Heart Failure Index or NT-proBNP. 48 years old NT-proBNP 13,000pg/ml is serious. NT-proBNP is an important indicator for diagnosing acute heart failure and assessing severity. The cut-off value for NT-proBNP to diagnose acute heart failure varies by age. Less than 50 years old, the cut-off value of NT-proBNP is 450pg/ml, 50-75 years old, the cut-off value of NT-proBNP is 900pg/ml, and more than 75 years old, the cut-off value of NT-proBNP is 1,800pg/ml. 48 years old NT-proBNP 13,000pg/ml is already much larger than its cut-off value of 900pg/ml. And it has been shown that NT-proBNP greater than 5000pg/ml has an increased risk of death within 75 days. Therefore, NT-proBNP 13000pg/ml at age 48 is serious and requires immediate hospitalization. NT-proBNP13000pg/ml is very serious and needs to go to a regular hospital immediately and be treated by a professional doctor to avoid delaying the condition and affecting the prognosis.