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Cardiovascular (Heart) Disease


Hot weather increases the workload on your heart and the extra demand for oxygen can increase symptoms in people with cardiovascular diseases. Here are some tips to stay healthy this summer:

  • Keep hydrated by drinking plenty of water or other sugar-free drinks. If you've been told to restrict your fluid intake for medical reasons you should speak to your GP about safe levels for you to drink.  Avoid drinking alcoholic or caffeinated drinks as these can make you more dehydrated.
  • Eat fresh foods, particularly salads and fruit with high water content.
  • Keep cool indoors and keep the windows closed while the room is cooler than it is outside. Open windows at night when the air is cooler.
  • Wear appropriate clothing and sunscreen.
  • Stay out of the heat in the hottest part of the day, usually between 11am and 3pm.
  • Avoid excessive physical activity. If it makes you sweat, don’t do it.


Heatstroke can happen if you get dehydrated as a result of too much sun and the body starts to shut down. The symptoms of heatstroke can develop over several days and can be dangerous for those with cardiovascular diseases. Losing too much body fluid can increase your internal body temperature, which could be life-threatening if left untreated.

Symptoms of heat stroke include:

  • Sweating or cold clammy skin
  • Dizziness and fainting
  • Muscle cramps
  • Swollen ankles
  • Shallow or fast breathing
  • Nausea and vomiting.

The extreme heat that causes heatstroke also affects the nervous system. If heatstroke gets severe, it can cause other symptoms like:

  • Lack of co-ordination
  • Fits
  • Headaches
  • Vertigo
  • Restlessness or anxiety
  • Problems understanding or speaking to others
  • Hallucinations
  • Loss of consciousness.

Heatstroke is a medical emergency. If you, or anyone you know, displays these symptoms, dial 999 immediately.

For more information and advice, visit NHS Choices at, or ring NHS 111.