A normal ejection fraction is __________% or greater.

The ejection fraction (EF) is a key measurement used to assess the heart's efficiency in pumping blood. It is defined as the percentage of blood that is ejected from the ventricles with each heartbeat relative to the total amount of blood in the ventricles. A normal ejection fraction indicates that the heart is functioning well and can pump sufficient blood to meet the body's needs.

A normal ejection fraction is typically considered to be 55% or greater, with many clinical guidelines generally using a cutoff of around 60% to indicate good ventricular function. This percentage signifies that the heart is effectively ejecting a significant portion of the blood it contains, ensuring adequate circulation.

In contrast to other options, which indicate lower percentages that fall into the range of heart dysfunction or heart failure evaluations, the range of 50% or greater is recognized in many scenarios as the threshold for identifying normal versus reduced cardiac function. While 60% is often cited as an ideal target, the accepted range for normal ejection fraction spans from 55% and higher. Hence, 50% has been established as a minimum for normal function in some contexts, particularly in certain patient populations or under specific clinical evaluations. This makes the response acceptable within varying definitions surrounding cardiac health.