Starting October 1, 2026, a new Maryland law requires mammogram reports to explicitly tell patients this: if the imaging shows breast arterial calcifications (BACs), it may indicate underlying heart disease. It is the first state law of its kind in the United States.
Until now, mammography reports talked only about cancer. BACs are calcium deposits in the walls of breast arteries, appearing on scans as thin, bright "tram track" lines — entirely different from the calcifications radiologists look for when screening for breast cancer. Radiologists have actually been seeing them for decades. "They take a few seconds to spot," says Dr. Tahira Ahmed, medical director of Breast Imaging at the Maryland Imaging Network–RadNet. Nobody just acted on them.
The research is solid. A 2022 clinical study found BACs associated with heart disease in postmenopausal women ages 60 to 79; a 2024 study went further, finding BACs "especially predictive" in younger women ages 40 to 59. A study published in March in the European Heart Journal used AI to analyze more than 120,000 mammograms: women with the highest levels of calcification had double the risk of major cardiac events — heart attack, stroke, heart failure, and death — compared with women whose scans showed none.
A June study of more than 4,300 women with no prior heart disease found a BAC prevalence of 8.04%. Extrapolated to the roughly 43 million mammograms performed in the U.S. each year, about 3.4 million women could be flagged for cardiovascular assessment. Prevalence ran notably higher in Black and Hispanic women — a health disparity worth confronting.
Northwell Health in New York began voluntarily reporting BACs in early 2024, analyzing 88,000 mammograms between January and October of that year. "BACs can be a woman's first sign of heart disease," says Dr. Nisha Parikh, director of cardiovascular disease at Northwell's Katz Institute of Women's Health.
Maryland turned "voluntary" into "mandatory." The logic: women are already getting screened — more than 40 million mammograms a year in the U.S. — so adding one line of warning where they already are costs almost nothing, and could surface silent cardiac risk years early.
A Tel Aviv University team showed at the European Society of Cardiology meeting that an AI model trained on 97,364 mammograms from 29,921 women could identify women with a history of stroke 86% of the time, and distinguish those with hypertension and coronary heart disease at about 79% and 78% accuracy. The vision: AI revisiting mammograms already sitting in a patient's record to ask questions the images were never originally meant to answer — no extra scan required.
Doctors stress one point repeatedly: having BACs does not mean having heart disease, and it is not a reason to start medication. It is a risk signal — a prompt to talk with your primary care doctor about cardiovascular screening. Heart disease is the leading cause of death among U.S. women; CDC data show more than 60 million American women live with some form of it, and it is "still too often recognized late" in women. "It is a clarion call that younger women do have risk, that it can be detected, and that detection of risk should lead to interventions," says Dr. Mary Cushman of the University of Vermont.
Maryland's mandatory notification is now in effect. Whether other states follow is the thing to watch. Reporting BACs has almost no technical barrier — a radiologist spots them in seconds. The hard part was deciding whether to say anything. Now the law has made that decision for them: say it.