From the Guidelines
Significance of B-type Natriuretic Peptide (BNP) Levels
BNP is a crucial biomarker for diagnosing and managing heart failure, with elevated levels indicating increased ventricular stretch and potential cardiac dysfunction 1.
- Diagnostic Thresholds: BNP levels above 100 pg/mL are considered abnormal, while levels above 400 pg/mL are associated with severe heart failure 2.
- Clinical Interpretation: The diagnostic strength of natriuretic peptides lies in their high sensitivity for ruling out heart failure; however, as the value increases, heart failure becomes more likely 1.
- Factors Influencing BNP Levels: Age, sex, and comorbidities such as cardiac, pulmonary, and renal disease can influence BNP levels, making cautious interpretation essential, especially in the presence of confounders 1.
- Prognostic Value: Elevated BNP levels are associated with increased morbidity and mortality in patients with heart failure, and can be used to establish prognosis or disease severity in outpatients with chronic heart failure 3.
- Guiding Therapy: BNP- or NT-proBNP–guided therapy can be useful to achieve optimal dosing of medical therapy in select clinically euvolemic outpatients in structured management programs 3.
From the Research
Significance of B-type Natriuretic Peptide (BNP) Levels
- BNP is a biomarker used to assess cardiac dysfunction and heart failure, with increased levels indicating a higher risk of recurring myocardial infarction, heart failure, and death 4.
- BNP and its inactive N-terminal fragment, NT-proBNP, are serum biomarkers that play a key role in the management of heart failure, with elevated levels closely associated with the pathophysiological mechanisms underlying heart failure 5.
- BNP levels can be used to guide therapy in heart failure and left ventricular dysfunction, with excellent negative predictive value for left ventricular dysfunction and heart failure 4.
Clinical Utility of BNP
- BNP measurements have been investigated for their clinical utility in the diagnosis, prognostic stratification, monitoring, and guiding therapy of patients with heart failure 5.
- BNP has been used as a criterion for enrollment in randomized trials evaluating the efficacy of new therapeutic strategies for heart failure 5.
- BNP levels can be used to assess the severity of ventricular dysfunction and heart failure, and as a prognostic predictor, regardless of the primary cause of the condition 4.
Limitations and Pitfalls of BNP Interpretation
- BNP is a nonspecific biomarker of cardiac dysfunction, requiring specific diagnostic tools such as echocardiography to define the actual abnormality 4.
- The use of BNP is still limited in clinical practice due to the controversial aspect of its use in different clinical settings 5.
- Several factors can overestimate or underestimate BNP values, including renal dysfunction, age, female sex, atrial fibrillation, inflammation, hyperthyroidism, use of sacubitril/valsartan, and macro-proBNPemia 6.
- Clinicians should be aware of the pitfalls of interpreting BNP values to ensure accurate diagnosis and management of heart failure patients 6.
BNP Beyond Heart Failure
- BNP levels can increase in other cardiovascular disease states, including ischemia, arrhythmias, fibrosis, cardiac hypertrophy, and coronary endothelial dysfunction 7.
- Moderate elevations in BNP levels have been associated with an increased risk of future cardiovascular events, including heart failure and atrial fibrillation 7.
- BNP may represent a final common pathway for many cardiovascular pathologic states, and can be used as a biomarker for non-HF mechanisms, preclinical disease, and other pathologic states of myocardial disease 7.