The ejection fraction, or EF, refers to the amount of blood pumped out of the heart with each beat. Ejection fraction is an important measure of how well your heart muscle is functioning. Normal EF is greater than 55%. People with a decreased EF, called cardiomyopathy is frequently caused from coronary disease. This causes heart failure or CHF, and puts people at risk for sudden death. You may need an ICD-defibrillator if you are at risk for sudden cardiac death.