From the Guidelines
Elevated BNP levels are primarily caused by heart failure, but can also be attributed to various cardiac and non-cardiac conditions, including acute coronary syndromes, pulmonary embolism, myocarditis, and severe lung diseases, as well as non-cardiac conditions such as kidney dysfunction, sepsis, and advanced age, as outlined in the 2016 ESC guidelines 1. The causes of elevated BNP levels can be categorized into cardiac and non-cardiac conditions. Cardiac conditions that can elevate BNP levels include:
- Heart failure, such as congestive heart failure and heart failure with preserved ejection fraction (HFpEF) or reduced ejection fraction (HFrEF)
- Acute coronary syndromes
- Pulmonary embolism
- Myocarditis
- Left ventricular hypertrophy
- Hypertrophic or restrictive cardiomyopathy
- Valvular heart disease
- Congenital heart disease
- Atrial and ventricular tachyarrhythmias
- Heart contusion
- Cardioversion, ICD shock
- Surgical procedures involving the heart
- Pulmonary hypertension Non-cardiac conditions that can elevate BNP levels include:
- Advanced age
- Ischaemic stroke
- Subarachnoid haemorrhage
- Renal dysfunction
- Liver dysfunction (mainly liver cirrhosis with ascites)
- Paraneoplastic syndrome
- Chronic obstructive pulmonary disease (COPD)
- Severe infections (including pneumonia and sepsis)
- Severe burns
- Anaemia
- Severe metabolic and hormone abnormalities It is essential to consider the patient's overall clinical picture when interpreting BNP results, as levels can be affected by multiple factors simultaneously, and to use the most recent and highest quality guidelines, such as the 2016 ESC guidelines 1, to inform clinical decision-making.
From the Research
Reasons for Elevated BNP
Elevated B-type natriuretic peptide (BNP) levels can be caused by various factors, including:
- Cardiac diseases such as congestive heart failure (CHF), acute coronary syndromes, diastolic dysfunction, atrial fibrillation (AF), amyloidosis, restrictive cardiomyopathy (RCM), and valvular heart disease 2, 3, 4
- Non-cardiac diseases such as pulmonary hypertension, chronic obstructive pulmonary disease, pulmonary embolism, and renal failure 2, 3
- Critical illness such as acute decompensated CHF (ADHF) and sepsis 2, 3
- Age, gender, and body mass index (BMI) can also influence BNP levels 2, 5
Clinical Settings
BNP levels can be elevated in various clinical settings, including:
- Acute coronary syndromes, where BNP can predict death and subsequent development of heart failure 4
- Acute heart failure, where extremely elevated BNP levels are associated with decreased cardiac output, prolonged hospital stay, and increased 6-month all-cause-mortality 6
- Dyspneic patients without heart failure, where independent predictors of elevated BNP levels include a medical history of atrial fibrillation, radiographic cardiomegaly, decreased blood hemoglobin concentration, decreased body mass index, and increased age 5
Interpretation of BNP Levels
It is essential for clinicians to understand how to appropriately interpret BNP levels in light of the comorbidities of individual patients to maximize its clinical utility 2, 3. BNP levels should be considered in conjunction with other clinical variables, such as medical history, physical examination, and laboratory results, to accurately diagnose and manage patients with elevated BNP levels 2, 3, 4, 6, 5