Your heart in the heat

Excessive heat can be dangerous in many ways, but it’s especially dangerous for a certain group of people.

It’s a natural process.

If it’s hot outside, the body will respond in order to cool itself.

On those hot days, though, the body’s response can put significant strain on the heart. And if the heart is already in a weaken or compromised state, that strain can lead to other potential serious issues affecting someone’s overall health.

“Our hearts play a large and crucial role in cooling our bodies on hot, even warm days,” said Dr. Melissa Ianitelli, a McLaren Oakland cardiologist. “And of course, the hotter it is, the more the heart has to strain. If the heart is already compromised in any way, any additional strain raises the risk of further complications and potential worsening health issues.”

A cooling heart

There are two aspects to cooling the body in which the heart is considered.

The first is that more blood is pumped to the skin to help it cool, causing the heart to pump faster and harder.

The other is that the sweat cooling the body pulls sodium, potassium and other minerals from the body. These elements and minerals are important to muscles’ — like the heart — ability to contract (or in the heart’s case, pump) and for nerve transmission.

While most people can tolerate the added strain, others should exercise caution, especially those:

  • Recovering from a heart attack, or have previously suffered a stroke
  • Have been diagnosed with heart disease
  • Have narrowed arteries
  • Taking certain medications (talk to your doctor)
  • Diagnosed with Parkinson’s, Alzheimer’s or diabetes

Be cool

Signs of heat illness include:
  • Excessive thirst
  • Weakness
  • Headache
  • Loss of consciousness
  • Nausea and vomiting
  • Muscle cramp
  • Dizziness
  • Confusion
  • Rapid heart rate
  • Fatigue

Once signs of heat illness begin to appear, get out of the sun and heat, and find a cool place.

Heat stroke is a medical emergency. Call 911 if someone begins to show symptoms.

  • Body temperature of 103 degrees or greater
  • Strong, quick pulse
  • Headache
  • Dizziness/Nausea
  • Confusion
  • Loss of consciousness

When the temps are high, take simple preventive measures to avoid heat illness.

  • Stay hydrated throughout the day by drinking water steadily, don’t wait until you’re thirsty. Muscle cramping may be an early sign of heat-related illness.
  • Avoid caffeine and alcohol, which cause us to lose water more rapidly.
  • Take frequent breaks in the shade or indoors in an air-conditioned space. Do not rely on a fan as your main cooling device during an extreme heat event.
  • Wear loose fitting, lightly colored and lightweight clothes.
  • Minimize use of heat-generating appliances like stoves or ovens.
  • Do not exercise outdoors. If you must exercise outdoors, only exercise in the early morning hours, before 8 a.m.
  • Take cool showers or baths to cool down.


Emergency care at McLaren Oakland & McLaren Clarkston

Call 911 for life-threatening emergencies. Make an appointment for emergency care at McLaren Clarkston at

Click here

Heart care at McLaren Oakland

Learn more about cardiovascular care and make an appointment with a McLaren Oakland cardiologist.

Click here