With heart failure, either the heart can't fill with enough blood or it doesn't pump with enough force. If you have heart failure, it does not mean that your heart has stopped or is about to stop working. It means that your heart is not able to pump blood the way it should. This condition is called "congestive" heart failure when this inability leads to heart failure symptoms, such as tiredness and shortness of breath; blood and fluid backing up into the lungs; and fluid building up in the feet, ankles, and legs. As congestive heart failure progresses, symptoms tend to worsen. Some other names for heart failure besides congestive heart failure include left-sided heart failure, right-sided heart failure, systolic heart failure, and diastolic heart failure.