It's a concern for healthy people, but especially if you have a chronic condition or are taking any heart medications. Doctors offer some reminders that you should take to heart.
"I love hot weather," said Renee Williams as she toured the Hollywood Walk of Fame.
While some people thrive in the heat, we sometimes forget the toll it takes on our bodies.
"It can make me pretty grumpy especially when that dehydration kicks in," said Neveah, another tourist from Chicago.
"People who are exposed to the heat or humidity, they tend to get dehydrated," said Dr. Carlos Gonzalez Lengua of Cleveland Clinic.
Hot weather means your body has to work harder pumping blood to keep your core temperature close to normal. This puts extra strain on many organs including your heart.
"It means their heart beats faster than usual, and at times, that increases inflammation," said Gonzalez.
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Doctors say inflammation is a result of your body compensating for the heat. It can possibly cause blood clots, which can lead to a heart attack or stroke.
And while extreme heat can impact everyone's heart, older people and those with preexisting heart issues are especially at risk.
It's also important to remember that certain blood pressure drugs as well as other medications can increase your risk of dehydration so don't over do it outdoors in the sun.
"You got to take breaks, drink some water and get some shade when you can," said Brett Cione of New York.
To avoid issues during a heatwave, Gonzalez said if you can, try to stay inside at the hottest points of the day.
"There's a lot of air conditioning nearby so I'm relying on that," said Nevaeh.
Gonzales said think about going to places where you can stay cool.
"If you really want to get out of your house, maybe go to the mall, grocery stores, to the local pool. And, you know, keep yourself hydrating well," he said.
If you start feeling fatigued on a hot day, Gonzalez said it's crucial to promptly find a way to cool down and drink plenty of water.
Don't hesitate to call 911 if you start experiencing symptoms such as chest pain.