Results were analysed from the digital mammograms and chest CT scans of 292 women. Of the 124 who had calcium deposits in breast arteries, 70 per cent were also found, by chest CT, to have calcium deposits in heart arteries.
"Many women, especially young women, don't know the health of their coronary arteries," says the study's lead researcher, Professor Harvey Hecht. "Based on our data, if a mammogram shows breast arterial calcifications it can be a red flag - an 'aha' moment - that there is a strong possibility she also has plaque in her coronary arteries."
"This information is available on every mammogram, with no additional cost or radiation exposure, and our research suggests breast arterial calcification is as good as the standard risk-factor-based estimate for predicting risk."
"The message is, if a woman is getting a mammogram, look for breast arterial calcification. It's a freebie and provides critical information that could be life-saving for some women."
Professor Jackson, an architect of New Zealand risk-based clinical guidelines for managing cardiovascular-disease risk, says getting the breast screening programme to report on breast-artery calcium seen in digital mammograms, as a new heart-screening tool, is worth investigating in this country.
"Women do get mammograms anyway so it's not like you are giving them any additional radiation."
"If they save the old mammograms, someone could look back and read them again and then link through the NHI [national health index number assigned to each patient] to [cardiovascular] events. We could study it here."
Women can have state-funded mammograms between the ages of 45 and 69. The recommended age for women without any risk factors or symptoms to start having cardiovascular risk assessments is 55 for NZ Europeans and 45 for Maori, Pacific, Indian and Asian women and those with any risk factors, including smoking and high blood pressure.
A CT scan at a private radiology clinic to check the heart arteries for calcium deposits - called coronary artery calcium scoring - costs around $300.
Calcium tests
• Women's mammogram scans for breast cancer can also show calcium deposits in their breast arteries
• Having calcium deposits in breast arteries is linked to also having them in heart arteries
• Heart-artery calcium deposits are an early sign of cardiovascular disease
• Researchers say mammograms could be used for heart checks