The snow piling up outside your door may be screaming to be shoveled, or perhaps played in, but be careful before you bundle up and step outside, cardiologist Michael Zabel says.

Zabel, a doctor at Cardiovascular Specialists of Lawrence, said weather like today’s can pose a number of risks: heart episodes, dehydration, falls or even hypothermia.

Everyone should exercise some caution, he said, but first of all: If you have any history of heart issues, stay inside. And whatever you do, do not try to shovel off your driveway.

“For anybody that has a cardiac history, shoveling snow is just about the worst thing to do,” Zabel said.

Shoveling snow is an isometric activity — lots of pushing, straining and pulling — which is the opposite of the more cardiovascular exercise doctors encourage for patients with heart problems, he said. And the cold weather only increases the risk.

So if you’ve had a heart attack, angioplasty, abnormal rhythms or any other such problems in the past, plunk down $10 for the shoveling services of a child in your neighborhood.

Sadly, Zabel said, every time there’s a big snowfall, he and other cardiologists tend to hear from at least one person with heart problems who did more than he or she should have.

“We’re going to have it today,” Zabel said at about noon Thursday. “I’m sure we will.”

If you don’t have heart issues, feel free to go outside and shovel, he said. But be careful.

Be sure to take a break every 15 minutes, or more often if the cold or wind is severe. That means you should go inside, take off your winter clothes, let any sweat dry off and drink plenty of fluids. You can get pretty sweaty working outside while all bundled up, which strips your body of water and can make you colder.

“It’s easy to get dehydrated and not know it,” Zabel said. “We don’t feel as thirsty when the weather is cold as when the weather is hot.”

Venturing outside when there’s snow or ice on the ground can also be risky for the elderly, he said, though age isn’t everything, of course. Some 70-year-olds will be fine walking on slick terrain, and some 40-year-olds should stay inside.

Whatever your age, if you’re unsteady or at risk for falling for any reason, it’s best to stay inside, he said. Many people who break their hips during times like these slip and fall while just walking down the driveway to pick up the morning paper.

“If you’re not steady on your feet, let somebody else go get your paper,” Zabel said, or perhaps your dog.