The correct name for n-terminal brain natriuretic principle is amino-terminal brain natriuretic peptide precursor, or NT-proBNP for short, and a maximum of 35,000 pg/ml suggests severe heart failure. NT-proBNP is a product of the metabolism of B-type natriuretic peptide proteins (proBNP) in the body and is commonly used to assess the function of the heart, with a normal range of <125 pg/ml. a number of non-heart failure factors, such as atrial fibrillation, sepsis, burns, strokes, lung infections, pulmonary embolisms, and severely depressed renal function, can lead to mildly elevated NT-proBNP. When NT-proBNP is used to determine heart failure, there are different criteria according to different ages. <300pg/ml can exclude heart failure; >450pg/ml suggests heart failure in people younger than 50 years old; >900pg/ml suggests heart failure in people aged 50-75 years old; and >1,800pg/ml suggests heart failure in people aged 75 years old or older. For NT-proBNP35000pg/ml suggests severe heart failure, the condition is more serious, the patient’s life is in danger at any time, need to consult a doctor in time, by professional doctors for individualized treatment.