Heart imaging tests provide a picture of the heart, blood vessels, and surrounding tissue to help diagnose and monitor conditions that affect this organ.

A doctor can use the images from these tests to help diagnose heart conditions. They may also use it to monitor existing conditions and determine the effectiveness of treatments.

This article reviews the different heart imaging types, including their potential benefits, risks, and more.

Hospital monitors showing the results of a heart imaging test.Share on Pinterest
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Heart imaging tests show images of the heart, its surrounding structure, and blood flow. The images can help a doctor diagnose potential problems affecting this organ.

Imaging can refer to several different types of testing. Each test can provide additional information for the doctor to learn more about a person’s heart health and help diagnose possible conditions.

A doctor may recommend imaging tests for the heart to:

  • diagnose a heart condition
  • monitor an existing condition and check the progress of treatments
  • check the structure of the heart
  • monitor blood flow

A doctor may order additional testing and imaging to help provide a complete picture of a person’s cardiovascular health.

There are several different types of imaging tests or scans. Some of the most common include the following.


An echocardiogram, also known as an echo, uses ultrasound technology to produce an image of the heart. It is noninvasive and cannot cause pain or harm to a person.

A technician passes a transducer or probe over the patient’s chest during the procedure.

The test can help a doctor examine the structure of the person’s heart and how effectively it works. Other uses include checking for:

  • blood vessel issues
  • clots in the heart
  • issues with the outer lining of the heart
  • atypical holes in the heart
  • heart valve problems
  • cancerous growths

Cardiac CT scans

A cardiac CT scan is a noninvasive test that uses X-rays to create an image of the heart. They can show the beating heart, calcium buildup, and possible blockages in the arteries. Doctors may also sometimes add a dye into the veins to make the images clearer.

Doctors may order a CT scan when other tests do not provide enough information about the heart.

A CT can show a doctor information such as:

  • scarring from a heart attack
  • fluid in the pericardial sac that covers the outside of the heart
  • the heart’s structure
  • how well the heart pumps blood
  • calcium buildup in the arteries that can pose a risk for a heart attack
  • abnormalities in blood vessels
  • tumors affecting the heart or surrounding structures

Cardiac single-photon emission CT (SPECT)

SPECT is a nuclear imaging test that produces a 3D image of the heart. It uses radioactive tracers that healthcare professionals administer into a person’s blood system to produce an image.

Doctors can use the test to check for and diagnose CAD and determine if a person has had a heart attack in the past. It can also show how well blood is flowing through the heart. They can use the test while someone is at rest and during exercise.

Although doctors consider this a safe test, it does result in radiation exposure. The body typically processes the tracers within 24–72 hours.

However, people who are pregnant or nursing should tell their doctor before getting the test due to possible harm to the fetus or baby.

Cardiac MRI

Cardiac MRIs use a combination of a powerful magnetic field, radio waves, and computers to produce a detailed image of the heart and surrounding tissue.

Doctors may order the test to check for and monitor cardiovascular diseases. They may also use it to evaluate the heart’s anatomy after diagnosing a condition that affects this organ.

People who are pregnant or breastfeeding should speak with a doctor before taking the test.

Cardiac PET

A cardiac PET is a noninvasive imaging test that uses radioactive markers to make a picture of the heart. As a result, this test exposes people to small amounts of radiation.

Doctors may use a PET scan to diagnose coronary artery disease (CAD) and assess the damage from a heart attack. It can show a doctor which tissue in the heart is healthy and which parts are damaged. The test can also help diagnose certain diseases, such as cardiac sarcoidosis. This condition involves the growth of persistent granulomas or clumps of inflammatory cells.

A doctor can also use the PET scan to help determine if percutaneous coronary interventions (PCIs) can help an individual. PCIs refer to minimally invasive procedures for widening coronary arteries and can include coronary artery bypass surgery, angioplasty, and stenting.

Multigated acquisition (MUGA) scan

A MUGA scan uses radioactive tracers to create an image of the heart. A doctor may use it to see the dynamic properties of the heart and assess its structure.

Healthcare professionals refer to MUGA scanning as radionuclide ventriculography or radionuclide angiography.

The noninvasive scan takes several pictures at different points in time to show a picture of different cardiac cycles and produce a 2D image. A doctor may use this test when they require the precise measurement of an ejection fraction, which measures how much blood the heart pumps after a contraction. Doctors may need this measurement, for example, when monitoring the heart during chemotherapy.

Coronary angiogram or left heart catheterization

Cardiac catheterization, or “heart cath,” is an invasive test that can help determine how well the heart is working.

During the test, a doctor inserts a thin tube called a catheter into the large blood vessel leading into the heart. They will then inject a dye and use an X-ray to show how the heart is working.

A doctor can use the test and imaging to:

  • check for diseases of the valves, heart muscle, or coronary arteries
  • examine blood flow and pressure
  • check for blockages in the coronary arteries

Cardiac imaging tests do not typically need much preparation. Many are noninvasive and require that the person goes to a facility that performs the test.

A person should consult their doctor before the procedure to see if they have any specific instructions for the test.

Someone who is pregnant or nursing should let their doctor know before the test. Certain tests, such as the SPECT, may cause harm to a fetus or baby.

The outlook following a test depends on what the doctor finds. Imaging tests can help healthcare professionals examine the heart’s structure and function and the presence of diseases that may be causing harm.

A person should discuss their prognosis with their doctor.

Most people will not have any issues following a test and can leave shortly after the procedure. However, those who receive a heart cath may need to visit a recovery room for several hours following the procedure.

Heart imaging can take several forms. Different tests can tell different information about the heart, possible diseases, structural issues, and other diagnostic information.

Many types of imaging are noninvasive. However, others require dye injections and more invasive techniques. A person should discuss findings with their doctor to determine their overall prognosis, possible treatment, and plans for therapy.