Diagnosis Heart Failure: Blood Tests
The make-up of each person’s blood can offer information about their general health status and their heart health.1 Blood test results provide meaningful clinical findings that help in the diagnosis of certain diseases and conditions, check on organ function, and even assess effectiveness of certain medical treatments.2
Although a blood test by itself is not the only piece of information used to determine whether you have or will develop heart failure, it is an important diagnostic tool. Blood test results that are higher or lower than the normal range may indicate a condition that can place a strain on the heart, kidneys, or liver, which could be caused by heart failure.3
Significant risk factors for heart disease include smoking, high blood pressure, high cholesterol, and diabetes. These conditions can also be evaluated during a physical exam and thorough information gained from blood tests.1
How are blood tests performed?
Blood tests may be performed in a lab or provider’s office.1-2 They are a typical part of a routine exam. Sometimes blood tests are done before you eat for the day, after an 8-12 hour fast. Samples of blood are drawn by a needle from a vein in the arm into test tubes which are then analyzed by a lab for the levels of specific components.2
Key blood tests
Blood test results offer clinicians information about the specific levels of substances in your blood and compare them to the targeted normal range for each one.3 Normal ranges can vary based on age, gender, race, and other factors including certain illnesses.2
Common blood tests include:2
- A complete blood count (CBC)
- Blood chemistry tests
- Blood enzyme tests
- Blood tests to assess the risk of heart failure
A CBC measures red and white blood cells, platelets, hemoglobin, hematocrit, and mean corpuscular volume. These levels are useful in identifying abnormal blood conditions including anemia, infections, clotting problems, blood cancers, and problems with the immune system.2
Blood chemistry tests are often referred to as a basic metabolic panel (BMP). These tests measure different chemicals in the blood, including glucose, electrolytes, including calcium and potassium, as well as kidney function.
Blood enzyme tests evaluate chemical reactions in the blood that can identify a heart attack. Elevated levels of troponin and creatine kinase are indicative of a heart attack.
Blood tests to assess the risk of heart failure include lipoprotein (or lipid) panels which evaluate fats in the blood, including cholesterol. Abnormal levels can be a sign of the presence or risk of heart disease. These tests include:1-2
- Total cholesterol - the total blood cholesterol content
- LDL ("bad") cholesterol – the buildup of fatty deposits, called plaques, which can reduce blood flow and block the arteries.
- HDL ("good") cholesterol – carries away the bad cholesterol and helps decrease blockages.
Triglycerides- a type of fat in your blood that can increase the risk of heart disease.
Other blood tests
Brain natriuretic peptide, also called B-type natriuretic peptide (BNP), is a hormone (protein) produced by the heart and blood vessels. BNP is released into the blood by the ventricles of the heart when they are stretched.4 It helps blood vessels to relax so that excess sodium and fluid can be excreted from the body through the urine.1 BNP levels change based on the severity of heart failure, increasing with more severe heart failure.1 The body produces higher levels of BNP to ease the strain on the heart.
Plasma ceramides is a newer test that measures ceramide levels. Ceramides are transported through the blood by lipoproteins and are associated with atherosclerosis. They are involved in the growth, function, and death of many types of cellular tissue.1
Three ceramides have been associated with a plaque in the arteries and insulin resistance. Elevated levels in the blood indicate an increased risk of heart disease within one to five years.1
Blood test monitoring
Blood tests are also used to monitor heart failure treatment. HF treatment often involves prescription medications. Blood test results can help a doctor identify the effectiveness, appropriate dosing, and side effects of the medications. Prescription drugs can impact the function of organs besides the heart. For example, people who take ACE inhibitors or ARBs (angiotensin receptor blockers) require regular blood tests to monitor kidney function.5 Other drugs can affect potassium levels or cause anemia, a low red blood cell count. Your healthcare team will use blood tests in the diagnosis, treatment, and monitoring of heart failure and its progression.5