Ejection fraction is an important indicator in echocardiography because it will help doctors identify systolic dysfunction or evaluate the degree of left ventricular function decline, and is meaningful in evaluating the effectiveness of the treatment in patients with heart failure.

Heart failure is the ultimate common pathway of cardiovascular diseases. Heart failure is divided into two types, acute heart failure and chronic heart failure. Acute heart failure can be a new-onset heart failure, but it can also be an aggravation of chronic heart failure.

Besides clinical symptoms, medical history, blood tests... ejection fraction (EF) is an important index to assess left ventricular systolic function in patients with heart failure.