Summer is here and temperatures are rising. It is more important now than ever to protect yourself from dehydration and heat-related illnesses, especially if you have a heart condition. According to the Center for Disease Control (CDC), hundreds of Americans die each year from heat-related conditions, many of which are preventable with early recognition and simple precautions.

Dr. Alexander Postalian, a cardiologist at The Texas Heart Institute Center for Cardiovascular Care, emphasizes, “Staying hydrated and recognizing early signs of heat-related illness can mean the difference between a quick recovery and a serious emergency—especially for those with cardiovascular concerns.”

Everyone Should Know and Understand the Difference Between Heat Exhaustion vs. Heat Stroke

Heat Exhaustion occurs when your body overheats due to excessive fluid loss and struggles to maintain a safe internal temperature.

Common symptoms of heat exhaustion:

• Heavy sweating
• Muscle cramps
• Weakness or dizziness
• Nausea or vomiting
• Fainting

What to do: Move to a shaded or air-conditioned space, remove excess clothing, and hydrate with water or an electrolyte-rich drink. Seek medical attention if symptoms persist or worsen.

Heat Stroke is a life-threatening condition that occurs when the body’s cooling system fails and core temperature rises above 103°F.

Urgent symptoms of heat stroke:

• Hot, red, dry skin with no sweating
• Rapid heart rate
• Severe headache
• Confusion or loss of consciousness

What to do: Call 911 immediately. While waiting for help, cool the person with ice packs, wet towels, or a cool bath.

 Who’s Most at Risk This Summer?

While everyone is vulnerable to heat, these groups need to be especially cautious:

• Heart failure patients and others with limited cardiac reserve
• Elderly adults and young children
• Outdoor workers and athletes
• Individuals with chronic illnesses or those taking diuretics

“People with cardiovascular disease can’t regulate body temperature as efficiently,” says Dr. Postalian. “They’re at higher risk for dangerous dehydration and heat stress.”

 

Understanding Sweat—and Why It Matters

Sweating is your body’s natural way to cool down. In dry heat, it evaporates quickly. But in humid weather, sweat lingers on the skin, making it harder to cool down and leading to greater fluid loss.

How Much Water Do You Really Need?

Proper hydration is a key defense against heat-related illness. Follow this basic hydration guide:

• Before exercise: Drink 16 oz of water 1–2 hours before activity
• During exercise: Sip 5 oz every 10–15 minutes
• After exercise: Rehydrate with 16 oz of water or an electrolyte drink

Important: If you have a cardiovascular condition such as heart failure, talk to your doctor. Some patients must monitor fluid intake closely to avoid fluid overload.

Tips for Exercising Safely this Summer

• Wear light, breathable clothing
• Avoid direct sun exposure—opt for early morning or late evening workouts
• Use cool (not ice-cold) water for better hydration
• Avoid salt tablets—they can make dehydration worse
• Choose water or electrolyte drinks over sugary beverages

Special Guidance for Heart Failure Patients

If you live with heart failure, avoid intense activity in extreme heat. Many take diuretics, which can further increase the risk of dehydration. If you have heart failure:

• Exercise indoors in air-conditioned spaces.
• Weigh yourself daily; a sudden drop in weight may indicate dehydration.
• Avoid non-air-conditioned homes or cars during heat waves.
• Try to keep the intensity of exercise moderate. If you cannot say complete sentences while exercising, it might be too intense – especially if you are living with cardiovascular disease.

 

Stay Safe, Stay Smart

Heat-related illness is largely preventable. By taking proactive steps—staying cool, hydrated, and informed—you can protect your health and enjoy everything Summer 2025 has to offer.

As Dr. Postalian reminds us, “when in doubt, take a break, find shade, and listen to your body.”