Extreme Heat Limits Oxygen Delivery in People With Heart Problems. This is especially concerning with climate change making summer temperatures more extreme.
https://jamanetwork.com/journals/jama/fullarticle/2820922?guestAccessKey=f2e9bfdf-c12b-44bb-ac30-65f10349ec03&utm_source=silverchair&utm_medium=email&utm_campaign=article_alert-jama&utm_content=olf&utm_term=070524&adv=001205050228