The temperatures are rising. The body does all kinds of things to cool down. This affects what happens to the heart. For cardiovascular patients, the effect of heat is significant and creates additional challenges.
The heat means that your heart has to work much harder, explains Hermien Kalkman. She is a medical information advisor at the Heart Foundation. “To dissipate heat, you sweat more, because sweat on the skin provides cooling when it evaporates. Blood vessels in the skin also become wider, so that the heart can pump more blood and the body can lose more heat through the skin.”
But because of the extra space in the dilated vessels, the heart pumps less blood than normal with each beat. The blood also has less volume due to sweating. “That's why the heart has to work hard to get enough oxygen and nutrition everywhere in the body. If your heart is already working less well, it won't work so well. You can then become short of breath and tired, or get swollen ankles.”
Syrupy blood
Because the vessels are wider, the blood pressure drops. In addition, the blood has less volume due to sweating. Hermien Kalkman:“The fluid decreases, but the number of blood cells remains the same. This makes the blood more viscous than normal. Sometimes you even get clots in the blood that can cause a stroke or heart attack.”
Be careful with medicines
Staying cool is the most important advice. This certainly applies to the elderly and people who use certain medicines for heart problems or high blood pressure. “Pure liquids are an example of this”, Kalkman warns.
A water tablet helps to drain moisture. But when it's hot, this can get too much. “The water and salt balance is disturbed and there is a risk of dehydration and too little sweating. Complaints of dehydration are:headache, cramps, nausea or vomiting, exhaustion, dizziness, fainting and sometimes unconsciousness.”
Advice for cardiovascular patients
Drinking enough water and staying out of the sun is important for everyone. In this way, the body does not have to make extra effort to cool down, and you do not put an extra burden on the heart. Read here the tips for extreme heat and advice for heart patients.
