Here’s How Cold Weather Can Trigger a Heart Attack

Chilling fact: Every 40 seconds, someone in the United States has a heart attack, according to the American Heart Association. Although the life-threatening event can seem random, a study presented in August 2017 at the European Society of Cardiology Congress found that the average number of heart attacks per day was significantly higher during colder versus warmer temperatures.

Your heart needs oxygen-rich blood to function. A heart attack happens when a buildup of plaque — a mix of fat, cholesterol, and other substances — in your arteries breaks free. A blood clot forms around the plaque to either completely block or restrict blood flow to your heart. And freezing weather can ignite this painful process.

The Connection Between Your Ticker and Subzero Temps

“Cold weather, especially a very rapid change in the weather, is more likely to cause your blood vessels to constrict. If you have narrowing of the blood vessels already because of underlying heart disease and your blood vessels are constricted further, it restricts the amount of blood that’s getting to vital organs,” says Lawrence Phillips, MD, cardiologist and assistant professor of medicine at NYU Langone Health in New York City. In other words, cold weather can make heart attack more likely to happen.

Instead of triggering a full-blown heart attack, cold weather can also just minimize blood flow to the heart, causing chest pain (angina), which is a symptom of coronary artery disease. This is the main form of heart disease, a disorder of the blood vessels of the heart that can lead to heart attack.

In addition to coronary artery disease, cold weather can put a strain on your heart and circulatory system, affecting other forms of cardiovascular disease, too.

“If you have a diagnosis of heart failure or advanced valve disease, you have to be very careful when the weather changes to the colder side as well,” Dr. Phillips says.

Moreover, research presented in August 2015 at the European Society of Cardiology Congress in London showed that cold weather may also increase the risk of ischemic stroke in patients with atrial fibrillation, a heart rhythm disorder. Ischemic stroke — the most common type of stroke — occurs when ruptured arterial plaque causes a blood clot to block a blood vessel to the brain, cutting off its much needed blood and oxygen supply.

Sudden bouts of energetic activity, such as rushing around to get out of the cold or shoveling snow, in combination with chilly temperatures can put additional strain on the blood vessels that feed your heart or brain. This puts you at greater risk of having a cardiovascular event, especially if you’re usually sedentary.

Symptoms of heart attack include uncomfortable pressure, squeezing, fullness, or pain in your chest (angina) or other areas of your body and shortness of breath.

Stroke symptoms to watch out for include facial drooping, especially on one side, arm weakness, and difficulty speaking.

Cold Weather Cures for Preventing Heart Attack and Stroke

The good news? If you’re an average healthy person, the cold weather won’t increase your risk of a cardiovascular event, such as heart attack, stroke, or angina. Trouble is, you can have underlying coronary artery disease — the clogged arteries (atherosclerosis) that are the underpinnings of a heart attack and stroke — and not even know it. Cardiovascular disease doesn’t always have signs or symptoms. So you might not even know you have it until you have a heart attack or stroke.

Here’s what to do to reduce your risk of heart attack and stroke, especially in cold weather.

Get a checkup. “As you’re gearing up for winter, make sure your health is optimized,” Phillips says. In other words, the start of winter is a good time for a routine physical to make sure your heart can take the cold. If you have a diagnosis of coronary artery disease, heart failure, or advanced valve disease, make sure to get the appropriate treatment and follow-up. You want to make sure your blood cholesterol and blood pressure are under control, too. High cholesterol and high blood pressure can increase the risk of heart attack and stroke.

Cover your mouth. If you have heart disease, heart failure, or advanced valve disease, cover your nose and mouth with a scarf before going outside. “Wearing a scarf allows the air to naturally get warmed before it comes into your body,” Phillips says. “It won’t be such a shock to your body.”

Bundle up. To avoid getting too cold, which may increase the risk of heart attack, don’t forget to wear a hat, gloves, and multiple layers, which can help you stay warm by trapping air and body heat. But don’t overdo it. If you get hot, take off a layer. And remember to stay well hydrated.

Know your body. If you notice heart-related symptoms, such as chest pain, shortness of breath, feeling winded, or fluttering in your chest, see your doctor. “If something feels different than normal, don’t ignore it. Get evaluated,” Phillips says. Similarly, if you’re having chest pain at rest, and it’s a new symptom, you need an immediate evaluation. Call 911. “Never drive yourself to the emergency department,” he says.

Don’t let snow-shoveling kick off your workout. “If you haven’t been exercising regularly, snow shoveling isn’t the best idea,” Phillips says. Because snow can be heavy, shoveling may be a lot more physical activity than you’re used to, which can put a strain on your heart. Anybody with a chronic medical condition, not just heart disease, should talk to their doctor about whether snow shoveling is a good idea. “I tell my patients with underlying heart disease not to shovel snow,” Phillips says. “But they can use a snow blower.”

Get a flu shot. A study published in October 2013 in The Journal of the American Medical Association found that a flu shot was associated with a lower risk of cardiovascular events; getting a flu shot may reduce your risk of heart attack or stroke. Likewise, reduce your chances of getting the flu by staying away from people who are sick, washing your hands with soap and water often, and avoiding touching your eyes, nose, and mouth.