Coronary artery disease (CAD), also called atherosclerosis, is the most common type of heart disease in the U.S. CAD happens when fatty deposits called plaque build up in the arteries, which are the blood vessels that bring blood back to the heart. Many people with the condition don’t know they have it until they have a heart attack. A heart scan, a type of cardiac imaging, can often help diagnose CAD and other heart issues before they cause a serious issue. Cardiac imaging can also monitor your heart health and help prevent future problems if you have already been diagnosed with CAD.
Cardiac Imaging for Heart Health
A variety of imaging tests are available to detect, prevent, or monitor heart conditions. These tests can show blood flow in and around the heart, the functionality of the heart muscle, and the structure of blood vessels and the heart.
Two commonly used imaging tests used to assess heart health are a coronary computed tomography angiography (CCTA) and a calcium scoring test, also called a coronary artery calcium (CAC) test or coronary calcium scan. Both of these imaging tests involve a CT scan.
A CT scan is a noninvasive Imaging test that uses advanced X-ray technology to create cross-sectional pictures of the inside of the body. You can view these pictures as single images or combine them to create a 3D computer model of the heart and surrounding area. Compared to traditional X-rays, CT scans show clearer images and more details of blood vessels and soft tissues.
What a CCTA Heart Scan Shows
During a CCTA scan, the radiology technologist uses the CT scanner to take images of the blood vessels around the heart or other parts of the body. These images can reveal:
- Fluid accumulation around the heart
- Narrowing of the coronary arteries
- Plaque buildup in the coronary arteries
- Scarring in the heart muscle due to a previous heart attack
- Structural issues with the blood vessels or heart
This information helps your provider determine the cause of your symptoms, your risk for a heart attack, and the most appropriate treatments for you.
Calcium Scoring Tests and Coronary Artery Disease
A calcium scoring test can detect calcium buildup in the coronary arteries. These calcium deposits are a sign of CAD.
For a calcium scoring test, your radiologist will examine the CT images to determine if you have any calcium deposits and where they’re located. Test results are rated on a scale of zero to over 400. This number is called a calcium score or Agatston score. If your calcium score is zero, you do not have any calcium deposits. Higher calcium scores mean that deposits are present and provide information about the severity of coronary artery disease.
A score of one to 10 indicates minimal CAD. A person with a calcium score of 11 to 100 has mild CAD. Those with moderate CAD have a score of 101 to 400. People with a score over 400 have extensive evidence of CAD. The higher the calcium score, the more likely it is that a person will have a heart attack in the next five years.
Knowing your calcium score can help you and your provider make decisions about treatment options for CAD, such as whether to take low-dose aspirin or start statin therapy.
What to Expect During Your CT Scan
During a CCTA or calcium scoring test, a radiology technologist will take images while you lay on the CT scanner table. They will ask you to hold your breath for 10 to 20 seconds at a time as they take the pictures. This helps ensure the images are clear and not blurry.
Generally, a CT test takes about 10 to 15 minutes. However, your appointment may be longer to help you prepare for the scan. CT scans involve a small amount of radiation exposure. Still, for most people, the benefits outweigh the risks.
In addition to taking pictures of your heart and nearby blood vessels, images from a CT scan also show the surrounding bone and soft tissue. This helps your radiologist detect other possible concerns, such as a blood clot in the lung or an issue with the aorta, a large blood vessel that brings oxygen-rich blood from your heart to the rest of your body.
For a CCTA scan, contrast dye is injected through an IV before your CT scan. This dye makes certain types of tissue stand out from others in the images, creating a clearer picture.
Who Benefits From a CCTA or Calcium Scoring Test
Your doctor may order a CCTA if you have acute, chronic, or worsening chest discomfort or pain, especially if other heart tests have not shown the cause of your symptoms. CCTA scans can also help diagnose heart issues in people who are unable to have more invasive heart testing.
Doctors generally recommend calcium scoring tests for individuals who have an intermediate risk of heart disease due to risk factors but do not experience heart-related symptoms such as:
- A sedentary lifestyle
- Being overweight or having obesity
- Diabetes
- High blood pressure, also called hypertension
- High cholesterol
- Family history of heart attacks
- Smoking
Calcium scoring is typically not needed for people with a low risk of heart attack and heart disease and no heart-related symptoms or for those at high risk for heart disease.
When to Talk With Your Provider About a Heart Scan
If you have risk factors for CAD or a heart attack, have a history of heart issues, or have heart-related symptoms, it’s time to talk with your provider. They can assess your health and determine if a heart scan is right for you.
