Congestive Heart Failure (CHF)

Congestive heart failure (CHF) happens when the heart cannot pump enough blood to meet the body’s needs. Lab tests help confirm or rule in heart-failure physiology, identify causes or triggers, and monitor safety while you and your clinician manage care.

A practical plan usually combines a natriuretic peptide (NT-proBNP or BNP) with electrolytes and kidney function, adds tests that uncover contributors (anemia, thyroid imbalance, iron deficiency), and uses troponin when symptoms suggest acute heart strain. These labs support screening in symptomatic people, diagnostic work-ups, ... See more

Signs, Symptoms & Related Situations

Fluid & breathing: shortness of breath with activity or lying flat, waking at night breathless, persistent cough, swelling in legs/ankles, rapid weight gain from fluid
Fatigue & exercise: low stamina, lightheadedness, reduced exercise tolerance
Heart sensations: palpitations, irregular heartbeat
Contributors/contexts: recent viral illness, high blood pressure, heart attack, alcohol excess, high-salt intake, medication changes (diuretics, ACEi/ARB/ARNI, MRAs), arrhythmias
Urgent care now: new or crushing chest pain, severe breathlessness at rest, fainting, confusion, pink frothy sputum, or one-sided weakness

Why These Tests Matter

What testing can do

Signal cardiac wall stress (NT-proBNP/BNP) to help differentiate heart vs. non-cardiac shortness of breath
Guide treatment safety by tracking kidney function and electrolytes during diuretics and other heart-failure medications
Reveal contributors such as anemia, thyroid disease, or iron deficiency, and track overall risk (glucose/A1c, lipids)

What testing cannot do

Diagnose blocked arteries or measure ejection fraction—imaging and ECGs are still needed
Replace a clinician’s judgment when symptoms are severe or rapidly changing
Predict exact outcomes from a single value; trends matter most

What These Tests Measure (at a glance)

NT-proBNP or BNP (blood): peptides released with heart-wall stretch; higher values support heart-failure physiology and help track response. Caveats: levels can be lower in obesity and higher in kidney disease or atrial fibrillation—interpret in context.
High-sensitivity Troponin (hs-cTn): detects heart-muscle injury; used when symptoms suggest acute coronary syndrome or decompensation.
Comprehensive Metabolic Panel (CMP) & Electrolytes: sodium, potassium, chloride, CO2 (bicarbonate), creatinine/eGFR, BUN, AST/ALT, albumin—essential for medication safety and fluid status.
Magnesium & Phosphorus: rhythm stability and diuretic effects.
CBC (Complete Blood Count): screens for anemia or infection that can worsen symptoms.
Iron Studies (Ferritin, Iron, TIBC/Transferrin, % Saturation): detect iron deficiency, common in heart failure.
TSH (± Free T4): checks for thyroid dysfunction that can mimic or worsen heart failure.
Urinalysis & Urine Albumin-to-Creatinine Ratio (ACR): kidney health and vascular risk context.
Glucose/A1c & Lipids (± ApoB, Lp[a]): cardiometabolic risk that influences long-term outcomes.
Medication-specific labs (as directed):
- Diuretics: electrolytes (Na/K/Mg), creatinine/eGFR
- ACEi/ARB/ARNI & MRAs (spironolactone/eplerenone): potassium, creatinine/eGFR
- Digoxin (if used): serum digoxin level with renal function and potassium
- Anticoagulants (if used): PT/INR or drug-specific assays per clinician

Quick Build Guide

Situation	Start with	Add if needed
New/worsening shortness of breath	NT-proBNP/BNP, CMP/electrolytes, CBC	hs-Troponin (symptom-driven), TSH, iron studies
Known CHF, routine monitoring	CMP/electrolytes, NT-proBNP/BNP trend	Magnesium, ACR/urinalysis, A1c, lipids
Medication check-in (diuretics, ACEi/ARB/ARNI, MRA)	CMP/electrolytes (K/Na/Cr/eGFR), magnesium	Digoxin level (if on digoxin)
Fatigue/low exercise capacity	CBC, iron studies, TSH	Vitamin B12/folate (contextual)

How the Testing Process Works

Select the right panel: choose a natriuretic peptide (NT-proBNP or BNP) plus CMP/electrolytes; add tests based on symptoms and medications.
Prepare for collection: fasting is usually not required; follow any instructions on your order and list current medications/supplements.
Get your draw: visit a nearby patient service center; most results post within a few days.
Review with your clinician: combine labs with symptoms, exam, blood pressure, ECG, and imaging (echo) to confirm next steps.
Set a cadence: recheck markers on a schedule aligned with medication changes and clinical status.

Interpreting Results (General Guidance)

Natriuretic peptides: rising values often reflect worsening congestion; falling values may signal improvement. Interpret with body size, rhythm (AF), and kidney function.
Electrolytes & kidney function: watch for low sodium, high/low potassium, or rising creatinine—especially after medication changes.
Troponin: even small elevations merit clinical review; acute patterns require urgent evaluation.
Anemia/iron/thyroid: correcting contributors can improve stamina; decisions belong with your clinician.
Always interpret results with a qualified healthcare professional; do not start or stop medications based on labs alone.

Choosing Panels vs. Individual Tests

Symptom triage: NT-proBNP/BNP + CMP/electrolytes + CBC (± hs-Troponin)
Stable CHF follow-up: CMP/electrolytes + NT-proBNP/BNP trend (± magnesium, ACR)
Contributor check: CBC + Iron Studies + TSH
Risk context: A1c/Glucose + Lipid Panel (± ApoB, Lp[a])
Medication safety: targeted electrolytes/renal function (and digoxin level if applicable)

FAQs

Do I need to fast for CHF labs?
Usually no. Follow the instructions on your order.

