An abnormally low heart ejection fraction is 40 percent or below, a measurement that may indicate cardiomyopathy or heart failure, according to the American Heart Association. An abnormally high heart ejection fraction is 75 percent or greater, which may indicate hypertrophic cardiomyopathy or other heart conditions.
The normal heart ejection fraction rate is between 55 and 70 percent, notes the American Heart Association. Readings that fall in this range indicate that the heart pumps 55 to 70 percent of the total amount of blood in its left ventricle with every beat. A measurement of 40 to 55 may indicate previous damage, possibly from earlier heart attacks.