[Anchor]

We also bring you health-related news to watch out for in this kind of weather. People tend to think of myocardial infarction as a condition to watch out for mostly during the cold winter. However, it is said to be even more dangerous in hot weather.

Reporter Han Sung-hee has the details on how to prevent it.

[Reporter]

At dawn three days ago, a woman in her 80s suffering from severe dehydration was rushed to the emergency room.

It was a myocardial infarction, in which the coronary arteries supplying blood to the heart were blocked.

[Lee Jin-ho / Professor of Cardiology, Kyung Hee University Hospital: (The patient) stayed in a hot environment for a long time and lacked energy, making her unable to drink enough water. Her dehydration symptoms were extremely severe, and due to the dehydration....]

During heatwaves like these, our bodies sweat to lower body temperature, which leads to dehydration.

When bodily fluids are depleted, the blood becomes sticky, forming blood clots commonly known as thrombi, which can block blood vessels and cause myocardial infarction or stroke.

[(Is this part that looks like this blocked?) Yes. The black area with whitish filled parts in between all show blood clots. The blood should flow smoothly through the vessel, but it is blocked.]

This is why myocardial infarction is just as frequent during heatwaves as it is in winter, when blood vessels suddenly constrict in cold air.

According to statistics from the Health Insurance Review and Assessment Service, the cumulative number of acute myocardial infarction patients over the past five years has been more than 13,500 higher in summer than in winter.

In 2018, when the number of heatwave days reached 31, the burden of cardiovascular and cerebrovascular diseases surged more than fourfold compared to the years before and after, which had about half as many heatwave days.

Older adults who sweat during heatwaves but often fail to feel thirsty are at especially high risk.

[Ryu Jeong-bun / Dongdaemun-gu, Seoul: I usually don't drink water. I don't drink much. About a cup a day?]

[Seo Sang-ho / Dongdaemun-gu, Seoul: You need to drink a lot of water, but I just don't feel like drinking much.]

[Lee Jin-ho / Professor of Cardiology, Kyung Hee University Hospital: If you remain exposed to a hot summer day continuously, you can think of it as being in a state similar to running a marathon all day long. By the time you feel thirsty, it is very likely that the water in your body has already escaped....]

Before feeling thirsty from the heat, it is advisable to drink water frequently—a cup every hour or two rather than a large amount at once.

(Camera Journalist: Yang Hyun-chul | Video Editor: Park Na-young | Designer: Park Tae-young)