You may think you know what a heart attack looks like - someone clutching their chest in pain.
But nearly half of all attacks - especially in women - don't have those symptoms.
They're called silent heart attacks.
"It started off as nausea, vomiting, sweating, chills," said Marketta Davis.
Thirty-five-year-old Marketta Davis thought she had food poisoning two days before Christmas.
She ignored it for a day-and-a-half, until she started having pain in her jaw, then her chest.
"I could put my hand there, and feel major pumping," said Davis.
A family member called 911.
Marketta finally realized she was having a heart attack when they gave her aspirin to chew in the ambulance.
"I'm too young. I thought I was going to die," said Marketta.
She did have some heart damage, and needed a double bypass operation.
Dr. Vincent Figueredo of Einstein Medical Center says women, seniors and diabetics are more likely to have heart attack symptoms that aren't typical.
"Such as the worst flu you've had in a long time, indigestion beyond what you normally feel, a muscle pull in your back that just is nagging," said Dr. Figueredo.
Women often dismiss the warning signs.
On average, they wait 54 hours to seek care, while men wait 16 hours.
"That can have devastating effects, as far as their ability to recover from a heart attack, or even survive the heart attack," said Dr. Figueredo.
Marketta is regaining her strength, with the help of her biggest supporters - her sons Semaj and Taaheed.
And she's looking forward to working again.
But she's learned a vital lesson - always listen to your body.
"If you feel any type of difference in your body, get it checked out," said Marketta. "You never know."
Signs of silent heart attack in women
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