SN instructed patient that heart failure, also called Congestive Heart Failure (CHF), means your heart does not pump blood as well as it should. This does not mean your heart has stopped working, but that it is not as strong as it used to be and fluid builds up in the lungs and other parts of your body. This can cause shortness of breath, swelling in the legs, feet, and stomach. Heart failure starts slowly and can get worse over time.