Blood tests are an important tool for diagnosing heart failure. Doctors can also use blood tests to monitor treatment progress and check for potential complications.

Heart failure occurs when the heart cannot pump enough blood to meet the body’s needs. Several conditions, including coronary artery disease, high blood pressure, and diabetes, can cause heart failure.

Doctors may order blood tests for people who have suspected heart failure.

This article outlines different types of blood tests and what to expect from the procedure. It also discusses results and other diagnostic tests doctors may use.

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A blood test can indicate whether someone is experiencing heart failure and help determine the cause. It can also check the function of other organs in the body. Different blood tests look for different things.

Blood tests to assess the heart measure certain blood proteins, hormones, and electrolyte levels. These markers can indicate whether the heart is functioning properly.

Doctors use the results of these blood tests to determine the best course of treatment. Comparing the results from several tests also helps doctors monitor the effects of treatment.

In people with suspected heart failure, doctors may order the following blood tests:

Basic metabolic panel (BMP)

A BMP is a comprehensive set of tests that can provide insights into a person’s overall health. It checks kidney function and measures the levels of glucose, electrolytes, calcium, and other naturally occurring chemicals in the blood. Learn more about a BMP test.

B-type natriuretic peptide (BNP)

A BNP test is a valuable tool for diagnosing heart failure. It measures the amount of BNP in the blood, indicating how well the heart functions. If a test reveals a rise in BNP, this can be an early warning sign of heart failure, and doctors will want to investigate further. Learn more about a BNP test.


The body releases the protein troponin when the heart muscle is damaged. Troponin levels are an important indicator of cardiac health. The test helps identify those at risk of developing heart disease and provides a warning sign of impending cardiac events.

A healthcare professional usually performs blood tests in a doctor’s office. This person is often a phlebotomist.

Drawing blood typically involves the following steps:

  • The professional cleans an area of the arm with an antiseptic.
  • They place a tourniquet around the person’s arm to ensure the blood flows to the chosen vein, making access easier.
  • They insert a needle into the vein and collect a small amount of blood into one or more tubes.
  • After removing the needle, they apply pressure to the area before placing a small bandage over the site.

The process typically takes a few minutes. It can sometimes take longer if the healthcare professional cannot find a vein easily. This can happen for various reasons, such as when a person is dehydrated.

Does it hurt?

Typically, people feel a small, sharp prick when the needle enters the skin, but it should not cause much pain. A person who fears needles may wish to inform the healthcare professional, who may offer to numb the area before performing the test.

People may develop a small bruise over the needle insertion area, but this should resolve itself over the next few days.

Learn more about blood tests.

Blood test results may be ready on the same day or take several days or weeks.

Normal ranges can vary based on age, sex, and health status.

In a healthy person, BNP levels are usually less than 100 picograms per milliliter (pg/ml). If a person has a high BNP, doctors usually order more tests to investigate further. BNP levels tend to increase with age and are usually higher in females than males.

Lab results usually show measurements of substances in a person’s blood alongside the normal ranges for those substances. If a person’s measurements fall outside the normal range, a doctor will likely order more tests to help with diagnosis.

Learn more about heart failure.

Other diagnostic tests doctors use for heart failure include:

  • Cardiac catheterization: Using a dye, this process can reveal blockages in the coronary arteries.
  • Echocardiography: This allows doctors to identify a person’s heart rhythm and if they have previously had a heart attack.
  • Electrocardiogram (EKG or ECG): This can show doctors the thickness of the heart muscle and how well the heart pumps blood.
  • Exercise stress test: This measures how well a person’s heart works under stress.
  • MRI: This shows narrowed or blocked arteries and provides images of the heart’s structure.
  • Radionuclide ventriculography: This allows doctors to see how well the heart’s chambers are working and assess the heart’s blood supply.
  • X-ray: This can help doctors identify enlargements of the heart or fluid in the lungs.

Find cardiovascular health information in our dedicated hub.

Heart failure is a serious condition where the heart cannot pump blood around the body efficiently.

Doctors use several blood tests to assess heart function, including BNP and BMP. Drawing blood is quick, and results are often available within a few days.

Abnormal blood test results may indicate a strain on the heart or other organs, such as the kidneys and liver. Doctors usually order further tests to help with diagnosis.

Early diagnosis and treatment of heart failure are essential to reduce the risk of long-term complications.