It seems like a fiction novel, that an engineer can go on a personal health exploration and end up challenging everything we think we know about cholesterol and how we diagnose and monitor heart disease. 

But in reality, it may not be far from the truth.

Dave Feldman’s story is well chronicled on his website, and I am fortunate enough to call him a friend and have interviewed him many times. His upcoming documentary film Cholesterol Code will show the world the science and human emotion behind his journey and that of others. The film chronicles how ketogenic diets are changing peoples’ lives, and Dave (along with his scientific colleagues), helps us reconsider long-held beliefs about the potential risk of ketosis.

But, there are two other “co-stars” of the documentary I want to discuss – coronary calcium scores and coronary CT angiograms, both accurate, but seldom used tests for understanding heart health. As Dave and hundreds of others discover as participants in his study, LDL cholesterol may not be an accurate predictor of heart disease. As the Cholesterol Code uncovers, many people with high levels of LDL are in excellent cardiac health. So instead, we can look at our heart vessels directly and know if we have heart disease. 

As the common phrase goes, “Test, don’t guess.”

Here are the basics of what I think everyone should know about coronary calcium scores (CACs) and coronary CT angiograms (CTAs).

Calcium Score

• Relatively low radiation scan, about 1mSv (for reference a mammogram is about 0.5mSv, and yearly radiation exposure living at sea level is around 3mSv)

• Relatively low cost about $75-$200, may not be covered by insurance

• Very quick test, from check-in to leaving in as little as 10 minutes

• No intravenous contrast 

• Can usually be ordered by any physician

• Detects calcium in the heart arteries

• Does not detect non-calcified plaque or see inside the artery for blockages

• The degree of calcification correlates well with the risk of future heart events, with a zero score being very reassuring for a low 10-year risk

Coronary CTA

• Higher radiation than a CAC, but still relatively low compared to prior doses, now around 2-5mSv

• More expensive at $800-$2000 and rarely covered by insurance

• Most tests depend on a slow heart rate so may require medication and can take up to an hour or more

• Involves an iodine-based IV contrast, which is very safe but there are rare cases of allergies or kidney damage

• Often ordered by cardiologists, and less commonly by primary care doctors

• Detects calcified and noncalcified plaque, and looks inside the arteries to detect the degree of blockage and exact location of plaque

Cleerly Evaluation

• This is not a separate scan but is an additional evaluation of a CTA that has already been performed

• No additional radiation as it is an after-the-fact analysis

• Costs $850 in addition to the CTA, although some locations like Lundquist Center and many SimonMed facilities provide a bundled discount price

• Provides a cutting-edge analysis of coronary plaque with quantitative scores for total, calcified, noncalcified, and low-density plaque.

• Very helpful for quantitative follow-up over serial scans

If you are someone who identifies as a “Lean Mass Hyper-Responder” and wants to understand your heart health beyond your cholesterol levels, then I would encourage you to talk to your doctor about these tests.

Based on the above information, a calcium score is usually the best place to start for most people.  If the score is zero, there may not be a need for a CTA. But if the score is not zero and questions remain regarding cardiac risk, then a CTA may add to the clinical picture. However, these decisions should always be made in conjunction with one’s care team, as they need to be individualized for each unique situation.

You can find a doctor certified with Cleerly at the following site.