Value of Coronary Calcium Score
Heart disease remains the number one cause of death in the United States, causing 1 million heart attacks a year. Up to 1/3rd of all heart attacks occur in people without any symptoms until the day of the actual attack. What’s profound is that half of these people may have normal or even excellent cholesterol profiles and normal stress tests. So what else can be done to better predict if you’re at risk of a heart attack?
The answer : A coronary calcium scan.
A Coronary Calcium Scan is a simple quick no-contrast CAT scan of the heart that specifically measures how much calcium is built up in your coronary arteries, the arteries that supply blood to your heart. The more the calcium built up, the higher your Calcium Score which means a higher risk of heart disease. That calcium buildup is a marker for heart disease and calcification often implies narrowing of the arteries. A study of 44,000 individuals without known heart disease who had calcium score >400, even if they did not have risk factors like diabetes, high blood pressure, or high cholesterol still had substantially higher death rates compared to people with no coronary calcium. That means “normal healthy” people with normal blood pressure and normal cholesterol BUT high coronary calcium scores are more likely to die.
So what’s a high score? Generally any score >50 is worrisome but a score >400 means you have a buildup of plaque and you’re risk a heart attack in next 5 years is high.
Now a high calcium score does not directly mean your arteries are blocked with plaque or calcium. It’s a predictor, much like cholesterol. It’s a very good predictor. And unlike often used measures like your cholesterol and Framingham Risk Score, this is a 5 year risk predictor. Which is another reason why I like it. If I know I have a 30% chance of heart attack in next 5 years, I’m more likely to take aggressive measures to reverse heart disease than if you told me it’s 10 years away.
There are a couple short comings to point out. First a score of zero does not guarantee you won’t have a heart attack in next 5 years. While the test does a great job telling us if you have hard calcified plaque, it misses soft plaques. Second, since it’s a CAT scan, there is a low amount of radiation. However, the radiation is no more than 1 to 2 mammograms and unlike a mammogram, you typically you only need this scan done once. Third, it can pick up incidental findings such as a tiny lung nodule that warrants further testing. Finally, since it’s a screening test, it’s not covered by most insurance or Medicare. However our local hospital, St Mary does them for $125 which is a bargain.
Bottom line, I believe this test is probably one of the most useful screening test for heart disease, along side C-reactive protein, cholesterol, and stress test performance. In 2013 I met President Clinton at a preventive cardiology conference and he relayed his story of chest pains and his heart attack and need for bypass in 2004. Ironically, he had a calcium score while he was President. He regrets his White House doctor’s did not pay attention to it since it predicted he would have a heart attack. By the time he had symptoms, his heart diseases was decades into the making. George W. Bush’s doctors would not make the same mistake. In 2006, he also had a calcium scan which detected early heart disease in him, despite being an avid mountain biker and cyclist. In fact calcium scores are done across the country at leading centers such as Mayo Clinic, Cleveland Clinic, Hopkins, Cooper Clinic, etc. For people who are concerned about heart disease, I strongly recommend this test. And if it’s positive, let’s talk.
A special thank you to my patient Gerry who requested I comment on this test.