Extreme Heat: An Overlooked Risk for Cardiovascular Disease

Rising temperatures due to climate change are harming cardiovascular health. Experts emphasize that the frequency, intensity, and duration of heat waves have increased markedly over the past 70 years, creating a major public health problem in terms of cardiovascular disease. Europe is the fastest-warming continent in the world, and more than 60,000 heat-related deaths were reported in the summer of 2022 alone.

According to meta-analysis data, every 1°C rise in temperature above local threshold values increases cardiovascular mortality by 2.1%. In particular, the risk of stroke (3.8%) and acute coronary syndrome (3.5%) rises markedly. Arrhythmias, sudden cardiac death, and out-of-hospital cardiac events are also more common in hot weather.

The harmful effects of heat arise through mechanisms such as peripheral vasodilation, tachycardia, dehydration, increased blood viscosity, inflammation, and a tendency toward blood clotting. The combination of air pollution and heat increases the risk even further. High nighttime temperatures and sudden temperature changes are also important factors that raise the risk of myocardial infarction (heart attack).

The authors state that expanding green spaces, early warning systems, heat action plans, and cardiologists informing their patients about heat-related risks are vitally important.

Conclusion

Climate change is no longer just an environmental problem; rising temperatures are poised to become one of the most important and preventable determinants of cardiovascular morbidity and mortality in the years ahead.

Source

Schneider, A., Münzel, T., & Sanchez, G. (2026). Heat stress and cardiovascular health: a multi-faceted and under-recognized emergency. *European Heart Journal*, *47*(22), 2718–2720. https://doi.org/10.1093/eurheartj/ehag084