Tests used to diagnose heart failure
You will have tests to see how bad your heart failure is and what caused it. Common tests include:
- Blood tests help us understand how well your kidneys and thyroid are working. We will check your cholesterol and red blood cell levels for high cholesterol and anemia. Anemia means the hemoglobin (HE-mo-globe-in) level in your blood is lower than normal. Hemoglobin is the part of your red blood cells that makes it possible for blood to carry oxygen through the body. Low hemoglobin levels cause you to be tired and have other symptoms that are similar to those of heart failure.
- NT-pro**B-type Natriuretic Peptide (BNP) blood test**. BNP is a hormone that is released into the blood by the lower chambers of the heart (ventricles) in people with heart failure. NT-pro BNP is an inactive molecule that is released in the blood with BNP. The level changes based on how severe your heart failure is. Higher levels of NT-pro BNP mean the ventricles are more stressed. Low levels mean your heart failure is stable. If you have shortness of breath, the level of NT-pro BNP in your blood can help your doctor know if it is caused by heart failure. A level of more than 450 pg/mL for patients under age 50 or 900 pg/mL for patients 50 and older could mean you have heart failure.
- Cardiac Catheterization. If you are scheduled for a catheterization, your doctor may check your EF during the procedure. A catheterization lets your doctor check your heart from the inside. A long, thin tube called a catheter is inserted into an artery in your arm or leg. The doctor uses a special X-ray machine to guide the catheter to your heart. There are two types of cardiac catheterization — left and right. If you have a left heart catheterization, your doctor may inject dye to record videos of your heart valves, coronary arteries and heart chambers (atria and ventricles). A right heart catheterization does not use dye; it lets your doctor know how well your heart is pumping blood.
- Chest x-ray shows the size of your heart and any fluid build-up around your heart and lungs.
- Echocardiogram (echo). This is an ultrasound to see how well your heart can pump and relax, to check your heart valves, measure your heart and check blood flow. Images are captured using an ultrasound wand that is moved around on the skin of your chest. An echo is often done with a Doppler test so your doctor can see changes in the pressure inside your heart chambers and in the way your blood flows across your heart valves. This is the most common way to determine your EF.
- Ejection fraction (EF). Your EF is a measurement of the blood pumped out of your heart with each beat. Your EF can be measured using an echocardiogram (echo), multigated acquisition (MUGA) scan, nuclear stress test, magnetic resonance imaging (MRI) or during a cardiac catheterization. Ejection fraction is reported as a percentage. A normal EF is between 55% and 70%. Your EF can get better or worse based on how stable your heart failure is and how well your treatment for heart failure is working. It is important for your doctor to know your EF. You should have your EF measured when you are diagnosed with heart failure and as often as your doctor recommends.
- Electrocardiogram (EKG or ECG). This test records the electrical activity in your heart by using electrodes that are connected with wires to an electrocardiograph monitor. Electrodes are small sticky patches that are placed on your body. The wires carry information to the monitor, and it creates a graph to show the electrical activity.
- Multigated Acquisition Scan (MUGA scan) . This test shows your doctor how well the lower chambers of your heart (ventricles) are pumping blood. A small amount of a radioactive dye is injected into a vein. A special camera (gamma camera) is used to create video of your heart as it beats.
- Stress test. This test shows how your heart reacts to stress. You will likely exercise on a treadmill or stationary bike at different levels of difficulty while your heart rate, electrocardiograph and blood pressure are recorded. If you cannot exercise, medication may be used to create the same effect as exercise on your heart (pharmacological stress test).
Other tests may be needed, depending on your condition.