Expert advice on protecting your heart in the heat

As the forecast for the coming days shows that Ireland’s heatwave is set to continue, Irish Heart Foundation’s National Heart and Stroke Helpline Nurse, Bernadette Bergin, has some expert advice for those living with heart disease on staying well in the heat.

In hot weather we sweat to cool down. This means we lose more fluid than usual from our bodies.

Losing too much fluid by sweating profusely can cause our blood pressure to drop and make our hearts beats faster. Our heart and circulation have to work much harder to try to keep our bodies cool. For most of us this is not a problem. We just need to drink plenty of fluids, ideally water or other sugar-free drinks, which will keep us from getting dehydrated.

However, for anyone with heart disease or who has had a stroke, the really hot weather can put an extra strain on the heart and circulation. It is therefore especially important to stay cool and well hydrated.

Some people with heart disease may start to get angina again, or their angina may worsen; so, keep cool and keep hydrated to help prevent this.

For those with heart failure, where your heart doesn’t pump as well as it should, it’s particularly important to stay cool. You need to keep hydrated, but if you’ve been told to restrict your fluid intake, you need to look at other ways to keep cool.

Some medicines like a beta blocker, can constrict the blood vessels and reduce blood flow to the skin, making it more difficult to keep cool. Other medicines such as diuretics, known as water tablets, help to rid your body of salt and water to lower blood pressure and swelling and improve the function of your heart. This can lead to dehydration, as a common side effect of this medicine is that it causes an increased need to pass urine. If you take a water tablet and start to feel dizzy or light-headed, you must let your doctor know. Your doctor may reduce or even stop the water tablet for a while if necessary, until you feel better, or the weather gets cooler.

Reduce the amount of physical exertion you do in the heat, especially if you’re unfit, are new to exercise, have a heart condition or have had a stroke. Both the physical activity itself and the air temperature can increase your core body temperature, putting extra strain on your heart and circulation, as previously mentioned.

Here are some things you can do to keep cool

• Avoid over-exerting yourself physically.
• Avoid too much alcohol or caffeinated drinks. These can cause you to lose more body fluids.
• Eat more cold foods, like salads and fruit and vegetables with a high-water content. Some examples are melons, cucumbers, strawberries, broccoli, cabbage, celery and tomatoes.
• If you are out and about, try to keep in the shade, wear a hat and apply sunscreen.
• Keep well-hydrated, unless you’ve been told to restrict your fluid intake. If so, then discuss this with your doctor.
• Stay out of the sun during the hottest part of the day, usually between 11 am and 3 pm.
• Try to keep your home as cool as possible. For example, draw curtains and blinds during the daytime.
• Wear light-weight, light-coloured, loose-fitting clothing. White clothes reflect heat away from our bodies. Black clothes absorb more heat.

The HSE has issued advice on what to do if your water is restricted as well as advice for the general public on the hot weather.