High B-type natriuretic peptide is often referred to as BNP, and its elevation indicates the presence of heart failure. Its elevation is proportional to the severity of heart failure, and is sensitive to the diagnosis and determination of the degree of heart failure. In normal people, a BNP level of less than 100 pg/ml and more than 400 pg/ml is considered to have a high probability of heart failure. Between 100 and 400 pg/ml, it is necessary to determine which type of disease is responsible according to clinical manifestations or other relevant tests. The measurement of the project is also very helpful for the evaluation of the effect of heart failure medication. Some people do not show obvious symptoms after treatment, but the test is very sensitive to determine the effect of treatment during the period, and the specificity of BNP is relatively poor. When it is obviously elevated, it is not necessarily due to heart failure, but may be due to severe renal insufficiency or serious infection, and after shock, it may also lead to abnormal elevation of BNP, which is definitely abnormal.