you may not know you have a problem that needs attention. Regular physicals and doctor checkups can help you catch heart failure as it's developing, so you and your doctor can work together to try to prevent or hold off some of the problems it can cause. Heart failure is a chronic disease, meaning it's a long-term health challenge. It's not something that can be cured. Medications and devices such as artificial pumps can help you manage symptoms and keep up your quality of life. You'll also need to follow your doctor's advice about treatment and healthy lifestyle habits.