Diagnosis Heart Failure: Imaging Tests
To diagnose and monitor heart failure (HF) providers use many different diagnostic tools. A physical exam and blood work are generally the first two steps. Cardiovascular imaging can provide information about the underlying cause of heart failure.
Imaging technology continues to advance and offer providers more information about structural and functional changes in the heart. The tests range in time, risk, and cost.
A chest X-ray uses a small beam of radiation to create an image on a specialized film.1 It produces an image of the heart, lungs, and bones of the chest. It can pinpoint the location, size, and shape of the heart, lungs, and blood vessels. Chest X-rays can show if there is congestion in the lungs or if the heart is enlarged.2
An EKG measures the electrical activity of the heart. With every beat the heart muscle contracts, pumping blood throughout the body.3
Small electrodes are placed on the chest with wires that run from the electrodes to the EKG machine. The machine records the heart's rhythm, frequency of beats, and electrical conduction. EKGs show how long it takes for the electrical wave to travel from one part of the heart to the next.3 The results, sometimes referred to as a strip, display any irregularities in the rhythm, as well as changes that indicate a past heart attack, or if the heart is enlarged and the left ventricle is thickened.4
An echocardiogram, called an echo for short, is a test that uses high-frequency sound waves known as ultrasound to create moving images of the heart.5 With more detail than an x-ray, it allows doctors to see the heart’s structure and motion, creating images of the chambers and valves. The echocardiogram shows the thickness of the heart muscle and pumping ability. This test can measure the heart’s ejection fraction.2
The information in an echo can help doctors identify the type of heart failure either systolic or diastolic. It may also tell you if the cause is valvular or from high blood pressure.6
A cardiac CT scan is a noninvasive test that collects images of the heart and chest.7 The test is performed inside a doughnut-shaped machine that uses an X-ray tube.4 It can be performed with or without contrast iodine dye which is often used to enhance the images of blood flow through the vessels of the heart.
The images show the beating heart, any calcium deposits, or arterial blockages.7 It allows the provider to see the structure and pumping ability of the heart, any fluid accumulation, scar tissue, or narrowing of the arteries.7 It is often used to help the healthcare team assess an individual’s risk of heart failure.
Magnetic Resonance Imaging (MRI)
MRI is a noninvasive test using a magnetic field and radio waves to create images of the heart, blood flow, and blood vessels.4 MRIs can show tissue damage, reduced blood flow, aneurysms, blockages, and issues with heart valves.8
Positron Emission Tomography (PET)
A PET scan is a noninvasive nuclear imaging test which radioactive tracers, radionuclides, to create images of the heart. Tracers are injected into the blood and enter the heart muscle. A detector recognizes the tracers and a computer converts the signals into images of the pumping heart.9
The scan creates a 3-D image of the heart using thin-sliced images. These images show if the heart has sufficient blood flow or if it is reduced due to a narrowing of the arteries.9 It is an effective way to diagnose coronary artery disease.2
An angiogram is a surgical procedure where a flexible catheter is inserted through the groin or wrist into an arterial blood vessel and guided up through the aorta into the coronary arteries. A dye is injected into the catheter making the arteries visible, allowing doctors to see any blockages.4
There are other tests available to cardiologists to diagnose and monitor heart failure. For questions about these tests or others, talk to your health care team.