Coronary Artery Calcium Score of More Than 300 Is Equivalent to Established Atherosclerotic Vascular Diseases

The estimated annual incidence of acute coronary syndrome events are 605000 for new events and 200000 for recurrent events.¹ Coronary artery calcium (CAC) score has been proposed as one of the key elements to prevent future atherosclerotic vascular disease (ASCVD). Guidelines have suggested aggressive therapy and risk factor modification at higher CAC score.^{2, 3} However, it has been unclear what cut-off of CAC score correlates with established ASCVD that would warrant aggressive intervention to prevent future events.

Researchers from multiple centers enrolled patients in CONFIRM (Coronary CT Angiography for Clinical Outcomes: An International Multinational Registry) registry in 2 phases with a follow-up of 3-5 years. Phase 1 enrolled adults without a known ASCVD and was used as a derivation cohort. Phase 2 enrolled adults with known ASCVD and similar demographics and served as the validation cohort.⁴

A total of 4949 patients were included in the final analysis, with a median follow-up of 4.7 years. The patients were divided into 4 groups based on CAC (0, 1-99, 100-299, >300) and compared with patients with established ASCVD. The mean age was 57.6 ± 12.4 years (56% male). The incidence of major adverse cardiovascular events (MACE including all-cause mortality, non-fatal MI, hospitalization for unstable angina, and late revascularization) was higher (20%) in group with CAC >300 in patients without preexisting ASCVD. The MACE rate was similar among patients with preexisting ASCVD when compared to CAC >300 (27% vs. 27%), myocardial infarction (10% vs.11%), and all-cause mortality (20% vs. 20%). Upon Cox-Regression analysis, for predictors of MACE when CAC groups compared to prior ASCVD, patients with CAC score of 0, 1-99, 100-299 were at significantly lower risk of MACE. However, CAC >300 was at a similar risk of MACE compared to prior ASCVD.⁴

This is the first study comparing CAC to that of prior ASCVD and provides crucial information regarding CAC > 300 equates to secondary prevention. The impact of this study can be practice changing for those with CAC >300 would warrant aggressive risk factor modification and treatment and can prevent future MACE.

Lead researcher and cardiologist from David Geffen School of Medicine at UCLA, Dr. Matthew Budoff, comments, “The ability to identify patients who are at extreme ASCVD risk (equivalent to an MI survivor) based upon an elevated CAC score should change our approach to these patients.  Asymptomatic persons with CAC > 300 should be treated with the same diligence as a secondary prevention patient, including greater control of lipids, blood pressure and addition of aspirin therapy.  Ongoing studies with PCSK9i and newer therapies in persons with elevated CAC are underway.”

References.

1. Tsao CW, Aday AW, Almarzooq ZI, et al. Heart Disease and Stroke Statistics—2023 Update: A Report From the American Heart Association. Circulation. 2023;147(8):e93-e621. doi:doi:10.1161/CIR.0000000000001123
2. Arnett DK, Blumenthal RS, Albert MA, et al. 2019 ACC/AHA Guideline on the Primary Prevention of Cardiovascular Disease: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. Circulation. 2019;140(11):e596-e646. doi:doi:10.1161/CIR.0000000000000678
3. Visseren FLJ, Mach F, Smulders YM, et al. 2021 ESC Guidelines on cardiovascular disease prevention in clinical practice: Developed by the Task Force for cardiovascular disease prevention in clinical practice with representatives of the European Society of Cardiology and 12 medical societies With the special contribution of the European Association of Preventive Cardiology (EAPC). European Heart Journal. 2021;42(34):3227-3337. doi:10.1093/eurheartj/ehab484
4. Budoff Matthew J, Kinninger A, Gransar H, et al. When Does a Calcium Score Equates to Secondary Prevention? JACC: Cardiovascular Imaging. 0(0)doi:10.1016/j.jcmg.2023.03.008