What Tests Are Used to Diagnose and Evaluate Heart Failure?

Heart failure is not diagnosed or evaluated with a single test. Instead, your care team uses a combination of physical exams, blood work, and imaging studies to piece together a complete picture of how your heart is functioning, what might be causing the problem, and how it is affecting the rest of your body ^[1].

Because every patient is different, testing is highly individualized based on your specific symptoms, medical history, and risks. Going through a large battery of tests can feel overwhelming, but these results are essential for creating a safe and effective treatment plan.

When to Seek Immediate Help: If you experience severe or rapidly worsening shortness of breath (especially at rest), chest pain, fainting, confusion, or blue lips, do not wait for routine testing. Contact emergency services or follow your care team’s emergency action plan immediately.

The Initial Heart Failure Evaluation

When you are first evaluated for suspected heart failure, you will typically undergo a common set of initial tests. These help support the diagnosis, evaluate your heart’s structure, and ensure treatments will be safe ^[2].

Medical History and Physical Examination

Your doctor will start by listening to your symptoms and examining you. They will look for signs of fluid buildup (congestion), such as swelling in your legs, fluid in your lungs, or a sudden increase in weight ^[1]. They will ask about your ability to exercise, whether you wake up gasping for air, your family history, and any past exposure to chemotherapy or alcohol.

Echocardiogram (Echo)

An echocardiogram is an ultrasound of your heart and is a central part of any heart failure evaluation ^[2]. It is a painless test that uses sound waves to create moving pictures of your heart, providing a wealth of information:

• Ejection Fraction (EF): This is the percentage of blood pumped out of your main pumping chamber (the left ventricle) with each heartbeat ^[3]. Heart failure can occur with a reduced EF, mildly reduced EF, or a preserved (normal) EF. Right-ventricular function is also measured separately ^[4].
• Chamber Size: It shows whether the chambers of your heart have become enlarged or if the muscle has thickened ^[5].
• Valve Function: It looks for valves that are too narrow or that leak (called regurgitation) ^[6].
• Filling Patterns: It measures how well the heart muscle relaxes and fills with blood between beats, known as diastolic function ^[7].
• Pulmonary Pressures: It can estimate the blood pressure within your lungs to check for pulmonary hypertension (high blood pressure in the lungs) and look at the veins returning to your heart to help assess pressures ^[8].

Blood Tests

Blood tests provide vital clues and help monitor your safety during treatment.

• BNP or NT-proBNP: These are natriuretic peptides, proteins your heart releases when it is stretched. High levels support a heart failure diagnosis, but they must be interpreted in context. Factors like kidney disease or atrial fibrillation can raise these levels, while obesity can artificially lower them, and a normal level does not always completely rule out heart failure ^[2][9][10].
• Kidney Function and Electrolytes: Tests measuring creatinine, blood urea nitrogen (BUN), sodium, and potassium are critical. Heart failure and its treatments directly affect the kidneys, so these markers are monitored closely to ensure your safety ^[11][12][13].
• Complete Blood Count (CBC) and Iron Studies: Anemia (defined by low hemoglobin or hematocrit) and iron deficiency are very common in heart failure and can severely limit your energy ^[14][15]. Tests for ferritin and transferrin saturation help identify iron deficiency, though whether you need iron supplementation depends on your specific clinical picture ^[16].
• Liver and Thyroid Tests: Initial evaluations often include checking liver enzymes and thyroid function, as an overactive or underactive thyroid can contribute to heart problems, and heart failure can cause fluid to back up into the liver ^[2].

Urine Testing

A urine test checking the urine albumin-to-creatinine ratio assesses if protein (albumin) is leaking into the urine. This indicates potential kidney damage, which is a different measurement from how well your kidneys are filtering blood ^[17].

Electrocardiogram (ECG) and Chest X-ray

• Electrocardiogram (ECG or EKG): A quick, painless test recording the electrical signals in your heart. It may suggest a prior heart attack, abnormal rhythm, or thickened muscle, though it usually cannot prove these on its own ^[2].
• Chest X-ray: This imaging may show an enlarged heart silhouette or fluid in the lungs, but a normal X-ray does not rule out heart failure ^[2].

Additional Specialized Testing

If initial tests do not pinpoint the cause of your heart failure, or if you need advanced treatments, your care team may order specific, individualized tests.

• Coronary Imaging: To check for blocked arteries, doctors may use a CT angiography (which uses contrast dye and radiation) or an invasive coronary angiogram (cardiac catheterization) ^[18].
• Stress Testing and CPET: A standard stress test checks for reduced blood flow to the heart. Cardiopulmonary Exercise Testing (CPET) is a specialized version that also measures your breathing and oxygen use to objectively evaluate exercise limits and help plan advanced therapies like a transplant ^[19][20].
• Cardiac MRI: A detailed scan that can detect scar tissue from past heart attacks or specific types of heart muscle inflammation (myocarditis) ^[21].
• Right-Heart Catheterization: An invasive procedure where a catheter is threaded into the right side of the heart to directly measure pressures in the heart and lungs ^[22].
• Rhythm Monitoring (Holter Monitor): A portable ECG worn for days or weeks to continuously record heart rhythms if you experience unexplained fainting or palpitations ^[23].
• Sleep-Apnea Testing: Sleep studies identify the type and severity of sleep-disordered breathing. Depending on whether you have obstructive or central sleep apnea, your team will customize treatment, as some breathing devices are not safe for all heart failure patients ^[24].
• Genetic Testing: If you have an unexplained or inherited heart muscle disease (cardiomyopathy), genetic counseling and testing can help understand your risks and guide family screening ^[25].

Summary of Heart Failure Tests