NT-proBNP of 134 pg/mL: Normal Value
An NT-proBNP level of 134 pg/mL is normal and effectively rules out heart failure, as it falls well below the diagnostic threshold of 300 pg/mL used to exclude heart failure in non-acute settings. 1
Interpretation Based on Clinical Context
For Non-Acute Presentations
- The European Society of Cardiology establishes that NT-proBNP <300 pg/mL in non-acute settings has a 98% negative predictive value for heart failure, making heart failure highly unlikely 1
- Your patient's value of 134 pg/mL is less than half this exclusion threshold 1
Age-Adjusted Normal Ranges
- For patients aged 45-59 years: normal is <164 pg/mL for females and <100 pg/mL for males 1
- For patients >60 years: normal is <225 pg/mL for females and <98 pg/mL for males 1
- Your patient's value of 134 pg/mL falls within normal limits for all age groups 1
Clinical Decision Algorithm
If symptoms suggest cardiac disease despite normal NT-proBNP:
- Proceed directly to echocardiography, as the European Society of Cardiology recommends that when NT-proBNP is <300 pg/mL but the ECG is abnormal, further cardiac imaging is warranted 1
- Consider alternative diagnoses including valvular disease, constrictive pericarditis, or heart failure with preserved ejection fraction (HFpEF), where NT-proBNP may be less elevated 1
If patient is asymptomatic or symptoms are non-cardiac:
- No further cardiac workup is needed based on this NT-proBNP value alone 1
- The American College of Cardiology notes that this level provides strong reassurance against significant cardiac dysfunction 1
Important Caveats
Conditions That May Lower NT-proBNP
- Obesity significantly reduces NT-proBNP levels through increased clearance and suppression of pro-BNP synthesis, potentially masking underlying cardiac dysfunction 1
- Male sex is associated with consistently lower baseline NT-proBNP values due to androgen suppression 1
When Normal NT-proBNP Does NOT Rule Out Disease
- Acute coronary syndromes in the first few hours of presentation may not yet show NT-proBNP elevation 1
- Flash pulmonary edema or acute mitral regurgitation may present before significant NT-proBNP rise 1
- Constrictive pericarditis typically shows normal or minimally elevated NT-proBNP despite significant cardiac limitation 2
Prognostic Significance
- A normal NT-proBNP level like 134 pg/mL is associated with excellent long-term cardiovascular prognosis 3
- In stable coronary disease patients, those with NT-proBNP in the lowest quartile have significantly lower mortality risk compared to higher quartiles 3
- This value suggests low perioperative cardiovascular risk if surgery is being considered, as levels <100 pg/mL define a low-risk group 4