The normal value of EF in cardiac ultrasound is 50%-70%, and cardiac insufficiency is considered below 50%. Cardiac insufficiency can be categorized as grade 1, 2, 3 or 4 according to the degree of decline of activity endurance, the higher the grade, the more serious the degree and the worse the prognosis. Once cardiac insufficiency is present, it should be strictly prevented from transforming into heart failure. Among the treatment principles of cardiac insufficiency and heart failure, improving blood supply to the heart and preventing ventricular remodeling is one of the more important basic treatment principles. The most representative drugs are angiotensin-converting enzyme inhibitors, including enalapril, fosinopril and so on. A part of patients will have intolerable irritating dry cough after taking this kind of drugs, which can be replaced by angiotensin II receptor blockers, the representative drugs include Irbesartan, Valsartan, etc. Cardiac ultrasound can look at the size of the chambers of the heart in addition to the EF value and is used to diagnose associated myocardial diseases.