The University of Ottawa Heart Institute saw an uptick in heart attack patients Monday night directly related to shovelling snow, a local cardiologist says.

Monday's storm brought 48 cm of snow to Ottawa in a single day. It was the snowiest day in the city since 2016 and snow shovels were out in force.

Unfortunately, as cardiologist Dr. Hassan Mir of the Divisions of Cardiology and Cardiac Prevention and Rehabilitation at the University of Ottawa Heart Institute says, the task of shovelling sent several people to hospital.

"We've had several not just minor heart attacks, but several major heart attacks that have required emergency treatment with stenting and we saw several of them overnight," Mir told Newstalk 580 CFRA. "Several directly related to people shovelling their driveway and having to call 911."

Speaking on Ottawa Now with Kristy Cameron, Mir said snow shovelling is a perfect storm of risk factors for cardiac issues.

"It's a combination of the fact that it's very cold outside, which causes constriction or narrowing of the blood flow to the entire body but especially the heart and, at the same time, you're doing heavy lifting, which drastically increases the amount of workload of the heart by driving the heart rate and blood pressure up," he explained. "That results in a bad mismatch of a lack of blood flow and an increased requirement of blood flow."

While Monday's storm was unique in terms of its sheer size, Mir said these issues are common every winter.

"Any sort of stressor to the heart can cause extra undue stress on the coronary arteries—that is, the arteries in the heart—and that subsequently causes a small tear and can cause that massive heart attack. We see this every year in the winter and especially after a large snowstorm," he said.

Men over the age of 55, smokers, people with high blood pressure or high cholesterol, and people with diabetes are at increased risk of severe illness from shovelling, Mir said, but even people without a history of heart problems can end up suffering a heart attack while shovelling.

"Speaking of the last 24 hours, at least three of the patients have never had any cardiac issues and then have now come in while shovelling snow and had their first heart attack and first issue with the heart," he said.

The weight of the snow does make a difference, Mir said, though the activity of shovelling can still be strenuous regardless.

"If it's fluffy and soft, there's a lot less weight and a lot less workload on your body, your muscles, and your heart, but if it's a heavy and wet snow, that typically makes it much worse," he said. "Our advice is usually don't lift the snow; push it to the side rather than heavily lifting it."

And if you experience any symptoms, seek help immediately.

"If you feel chest discomfort, shortness of breath, dizziness, light-headedness, palpitations, please stop, call 911, call for help," Mir said. "We say there's an increase in hospitalizations, but that's by no means a suggestion that you shouldn't call for help. We always have room for our patients, so please, if you're feeling symptoms, seek medical attention immediately."

Here are some tips from the Public Health Agency of Canada to keep you safe while shovelling:

  • Warm up. Give your muscles the chance to get ready for the exercise you’re going to put your body through. Do some basic stretches to limber up and increase circulation.
  • Don’t dig on a full stomach. Give yourself some time to digest before picking up a shovel, since exercising right after a meal can cause strain on the heart.
  • Shovel with a buddy. If possible, get some help clearing the snow. It will cut down on your shovelling and let you keep an eye on each other.