What are the indications for CT coronary calcium scoring, and how is it performed?
CT for coronary calcium scoring is appropriate for asymptomatic intermediate coronary artery disease (CAD) risk patients, and for the specific subset of low-risk patients in whom a family history of premature CAD is present. Intermediate risk is defined as a 10-year risk of cardiovascular events between 10% and 20% using Framingham risk factors.
Coronary calcium scoring is performed using a noncontrast, prospectively ECG-gated CT scan of the heart. It is a very safe test because no contrast material is required and radiation doses are negligible (around 1 mSv, compared to an average annual background radiation dose of 3 mSv).