In colder regions of the country, winter weather poses more than just risks of hypothermia. Many people are unaware that risk of heart attack also increases when the temperature drops. In the cold, blood vessels tend to constrict in an effort to conserve body heat. As a result, blood pressure increases and the amount of oxygen that can get to the heart decreases. Couple that with strenuous winter activity — like shoveling snow — and you have a recipe for heart attack in susceptible people. For people at increased risk of of heart disease, experts recommend avoiding strenuous cold-weather activity, and they should be aware of heart attack symptoms to ensure immediate response if one occurs.
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