Protecting Your Heart During Extreme Heat

As summer temperatures climb, protecting your heart health is more important than ever. While most people associate extreme heat with dehydration or heat exhaustion, fewer realize just how much strain high temperatures can place on the heart, especially for older adults and those with existing cardiovascular conditions.

“Extreme heat is more than just uncomfortable. It can be dangerous, particularly for your heart,” said Dr. Mahesh Raju, an interventional cardiologist with Advocate Health Care. “By understanding how heat affects your body and taking practical steps to stay cool and hydrated, you can reduce your risk and enjoy the summer safely.”

When temperatures rise, your body works harder to stay cool. Blood vessels widen, and your heart pumps more blood to the skin to release heat. At the same time, sweating causes fluid loss, which can reduce blood volume.

This combination forces your heart to work overtime. For healthy individuals, this added strain is usually manageable. But for people with heart disease, high blood pressure, or a history of stroke, it can increase the risk of complications such as dehydration and electrolyte imbalances, irregular heart rhythms, worsening of heart failure symptoms and heat exhaustion or heat stroke.

In extreme cases, hot weather has been linked to an increase in heart attacks and cardiovascular-related deaths.

While everyone should be mindful during extreme heat, some groups face higher risks. That includes adults over age 65, people with heart disease or high blood pressure, individuals taking medications like diuretics or beta blockers, people who work outdoors or exercise in the heat and those without access to air conditioning.

“Heat-related stress on the heart can show up in subtle ways,” said Dr. Raju. “Symptoms to watch for include unusual fatigue or weakness, shortness of breath, dizziness or lightheadedness, rapid or irregular heartbeat and swelling in the legs or feet.”

He offers the following tips for keeping your heart healthy in the heat:

Check the air quality index: Heat waves often bring with them poor air quality, as air moving in from other regions can bring in pollutants, and poor air quality can trigger cardiovascular events. Wildfires are much more common during extreme heat, significantly impacting air quality. Check your area’s air quality before heading outside. Levels under 50 are generally considered safe.

Stay hydrated: Dehydration and electrolyte imbalance can happen much more quickly in warm temperatures, which can be especially serious among those with heart disease. Pay close attention to your water and electrolyte intake during hot weather.

Wear sunscreen and wear appropriate clothing: Apply a broad spectrum SPF of at least 30 and be sure not to miss any areas of the body exposed to the sun. Wear light-colored, loose-fitting clothing, sunglasses, a heat, and any other protective materials to keep the sun off of your skin.

Stay indoors: Avoid the warmest points of the day, which is also when the sun’s rays are the most damaging – between 10 am – 2 pm. If you’re heading outdoors in the heat, consider doing so in the early morning or evening.

Listen to your body: If you feel any signs of your body straining in the heat, such as shortness of breath or more fatigue than normal, get inside and stay there. Do not ignore any indication that the heat is worsening your heart disease.

Know the warning signs of an emergency: Chest pain, dizziness, rapid heartbeat, headache, extreme fatigue, and passing out are some of the most common signs something is wrong. If you or someone else experiences any of these symptoms, call 911 for prompt medical treatment.