Heart disease is often called a "silent killer" for good reason – many people don’t realize plaque is building up inside their arteries until they experience a sudden, life-altering cardiac event. You might feel healthy, exercise regularly and have normal blood pressure numbers, yet you could still be at risk.
Thankfully, research at the Minneapolis Heart Institute Foundation (MHIF) is helping doctors recognize the value of looking inside your cardiovascular system. The Coronary Artery Calcium (CAC) score is a fast, safe and affordable heart scan that can help catch heart disease before it causes a heart attack. This non-invasive test allows doctors to quantify the amount of calcified plaque in your heart's vessels.
It is important to understand that a CAC score is not a cure, nor does it physically prevent a heart attack on its own. Dr. Michael Miedema, medical director at the Nolan Family Center for Cardiovascular Health at MHIF, explains it’s a powerful risk-assessment tool that can help you and your clinician decide if proactive treatment is your best next step. If you are concerned about your heart disease risk, a CAC scan can offer insight beyond standard blood work by showing what is happening inside your cardiovascular system.
What is a Coronary Artery Calcium (CAC) Score?
A Coronary Artery Calcium (CAC) score is measured with a non-contrast CT scan of your heart. Unlike more invasive medical imaging, this scan doesn't require any IVs, contrast dyes, or intense preparation. It simply takes a quick picture of your heart to measure and quantify the amount of calcified (hardened) plaque inside your artery walls.
To see why this test is so valuable, it helps to understand exactly what it does – and doesn’t – assess:
- It does quantify your calcified plaque. By measuring the buildup, it can help doctors predict your risk of experiencing a major cardiovascular event (like a heart attack) over the next 10 years.
- It doesn’t check for non-calcified plaque, which can also rupture and cause a heart attack. Nor does it diagnose an individual experiencing symptoms like chest pain or shortness of breath.
Fast, Affordable and Safe
Getting a CAC scan is convenient and easy, typically taking less than 10 minutes from start to finish. In addition, it utilizes a very low dose of radiation – about the same as a woman’s annual mammogram. Perhaps best of all, it is relatively affordable; it costs about $100 out-of-pocket at most hospitals or imaging centers, and that includes image interpretation. Although it’s not currently covered by standard insurance for screening, that policy may shift as the medical community continues to embrace the technology.
These scans are already recognized by the American College of Cardiology and the American Heart Association. Both organizations have officially incorporated CAC scans into their joint clinical guidelines as a valuable tool for clarifying a patient’s true cardiovascular risk.
This recognition comes after large clinical trials investigated provider and patients' behavior after learning of their CAC scores. Researchers found that when clinicians and patients see physical proof of plaque, it changes the approach to care. Clinicians are more likely to prescribe preventative medications and patients are motivated to adopt heart-healthy habits. Ultimately, this proactive treatment leads to a drop in cardiovascular events.
Who is a Candidate for a CAC Scan?
Given the strong clinical evidence, a CAC scan may be a prudent choice. The following recommendations can help guide this decision:
Consider a CAC scan if you are 35 or older and have one or more of the following cardiovascular risk factors:
- A family history of heart disease, especially if a parent or sibling has heart disease or suffered a heart attack or stroke.
- Elevated cholesterol or LDL cholesterol numbers.
- You smoke or have a history of using tobacco products.
- Prediabetes or diabetes (higher blood sugar levels over time increase your risk of blood vessel damage)
A preventative CAC scan is generally not recommended for the following groups:
- Very young individuals: Plaque takes decades to calcify; those in their 20s or early 30s are highly likely to score a zero.
- Symptomatic patients: This is the most critical rule of all. A calcium score is for preventative screening for people who feel fine. If you are actively experiencing chest pain, shortness of breath or unexplained fatigue, you need immediate diagnostic testing to check for active blockages.
Interpreting Results
If you have a CAC scan, taking action on your results is where the real power of the test lies. Work closely with your doctor to interpret your number and plan your next treatment steps.
A zero CAC score indicates there is no calcified plaque detected in your arteries. This scenario places you at a very low risk for a cardiac event in the coming years. That said, a zero score is not a license to ignore future heart symptoms. If you develop chest pain, shortness of breath or unexplained fatigue, you should always seek immediate medical attention.
Consider a repeat CAC scan, at least 3 years apart, only if your previous heart scan score was a zero.
A CAC score above zero indicates plaque is present in your arteries. Taking action on this early warning sign can possibly save you from future cardiac events. The higher the score, the more aggressively your risk factors need to be managed. If you have elevated plaque, the immediate goal is to lower your LDL ("bad") cholesterol. Talk with your doctor about lifestyle changes and medications to help you achieve that goal.
The Future of Heart Imaging
As valuable as the current CAC scan is, additional research is moving heart imaging into even more exciting areas. Doctors are beginning to use artificial intelligence (AI) to analyze advanced scans (called CT coronary angiography) to map your total volume and type of plaque. Even better, this AI can analyze non-calcified or soft plaque, in addition, to calcified plaque. Soft plaque is particularly important because it is often invisible on traditional scans and carries a higher risk of rupture.
Organizations like MHIF are helping drive these very advancements. The foundation continues to work at the forefront of cardiovascular research, striving toward a world without heart disease. And while medical technology is rapidly advancing, you don’t have to wait to protect your heart. There are immediate, effective steps you can take today. Start by talking to your clinician to find out if a CAC scan is the right step to put you on the path to long-term heart health.
