A new study suggests that more than half of all heart attacks in women under 65 are actually not the result of a clogged artery—which is the most common cause of heart attacks in men. Having a seemingly random heart attack when you have no history of heart disease or clogged arteries is absolutely terrifying. And when the reason for that heart attack goes misdiagnosed by doctors, it could set you up for even more health problems down the road. Unfortunately, new research finds that this exact scenario happens all too often when it comes to heart attacks in women under the age of 65. The rate of heart attacks was lower in women than in men, but the researchers discovered that the cause of a woman’s heart attack was usually misdiagnosed.