The classic image of a heart attack victim is a man clutching his chest. Of course, women can be affected, too. In fact, more women than men die of heart disease each year in the US.

Now: New research shows that women who suffer heart attacks may be undermining their own survival, in part, because they are reluctant to call an ambulance for themselves. By underestimating the seriousness of their own symptoms—and prioritizing other people’s needs—women could be depriving themselves of possibly lifesaving treatment.

Study details: In research presented at an Acute Cardiovascular Care conference of the European Society of Cardiology in Malaga, Spain, researchers tracked 7,582 men and women who suffered a heart attack caused by a major artery blockage. When treating this type of heart attack, known as an ST-elevation myocardial infarction (STEMI), the goal is to resolve the blockage as promptly as possible—restored blood flow means less heart tissue death…a lower risk for future heart failure…and a lower overall risk for death.

It’s recommended that treatment (opening the blocked artery with a stent) begin within 90 minutes of diagnosis. The quickest way to diagnose a heart attack is via an electrocardiogram (ECG) that is administered in an ambulance as the patient is being transported to a hospital. In this study, 45% of patients were treated within that crucial 90-minute window, but fewer of them were women (41% compared with 47% of men).

The research also showed a disparity in the use of ECG during the ambulance transport. While 40% of men of all ages received an ECG, on average, only 34% of women age 54 and under got tested in the ambulance (45% of women age 75 and older were tested).

The treatment delay in women was due, in part, to women hesitating to call an ambulance for themselves, according to the researchers. Women put off making that call because they believed they minimized the seriousness of their symptoms and/or had too many responsibilities, including their work and child-care duties. The researchers noted that this is especially true of younger women (under age 55).

Women may also fail to recognize their own symptoms as those of a heart attack. Chest pain and tingling in the left arm are the classic symptoms, but they may have pain elsewhere, such as the back, shoulder or stomach.

“In addition to running the household, women make sure that male relatives receive urgent medical help when needed,” said research coordinator Marek Gierlotka, MD, PhD, associate professor of cardiology at the University of Opole, Poland. “It is time for women to take care of themselves, too.” Even though the study was conducted in Poland, the researchers believe that the findings are likely to apply to women living in other countries.

Takeaway: Don’t wait! Call 911 if you or anyone around you experiences possible heart attack symptoms, such as pain in the chest, but also in the jaw, throat, neck, shoulders, back or stomach for 15 minutes or longer. Fast treatment benefits both sexes equally.