Breast Arterial Calcification: A Novel Biomarker for Coronary Artery Disease?

There is an urgent need to identify women at risk for cardiovascular disease to prevent adverse cardiac events. Yet, a large proportion of cardiovascular events occur in women who are considered “low risk” by traditional risk stratification methods, explained a speaker at the 2022 Women’s CardioMetabolic Health and Wellness Masterclass.

In her talk entitled “Stratifying Cardiovascular Risk in Women: Biomarkers to Breast Arterial Calcification,” Dr. Lori Daniels, Professor of Medicine and Director of the Cardiovascular Intensive Care Unit at the University of California, San Diego described the need for better cardiovascular screening methods in women. Breast arterial calcification (BAC), or localized calcific sclerosis of the breast arterial media, has demonstrated promise as an emerging risk stratification tool. BAC can be detected via routine mammography, which most women over the age of 40 undergo routinely.

Studies have demonstrated that 12.7% of women undergoing mammography for breast cancer screening have at least minimal BAC. Diabetes mellitus, chronic kidney disease, and a personal history of coronary artery disease are associated risk factors with BAC. Interestingly, tobacco use is negatively correlated with the presence of BAC.[1]

Several small studies have demonstrated a positive association between BAC and coronary artery calcium (CAC) score, indicating an associated risk for subclinical coronary artery disease in women.[2,3] However, the association between BAC and angiographic obstructive coronary artery disease remains inconsistent. BAC predominantly affects the vascular media, whereas atherosclerosis predominantly affects the vascular intima.[1] This hypothesis suggests that BAC may be more closely associated to microvascular dysfunction and vascular stiffness, rather than atherosclerotic disease.

The clinical utility of BAC remains uncertain. Universal reporting of BAC on mammography would provide data for future studies assessing correlation with cardiovascular disease. Touted benefits of BAC as a risk stratification tool include no additional cost, no additional time commitment from the patient, and no need for blood draws required for other biomarkers.

“I don’t think that breast arterial calcification will ever replace CAC score, but it might help us stratify in whom we ought to be getting that and identify individuals, especially younger women, who might slip through the cracks,” stated Dr. Daniels.

Future investigation may assess the utility of automated, quantitative measures of BAC, much like CAC, rather than a binary assessment of the presence or absence of BAC. However, prospective studies will be required to identify a clear association with cardiovascular outcomes prior to widespread use of this novel biomarker.

References:

[1] Bui QM & Daniels LB. A Review of the Role of Breast Areterial Calcification for Cardiovascular Risk Stratification in Women. Circulation. 2019;139:1094–110.

[2] Yoon YE, Kim KM, Han JS, Kang SH, Chun EJ, Ahn S, Kim SM, Choi SI, Yun B, Suh JW. Prediction of subclinical coronary artery disease with breast arterial calcification and low bone mass in asymptomatic women: registry for the Women Health Cohort for Breast, Bone, and Coronary Artery Disease Study. JACC Cardiovasc Imaging. 2019 Jul;12(7 Pt 1):1202-1211.

[3] Matsumura ME, Maksimik C, Martinez MW, Weiss M, Newcomb J, Harris K, Rossi MA. Breast artery calcium noted on screening mammography is predictive of high risk coronary calcium in asymptomatic women: a case control study. Vasa. 2013; 42:429–433.