Close your eyes and picture someone having a heart attack. What kind of person did you visualize? Most likely, your mental image was of a man.

The truth is that heart disease doesn’t discriminate: It’s the number-one killer of women globally, accounting for as many as one in three female deaths. Heart attacks are also twice as likely to be fatal in women, in part because women more often experience a multitude of symptoms—fatigue, nausea, back pain—in addition to the classic chest pain. “A heart attack might get lost in the noise,” says Dr. Stacy Trent, an emergency department physician and associate professor at the University of Colorado Anschutz Medical Campus.

In theory, a simple blood draw should cut through the din. But the test ERs have long used to appraise a patient’s level of troponin—a protein released into the bloodstream during a heart attack—wasn’t sensitive enough to catch many female heart attacks. “New research was able to show that the abnormal level of troponin for women is much lower,” Trent says. Tests developed over the past decade are 10 to 100 times more sensitive, but doctors are still figuring out how to interpret the results.

That’s why Trent is leading a study to see if patients in Denver who use the advanced evaluations have better outcomes. It’s too soon to say, but she’s hopeful: A 2019 study found that with the new tests, women were roughly three percent more likely to be diagnosed with a heart attack. That increase may sound small, but to the people whose lives were saved, it’s enormous.

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