Extreme Heat Strains Your Heart: AHA Warns of Rising Risks

As summer temperatures soar across the United States, the American Heart Association (AHA) is issuing a critical warning: extreme heat is not just uncomfortable—it can be deadly for your heart. According to the National Weather Service, heat is actually the leading weather-related cause of death in the U.S., surpassing hurricanes and tornadoes. A report in the Journal of the American Medical Association found that more than 2,300 people died from heat exposure in the U.S. in 2023, while research in the AHA’s journal Circulation projects that heat-related cardiovascular deaths could more than double in the coming decades. Dr. Manesh R. Patel, volunteer president of the AHA and chief of cardiology at Duke Health, explains that heat forces the heart to work harder: heart rate increases, blood vessels expand, and the strain can become dangerous quickly—especially for people with heart disease, and even those who are otherwise healthy.

The AHA outlines how heat stresses the body: sweating leads to fluid loss and dehydration, while the heart pumps more blood to regulate temperature. To stay safe, they recommend avoiding peak heat hours (noon to 3 p.m.), dressing in lightweight clothing, staying hydrated with water (avoiding alcohol and caffeine), and taking breaks in cool spaces. Recognizing warning signs is crucial. Heat exhaustion symptoms include headache, cool pale skin, fast weak pulse, dizziness, muscle cramps, and nausea. If these occur, slow down, move to a cooler place, and rehydrate. Heat stroke is a medical emergency—call 9-1-1 if body temperature exceeds 103°F, skin is hot and red, pulse is rapid and strong, or confusion or loss of consciousness occurs. The AHA emphasizes that physical activity remains vital for heart health, but suggests shifting exercise to early morning or evening, or moving indoors to air-conditioned spaces. For more tips, visit heart.org.