Have you ever wondered about the health of your heart arteries? Like most people, you may have heard of or personally know someone who suddenly had a heart attack out of the blue. Perhaps it was a close family member like a parent, sibling, spouse or adult child. The physical and emotional toll that it can take on the affected person as well on their family members can be very traumatic and often leads one to question how the heart became so vulnerable in the first place. This is especially the case if the affected person was younger and had no symptoms leading up to the tragic event. The statistics are sobering. Heart disease remains the #1 leading cause of death in the United States and in nearly all developed countries worldwide. Even more sobering is that only 50% of people have the usual warning signs of a heart problem before having a heart attack. The remaining 50% have no classic symptoms that many equate to a heart problem such as chest pain.
Let’s look at Arthur’s story. Arthur just turned 55 years old and like many Americans, he has high blood pressure treated with medications as well as mildly elevated cholesterol. However, what concerns Arthur is his family history. His dad had a heart attack when he was in his early 60s which led Arthur to ask his doctor what his own risk of suffering from a heart attack would be. His doctor, like most physicians in America, used a risk calculator created by the American College of Cardiology, to assess Arthur’s 10-year heart attack risk (link). His projected event risk came back at 7.1% which is just below the 7.5% risk threshold that would indicate a strong recommendation to start cholesterol-lowering or statin therapy. However, his doctor still recommended that he start cholesterol or statin therapy given his family history, but Arthur is on the fence about it. His thinking is that he feels well, goes out for a walk most days of the week, rarely eats fast food, and in fact, eats an apple a day! According to Arthur, he lives a much healthier lifestyle compared to his dad when he was his age.
Upon hearing his hesitation to start cholesterol-lowering therapy, Arthur’s doctor recommended a heart artery calcium scan to investigate further.
Also known as a calcium score, it’s a test that has been available since the early 1990s and is one of the most powerful heart disease risk predicting tools in a cardiologist’s toolbox.
What does a coronary calcium scan do?
The scan provides images of a person’s coronary arteries that show existing calcium deposits. Called coronary calcifications, these deposits are an early sign of coronary artery disease.
Pictures of the heart are taken while a person lies in a CT scanner for about 10 minutes. The amount of radiation that is received with the scan using today’s modern CT scanners is 1 millisievert and under. This is slightly more than is received with a typical mammogram. Also, it’s important to note that no intravenous contrast is given during the study.
What are the scores?
A perfect coronary artery calcium (CAC) score is zero. A low-risk scan is typically 1-100. A medium-risk scan is 101-400 and a high-risk scan is over 400. CAC scores are usually given with an age-adjusted percentage ranking which tells a person how they rank against other men and women their age.
Calcium Score in Predicting Cardiac Events
Looking at grouped data from a collection of studies that have monitored people over the years after having received a calcium score, the rates of a person having a heart attack, heart-related death, stent or heart artery bypass procedure were very discerning in being able to predict who is truly “low risk” and “high risk.”
Who should get a calcium scan?
For individuals who feel well (i.e. no concerning heart-related symptoms), over the age of 40, who have several risk factors for heart disease, the test can help determine how aggressive treatment should be, whether different types of medications should be started. On the upside, it can also determine whether a person is at very low risk for heart events. Unlike the risk calculators that many doctors use to predict heart attack risk, the calcium score provides actual and actionable information about a person’s heart arteries.
Who should NOT get a coronary calcium scan?
The calcium heart CT scan is not for everyone. It is not typically used in those who are of very low heart disease risk which is usually people under the age of 40. It is also not an ideal test for those over the age of 75 or in those who already have known heart disease which includes those with heart artery stents or previous bypass surgery. Ultimately, the best way to determine whether it is a good test for you is to ask your primary care doctor or cardiologist.
Let’s get back to Arthur
Arthur’s Score came back at 450. This is considered a high-risk scan and places Arthur at a higher risk of heart attack, heart related death and/or needing a stent or bypass surgery in both the short-term and long-term compared to other men and women his age. Unlike the risk calculator that projected a 7.1% 10-year heart event risk, the calcium heart scan projected a much higher 22.5-22.8% 10-year heart event risk. Furthermore, it revealed that compared to his peers, Arthur’s score was in the 95th percentile. This means only 5% of the U.S. population his age and ethnicity are estimated to have a higher score.
Having heard this Arthur was now motivated to take the cholesterol medications prescribed by his doctor as well as drastically alter his eating and exercise habits.
So, let’s summarize. The Calcium Heart scan is used mostly in individuals over 40 years of age who have no cardiac symptoms but have risk factors for heart disease present. It provides short-term and longer-term risk prediction of adverse heart events like heart attack and need for a stent or bypass surgery. It is commonly used for people who are on the fence, so to speak, about starting cholesterol lowering medications. It also serves as a motivating factor for people to eat a heart healthy diet or exercise more. For the many fortunate people who have a score of zero, it serves a badge of health!
The Coronary Calcium CT is not covered by most insurance companies and typically costs a person about $100-150. It is important to note that a score of zero is NOT a guarantee that a person will not suffer with a heart event but simply that the probability is exceptionally low. The benefits of this test, in the right people, are many. Talk to your doctor about whether this test is right for you.
If you found this article useful, check out the corresponding video here (link).
