Is it possible to measure atrial natriuretic peptide (ANP) in a clinical setting?

Can ANP Be Measured in Clinical Practice?

While ANP can technically be measured using radioimmunoassay methods, it is not routinely available or recommended for clinical use—instead, measure BNP or NT-proBNP, which are the established natriuretic peptides for diagnosing and managing heart failure in clinical settings.

Why ANP Is Not Used Clinically

ANP (atrial natriuretic peptide) exists and can be measured in research settings 1, 2, but it has been superseded by BNP and NT-proBNP for practical clinical applications. The guidelines consistently focus on BNP and NT-proBNP because:

• Most clinical data and validation studies use BNP or NT-proBNP, not ANP 2
• ANP assays are not standardized or widely available in clinical laboratories
• BNP and NT-proBNP have established diagnostic thresholds with extensive evidence supporting their use 3, 2

What You Should Measure Instead

For Acute Heart Failure Diagnosis

Measure BNP or NT-proBNP when evaluating patients with acute dyspnea or suspected heart failure 3, 2:

• BNP thresholds:

  • <100 pg/mL: Rules out acute HF (high sensitivity ~90%) 2, 4

  • 500 pg/mL: Supports acute HF diagnosis 3

• NT-proBNP thresholds:

  • <300 pg/mL: Rules out acute HF 2
  • Age-adjusted rule-in values: 450 pg/mL (<50 years), 900 pg/mL (50-75 years), 1800 pg/mL (>75 years) 2

Key Adjustments Required

• Obesity: Use 50% lower cut-offs (BNP ~55 pg/mL for BMI >35) 2
• Renal impairment: Use higher thresholds (BNP 200-225 pg/mL for GFR <60) 2

Clinical Context for ANP Measurement

The evidence shows that plasma ANP levels are elevated in atrial fibrillation and heart failure 1, and ANP decreases rapidly after restoration of sinus rhythm 1. However, this information is primarily of research interest. In clinical practice:

• Mid-regional proANP (MRproANP) at <120 pmol/L shows promise with sensitivity approaching 1.0 4, but it remains investigational and not widely available
• BNP and NT-proBNP have no significant difference in diagnostic accuracy 4, making either acceptable for clinical use

Bottom Line

Order BNP or NT-proBNP, not ANP. These are the validated, guideline-recommended natriuretic peptides with established cut-offs, widespread laboratory availability, and robust evidence for diagnosis and risk stratification in heart failure 3, 2, 5. ANP measurement remains a research tool without clinical utility or availability in standard practice.