Which is better—BNP or NT-proBNP?
Both reflect heart-wall stress. Your clinician will choose based on local practice and your kidney function/age.

Can kidney disease change results?
Yes. Kidney dysfunction can raise natriuretic peptide levels and affect electrolytes; interpretation adjusts for this.

My BNP fell—does that mean I’m cured?
Lower numbers often track improvement, but symptoms and exams still guide care. Continue regular follow-up.

Why check iron and thyroid?
Iron deficiency, anemia, and thyroid disorders can worsen fatigue and shortness of breath in CHF.

How often should I test?
It depends on symptoms and treatment changes. Many people test more often during medication adjustments, then less once stable.

Related Categories & Key Tests

Heart & Cardiovascular Tests Hub
Cardiovascular Disease (CVD) Tests • Cholesterol Tests • Diabetes & Insulin Resistance • Kidney Health • Electrolytes & Hydration • Thyroid Testing
Key Tests: NT-proBNP/BNP • CMP/Electrolytes (Na/K/Cl/CO2, BUN/Creatinine/eGFR, AST/ALT, Albumin) • hs-Troponin • Magnesium • CBC • Iron Studies (Ferritin/Iron/TIBC/Transferrin, %Sat) • TSH (± Free T4) • Urinalysis & ACR • A1c/Glucose • Lipid Panel • Digoxin level (if used)

References

American College of Cardiology/American Heart Association — Heart failure evaluation and monitoring guidance.
Heart Failure Society of America — Biomarker use in heart failure.
KDIGO — Kidney disease and albumin-creatinine testing recommendations.
AHA/CDC — Cardiometabolic risk and inflammation resources.
Clinical reviews on natriuretic peptides, troponin in acute and chronic heart failure, and medication-related electrolyte monitoring.

Available Tests & Panels

Your Congestive Heart Failure (CHF) Tests menu is pre-populated in the Ulta Lab Tests system. Start with NT-proBNP/BNP and CMP/electrolytes, add CBC, troponin (when symptoms warrant), and contributor tests (iron studies, TSH). Include kidney markers for medication safety and consider A1c/lipids for long-term risk. Review results with your clinician to personalize follow-up.

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Congestive Heart Failure Symptoms & Laboratory Testing

Congestive Heart Failure is also known as CHF or heart failure. Whatever you call it, this condition is one where the human heart is unable to pump blood with the efficiency that it once did. This means that blood, as well as other various fluids, start backing up inside the body. The effect is particularly pronounced in the feet, hands, lungs, and liver.

The human heart has two different sides to it, as well as four different chambers. The right side is what takes in blood depleted of oxygen from throughout the body, sending it into the lungs. Once the lungs replenish the oxygen in the blood, it’s the left side that pumps this fresh blood back out into the overall body.

Congestive Heart Failure is a very serious condition, one that is progressive. It’s often chronic, and it can threaten your life. It might impact the left side of the heart, the right side, or even both sides. Those with CHF have lowered amounts of nutrients and ... See more

CHF can happen for several different reasons. Most frequently, the heart undergoes damage, which might be hypertension/high blood pressure, prior heart attacks, or even cardiomyopathy, which is direct damage right to the actual heart muscle. Congestive Heart Failure can also happen if there is any damage to the heart valves or pericardium scarring to the membrane that physically surrounds the human heart. On rare occasions, CHF happens if the heart must start beating with more force than is typical, as which can happen with hyperthyroidism, where it simply can’t keep up with the current demand. Congestive Heart Failure risks are elevated among those with diabetes, the overweight and obese, smokers, and anyone who abuses cocaine and/or alcohol.

CHF is very common in elderly individuals since the human heart tends to lose efficiency with age. The National Heart, Lung and Blood Institute has estimates showing that between 5.5 and 6 million Americans have heart failure at any given time. For those older than 65, it’s among the most frequent reasons for hospitalization.

Symptoms/Signs

When blood backs up starting from the heart’s right side, then Congestive Heart Failure symptoms typically start with ankles and legs swelling in ways that get worse if a person stands up but gets better if they lie down. If blood starts backing up from the heart’s left side, then it moves into the lungs, resulting in coughing or breathing, particularly during periods of lying down flat or exercise, even if it’s just walking up a set of stairs. Many individuals that suffer heart failure have demonstrated symptoms of blood that’s backing up simultaneously on both sides of the heart.

On top of shortness of breath and edema/swelling, other symptoms can include the following:

Rapid pulse, heart palpitations
Fatigue, weakness
Less stamina, lower ability to do physical exercise
Wheezing, coughing
Sudden gains of weight
Lost appetite
Nausea

Laboratory testing can include the following:

BNP or N-terminal pro-BNP: BNP stands for B-type natriuretic peptide, which is a measurement of concentrations of a specific hormone the left ventricle produces. Given its role as the heart’s primary pumping chamber, the left ventricle’s production of BNP helps doctors both diagnose and grade how serious heart failure is.

Metabolic Panel: This looks for things like liver disease, electrolyte imbalances, and kidney failure, given how many kidney disease symptoms are very similar to the ones of Congestive Heart Failure.

CBC: A complete blood count looks for anemia, which not only has symptoms like CHF but can also contribute to CHF.

Thyroid Testing: Such tests check the thyroid hormone levels in the blood. Heart failure can result from both hyperthyroidism and hypothyroidism, which are respectively too much or too little thyroid hormone.

Two relatively new tests are now available for those already diagnosed with CHF to predict their prognosis. ST2 and Galectin-3 tests both measure protein levels in the blood. If these biomarkers are elevated, they might indicate someone who has heart failure is at a higher risk of complications and requires more assertive levels of treatment.