Snow shoveling in cold weather can be quite dangerous for your heart. (For Spectrum Health Beat)
Snow shoveling in cold weather can be quite dangerous for your heart. (For Spectrum Health Beat)

So far this winter, Michiganders have lived in a snow globe. And winter is far from over.

Hospital visits for heart events increase a whopping 20 percent in the week following a snow storm.

Commit to not becoming a statistic. Whether you know you have heart disease, have had a heart attack, or have risk factors like being a smoker, overweight or diabetic, the risk is real. Here are some reasons to think twice before heading into the white stuff.

The dangers

A shovelful of wet snow weighs about 15 pounds. At 12 shovelfuls per minute, you’ll have tossed nearly a ton of snow in 10 minutes.

Duane Berkompas, MD, is a Spectrum Health cardiologist well acquainted with winter heart attacks. He said there are three issues that come into play with cold weather and activities like shoveling.

  1. Blood clots. “Studies have confirmed there is a greater tendency to form them when a person is exposed to cold temperatures,” Dr. Berkompas said. A heart attack is caused by the rupture of a blocked artery. Blood clots form at the area of blockage. If you have risk factors and add cold, the likelihood of a clot goes up.
  1. Constriction of blood vessels. “More importantly, the second thing is that we know cold tightens blood vessels,” he said. This constriction puts an extra burden on the heart and lungs.
  1. Shoveling stress. Dr. Berkompas noted that this risk is less of an issue of cold, but more a higher level of exertion on top of cold. “Shear stress is a sudden acceleration of blood flow, such as from a strenuous activity like shoveling,” he said. “The sudden acceleration can cause an immediate risk of tear.” Often, high-energy activities out in the cold call for more fitness than a person might be fit to attempt, whether it’s shoveling or dragging a toboggan up a long hill. It’s not one thing, but several. The cumulative physiological responses cause a big risk: high output activity plus cold plus heart disease or risk factors.

The risk factors

“We want people to exercise if they have heart disease, but there are situations such as these that are too potentially detrimental,” Dr. Berkompas added.

Use common sense. If you have any of the below risk factors, then snow shoveling or strenuous outdoor activity in cold may not be safe.

  • Smoker
  • Uncontrolled high blood pressure
  • High cholesterol
  • Diabetes
  • Family history of heart attack or heart disease
  • Overweight

Dr. Berkompas noted that those with heart disease or pre-existing heart issues are aware they are at higher risk “yet many who have significant risk have no idea they have blockages or disease effects going on.” He said these are people cardiologists tend to see on an emergency basis.

“It’s easy to think that symptoms of heart attack are just due to the exertion, especially when they subside afterward,” Dr. Berkompas said.

He said it is not normal to have any of these symptoms from exerting yourself in cold weather:

  • Shortness of breath
  • Lightheadedness or dizziness
  • Heaviness, pressure or tight feeling in the chest
  • Aching or heavy arms
  • Jaw discomfort

“If you have any of these, even if they go away, see a doctor,” Dr. Berkompas urged. “The ‘going away’ of symptoms just means you stopped; it does not mean there is not a serious problem underway. Use common sense and don’t assume it was nothing. Wear layers of clothing to keep body temperature steady. Don’t go beyond your regular fitness level. And, if in doubt, simply don’t do it.”