Podcast Summary: Dr. Chapa’s Clinical Pearls

Episode: BNP and proBNP in PreE

Date: September 17, 2025

Overview

This episode addresses the clinical interpretation and significance of BNP (B-type Natriuretic Peptide) and proBNP levels in patients with preeclampsia, focusing on a real-world postpartum case. Dr. Chapa gives practical insights on how to understand and manage elevated BNP/proBNP values in the context of preeclampsia with severe features versus primary cardiac complications, debunking misconceptions and offering advice for front-line clinicians.

Case Introduction & Context

[00:40-07:00]

• Case Description:

  • 7 days postpartum patient admitted for severe headache and discovered to have severe-range hypertension.
  • No prior hypertensive disorder during pregnancy.
  • ER staff ordered CT head scan (normal) and labs including BNP and proBNP due to concern for cardiac issues.

• Clinical Dilemma:

  • BNP of 800 (normal ~100 in pregnancy), and proBNP of 1800 (normal up to 200-250).
  • Clinical concern: “Is this impending heart failure or a cardiac event?”
  • Patient lacked classic heart failure symptoms (no shortness of breath, chest pain, or EKG changes).

Key Discussion Points and Insights

1. BNP and proBNP: Functions and Differences

[03:00, 08:00, 12:00]

• BNP is an acute marker, rises and normalizes faster. proBNP remains elevated longer and is a marker of more chronic cardiac strain.

• Both are structurally different but offer similar clinical information regarding cardiac strain.

• “BNP is more of an acute marker… proBNP is more of a chronic finding.” (Dr. Chapa, 03:15)

• In pregnancy:

  • BNP is typically ≤100.
  • proBNP can be up to 200-250.

• Values exceeding these, especially in the setting of preeclampsia with severe features, reflect significant cardiac strain but not necessarily heart failure.

2. When Are BNP/proBNP Elevated in Obstetrics?

[07:50, 11:40, 17:10]

• BNP/proBNP can be elevated in:
  • Heart failure (with classic symptoms).
  • Pulmonary embolism.
  • Infections with cardiac involvement.
  • Crucially: preeclampsia with severe features due to “side-effect of heart strain when the peripheral vasculature is clamped up.” (Dr. Chapa, 05:15)
• "While it can be a marker of heart failure, it doesn't always mean heart failure." (Dr. Chapa, 07:30)
• Postpartum, especially de novo preeclampsia, patients are sicker and exhibit higher BNP/proBNP elevations.

3. Management and Clinical Decision-Making

[15:00, 19:00]

• Emphasis on interpreting BNP/proBNP in the clinical context:

  • Absence of symptoms of heart failure means the elevated labs likely reflect preeclampsia’s vascular effects, not acute cardiomyopathy.
  • Cardiology consult is not automatically indicated—unless clinical symptoms arise.

• Troponin and EKG: If normal, further supports absence of acute MI/heart failure.

• Baseline echocardiogram can be considered for future comparison but is not required solely based on elevated BNP/proBNP if the patient is asymptomatic.

• Memorable quote:

  • “There's nothing wrong with getting a cardiac echo on a patient like this… not because she's symptomatic… but as a baseline… so that if something happens down the road, we can compare it later as a follow up study.” (Dr. Chapa, 17:30)

4. Laboratory Trends and Follow-up

[07:30, 12:20, 21:40, 23:40]

• Expectation management:

  • BNP may normalize within days to weeks as vasospasm resolves.
  • proBNP may take multiple weeks to trend down.
  • Outpatient trending is reasonable when levels are markedly elevated.

• “Even though the patient deescalates with anti-hypertensives and magnesium… it may take weeks for the BNP or proBNP to normalize.” (Dr. Chapa, 07:50)

5. BNP/proBNP as Disease Continuum Markers

[21:50–24:20]

• BNP/proBNP levels represent a continuum:
  • Normal in normotensive pregnancy.
  • “On the higher end of normal” in gestational hypertension and non-severe preeclampsia.
  • Significantly higher in preeclampsia with severe features; “several fold or several magnitude abnormal.” (Dr. Chapa, 24:05)
• Potential (not currently endorsed by ACOG/SMFM) as predictive biomarkers for disease progression.

Clinical Pearls & Guidance

Summary Table

| Clinical Scenario | Typical BNP (pg/mL) | Typical proBNP (pg/mL) | Clinical Relevance | |-----------------------------|---------------------|------------------------|------------------------------| | Normal Pregnancy | <100 | <200–250 | Normal | | Gestational Hypertension | High-normal | High-normal | Usually normal usage | | PreEclampsia w/o Severe | High-normal | High-normal | Slight increase possible | | PreEclampsia w/ Severe | Hundreds/1000s | Hundreds/1000s | Significant cardiac strain |

Notable Quotes & Memorable Moments

“If it looks like a duck, it quacks like a duck… you got high blood pressure, you're seven days postpartum and you got a headache – chances are you got preeclampsia with severe features.”
— Dr. Chapa, [02:30]

“These are very good, very sensitive tests to look for cardiac strain… but it's not specific to heart failure since it can rise in something like preeclampsia with severe features.”
— Dr. Chapa, [12:08]

“BNP and proBNP… can be off the chart. We're talking several fold or several magnitude abnormal.”
— Dr. Chapa, [24:05]

“Beta type—dang it. I did it again. B type, not beta. B type Natriuretic Peptide is definitely elevated in preeclampsia with severe features without overt heart failure.”
— Dr. Chapa, [24:19]

Conclusion / Clinical Take-Home

• Elevated BNP/proBNP in postpartum patients with preeclampsia and severe features is an expected marker of cardiac strain secondary to vascular changes, not necessarily heart failure.
• Always interpret in clinical context: absence of heart failure symptoms makes acute cardiac pathology less likely.
• Cardiology involvement and echo can be considered for baseline or if clinical status changes.
• Outpatient follow-up and trending are often necessary due to delayed normalization.
• Remember:

  “This is just a reflection of normal and expected cardiac strain and the subclinical dysfunction that happens with systemic peripheral vascular constriction, i.e. postpartum preeclampsia with severe features.”
  — Dr. Chapa, [24:09]

For more practical, no-nonsense clinical wisdom, stay tuned for the next episode of Dr. Chapa’s Clinical Pearls!