The term congestive heart failure is often used to describe all patients with heart failure. Congestion refers to the buildup of fluid. This is just one feature of the condition and it does not occur in all patients. This occurs when the heart's ability to contract decreases. The heart cannot pump with enough force to push a sufficient amount of blood into the circulation.
Ejection fraction is the percent of the blood pumped out every time the heart beats.
Blood coming into the heart from the lungs may back up and cause fluid to leak into the lungs. This is called pulmonary congestion. Systolic heart failure is the most common type. This occurs when the heart has a problem relaxing. The heart cannot properly fill with blood because the muscle has become stiff, losing its ability to relax.