You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
What is What is the normal left ventricular ejection fraction? and explain in detail?
Normal left ventricular ejection fraction ranges from 55% to 70%. It is the measurement of how much blood is pumped out of the left ventricle of the hea in each contraction . It is expressed in percentage. If the EF is below normal value, it can be a sign of hea failure