In scorching hot weather, one must be cautious of acute myocardial infarction caused by dehydration. Acute myocardial infarction occurs when the coronary artery, which supplies blood to the heart muscle, suddenly gets blocked, damaging the heart muscle. The initial mortality rate is 30%, and even after arriving at a hospital for treatment, 5~10% can die, making it very dangerous. Although myocardial infarction is known to occur mainly in winter, it can be just as dangerous in summer.
According to the Health Insurance Review & Assessment Service (HIRA) on the 10th, the number of patients treated for acute myocardial infarction in hospitals increased by 21%, from 118,010 in 2019 to 142,746 last year (up to November). During last summer, from June to August, there were 100,645 cases of acute myocardial infarction. This is similar to the previous winter (December 2023 to February 2024), which had 101,661 patients. The total number of patients in a month is higher than the annual number of patients because some patients visit hospitals multiple times in a year.
Typically, myocardial infarction occurs in the cold winter when blood vessels constrict. In summer, dehydration is the issue. Our body sweats in the heat, trying to release heat to lower body temperature. When excessive moisture leaves the body, blood viscosity increases, making the blood sticky. This can lead to blood clots, called thrombosis, which can block the coronary arteries and result in acute myocardial infarction. According to the American Heart Association, when the temperature rises above 32 degrees Celsius, the number of myocardial infarction patients increases by 20%.
Myocardial infarction initially presents with a nagging and squeezing chest pain as a precursor symptom. There may also be difficulty breathing and cold sweat. However, summer myocardial infarction uniquely exhibits symptoms of dizziness. Patients sometimes visit a hospital late, thinking it's just the heat, and miss timely treatment.
When suspected symptoms appear, one should minimize movement and call 119 to go to the hospital immediately. Driving oneself can be dangerous as well. Using nitroglycerin (a vasodilator) placed under the tongue is also an option. The Korea Disease Control and Prevention Agency noted, "To reduce heart necrosis, one must arrive at the hospital within 6 hours of onset, and to recover heart muscle, one must arrive within 12 hours," adding that "one should not waste time at pharmacies or traditional medicine clinics."
To prevent acute myocardial infarction in summer, it is essential to drink water frequently to maintain smooth blood circulation. Caution is advised as excessive beer consumption in the heat can exacerbate dehydration due to alcohol. Showering with cold water can raise blood pressure and increase heart rate, which can put strain on the heart. It is better to mix in lukewarm water when showering.