Viet Le, PA-C: Value of Disproportionate CAC vs Total CAC for Predicting MACE

The utility of coronary artery calcium (CAC) scoring for identifying individuals at risk of major adverse cardiovascular events has emerged as one of the great prognostic advances in atherosclerotic cardiovascular disease in the last half-decade.

As the field continues to move into the future, further research has begun to better define the prognostic role of CAC scoring in real-world care, including new data at American College of Cardiology’s (ACC) 2023 Annual Scientific Session Together With the World Congress of Cardiology from an Intermountain Medical Center Heart Institute-led team examining the value of overall CAC score comparative to per vessel CAC distribution.

Using electronic medical record data, investigators identified a cohort rom 7527 patients with a CAC score greater than 0, as measured with a PET/CT or stand-alone CT, for inclusion in their analyses. Investigators classified patients as having disproportional CAC if at least 1 vessel had a 50% or greater than the average percentage, which was defined as greater than 76.5% of CAC in the left anterior descending artery, greater than 37.5% in the right coronary artery, greater than 25.5% in the left circumflex artery, or greater than 10.5% in the left main coronary artery. Investigators classified patients as double if right coronary artery, left circumflex artery, or left main coronary artery had CAC greater than 100% compared to the average or the left anterior descending artery had CAC greater than 90% compared to average.

For the purpose of analysis, these groups were compared against a reference group of patients without disproportion CAC in any vessel, which was defined as less than 50% increase compared to the average percentage.

Initial analysis revealed 89% of those included in the study had disproportion CAC in at least 1 vessel and 69% had double the average of CAC in at least 1 vessel. Compared to their counterparts without disproportional CAC, those with disproportional or double CAC were more likely to be younger and female but less likely to have diabetes, hypertension, and hyperlipidemia.

Further analysis indicated those with disproportional or Double CAC in at least 1 vessel had a lower ischemic burden and no increase in MACE rates compared to those without. Investigators highlighted increases in total CAC scores were associated with increased MACE (P <.001).

For more on the results of the study and its clinical implications, we sat down with study presented Viet Le, PA-C, associate professor of research at Intermountain Healthcare, while on site at ACC 2023.

Reference:

1. Le V, Anderson J, Bride D, et al. DISPROPORTIONAL AMOUNT OF CORONARY ARTERY CALCIUM (CAC) IN A VESSEL DOES NOT INCREASE LIKELIHOOD OF MAJOR CARDIOVASCULAR EVENTS (MACE). J Am Coll Cardiol. 2023 Mar, 81 (8_Supplement) 1304. https://doi.org/10.1016/S0735-1097(23)01748-5

Viet Le, PA-C, has no disclosures to report.