Higher CT CAC scores indicate future heart problems

Coronary artery calcium (CAC) levels spotted on CT scans in middle-age patients were connected to an increased risk of structural heart abnormalities indicative of future heart failure, according to a new study published in Circulation: Cardiovascular Imaging.

After tracking more than 2,000 people from young adulthood to middle-age, those with higher CAC scores on CT imaging at middle-age were more likely to have structural abnormalities in the left ventricle—a risk factor for heart failure—compared to patients who had CAC scores of zero.

These findings were especially pronounced among black patients, according to co-author Henrique Turin Moreira, MD, PhD, with Hospital das Clínicas de Ribeirão Preto at the University of São Paulo in Brazil, and colleagues.

"Given the burden of morbidity and mortality associated with heart failure, these are important findings,” Moreira said in a news release. “Prior studies from this cohort have also shown that a better risk factors profile in young adulthood is associated with much lower CAC and therefore, these results further highlight the importance of primordial prevention and risk factor modification in early adulthood."

As part of the CARDIA (Coronary Artery Risk Development in Young Adults) study, the researchers tracked 2,449 people (52% white, 57% women), comparing their CAC scores on CT imaging at 15 and 25 years.

CAC is a buildup of calcified plaque, which, when compounded over time, can lead to atherosclerosis—a narrowing of the channel in an artery, limiting blood flow.

Overall, at year 25, the average patient age was 50 and 72% had a CAC score of zero compared to 77% with a zero score a decade prior. Additionally, CAC scores were independently related to increasing age, male sex, black race, higher systolic blood pressure, elevated total cholesterol, diabetes mellitus, current smoking and the use of medications to lower blood pressure and cholesterol.

Middle-aged participants with higher CAC scores also had a 12% increase in left ventricular mass and a 9% increase in left ventricular volume, independent of other risk factors.

Those findings were especially pronounced among black patients. For each one-unit change in a CAC score, blacks had a four-times higher increase in left ventricular mass compared to their white counterparts. Progression in CAC during the follow-up period was also strongly related to higher left ventricular mass for this group, but not significant in whites.

“Racial differences in our findings may be due to genetic factors or perhaps greater exposure to cardiovascular risk factors that usually appear earlier in blacks," Moreira said in the same release. "We need more research to examine the link between coronary artery calcium and heart health."