Dear Dr. Roach: I am now 78 years old. My mother’s two brothers died of heart attacks at 55 and 65, so when I was in my 50s, I had a calcium scan of my heart. Since then, I have been taking 10 mg of atorvastatin along with blood pressure medication.

Last year, I had my aortic valve replaced, and an angiogram showed about 30% blockage in my coronary arteries. This makes me believe a statin drug is a good preventative for artery blockages. Do you think that anyone with a family history of heart disease should get a calcium scan? — R.S.

Answer: A calcium scan is a special kind of X-ray that identifies calcium-containing plaque in heart arteries. It is not a direct look for blockages.

It’s possible to have a normal calcium score and still have blockages. Most blockages in the arteries are a combination of cholesterol plaque and calcium, but not all have calcium. Further, some people have calcifications with no blockages.

Doctors use specialized calculators that can help predict 10-year risk of a coronary event. If a person has high-enough risk to be on treatment anyway, a calcium score isn’t necessary to recommend treatment. A person with very low risk is unlikely to have coronary calcium, and even if they do, it might not mean blockages. For those who fall into the middle, the coronary calcium score provides additional useful information that can help a doctor decide whether medication therapy is appropriate.

The joint guideline from the American Heart Association and American College of Cardiology recommends against the use of coronary calcium screening for people of otherwise low risk with a family history. The calculators do not take family history into account (there are other risk factors as well that are not in the calculators), so a doctor must exercise individual judgment. I have certainly ordered diagnostic testing in people who have low calculated risks but who have other risks not in the calculators (such as a patient of mine with a twin brother who needed a bypass).

A wise doctor doesn’t make decisions based on only one risk, whether it’s cholesterol or family history. The whole person — all their risk factors and protective factors, their ability to improve lifestyle, and their tolerance for medication — must be taken into account before making a truly personalized recommendation.