Evaluation of normal cardiac function standards generally have left ventricular ejection fraction, heart rate, B-type natriuretic peptide. 1. The left ventricular ejection fraction is the EF value, the normal EF value is more than 55%, if the EF value is less than 50% suggests that the patient’s cardiac insufficiency, the EF value is less than 30% suggests that the severe cardiac insufficiency. 2. Heart rate refers to the number of heartbeats per minute, and the normal value is 60-100 beats per minute. Generally, the heart rate of women is faster than that of men of the same age, and the heart rate of athletes is slower than that of ordinary people of the same age, which is a normal phenomenon. 3. B-type natriuretic peptide is BNP, generally normal heart function BNP is less than 100pg/ml, heart failure patients BNP is often greater than 400pg/ml, if the BNP between 100 and 400, suggesting that the patient has right heart failure or pulmonary embolism.