Cardiac function grading includes American New York Heart Association NYHA grading, Killip grading and so on, the meaning of IV grade of each grading is different, but all of them suggest that the heart function is in a serious bad state. 1. American New York Heart Association NYHA classification IV: this classification is used for the evaluation of chronic heart failure, IV suggests that the heart failure is serious, this time is often accompanied by dyspnea at rest, sitting breathing and other symptoms. 2. Killip classification IV: This classification is used for the evaluation of acute heart failure, in this period, due to severe heart failure, cardiogenic shock has already appeared, most of the cardiogenic shock manifestations such as hypotension, and may be accompanied by cyanosis, oliguria, sweating. Regardless of the cardiac function classification, Class IV is serious and requires immediate hospitalization.