Extreme Heat & Your Heart: What Californians Need to Know

As temperatures rise, Dignity Health raises awareness of increased heart attack, stroke and heat-related illness risks due to extreme heat.

Santa Maria, California - July 14, 2026 - As temperatures climb across California and heat advisories become more common, Dignity Health is urging residents to recognize the serious impact extreme heat can potentially have on the heart, particularly for older adults and those living with cardiovascular disease.

When temperatures soar, the heart must work harder to keep the body cool. For some individuals, that added stress could increase the risk of heat-related illness, heart attack, stroke and other cardiovascular complications.

"Many people think of heat exhaustion and dehydration during a heat wave, but fewer realize that extreme heat can place significant strain on the heart," shares Kirsten Shaw, MD, Cardiologist at Dignity Health Coastal Valley Health Center in Santa Maria. "As the body works to cool itself, the heart pumps harder and faster. For individuals with underlying heart conditions, that additional workload can become dangerous."

High temperatures can potentially increase heart rate, reduce blood volume through dehydration and disrupt electrolyte levels that help regulate normal heart function. These factors may place vulnerable individuals at greater risk for serious health complications.

Those at highest risk may include:

• Adults age 65 and older

• Individuals with heart disease, heart failure, high blood pressure or a history of stroke

• People taking medications such as diuretics, beta-blockers or ACE inhibitors

• Outdoor workers, athletes and first responders who spend extended periods in the heat

Dignity Health encourages Californians to take the following steps to support their safety:

• Stay hydrated by drinking water throughout the day, even before feeling thirsty

• Seek air-conditioned environments whenever possible

• Limit strenuous outdoor activities during peak heat hours, typically between 10 a.m. and 4 p.m.

• Wear lightweight, light-colored clothing and take frequent breaks in shaded areas

• Talk with your healthcare provider about how heat may affect medications or existing health conditions

• Check on older family members, neighbors and others who may be more vulnerable to heat-related illness

• Residents should also be aware of warning signs that could require immediate attention. Symptoms such as dizziness, nausea, rapid heartbeat, confusion, fainting or difficulty breathing may indicate a serious heat-related emergency.

"Extreme heat is more than a seasonal inconvenience - it can also be a health threat," Dr. Shaw said. "By staying hydrated, limiting heat exposure, and recognizing the warning signs early, people may significantly reduce their risk and protect their heart health."

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About Dignity Health Pacific Central Coast Health Centers (PHC)

A service of Dignity Health, Pacific Central Coast Health Centers (PHC) is a non-profit Community clinic organization of nearly 50 health centers located along the coast primarily from Templeton to Ventura and also in Bakersfield. Our experienced physicians and advanced practice providers offer a wide range of primary and specialty care services. PHC is a part of Dignity Health Central Coast's award-winning network of outstanding hospitals, urgent cares, imaging centers, laboratories and post acute services. Learn more at commonspirit.org/phc.

About Dignity Health California

Dignity Health California is a nonprofit network of over 9000 physicians, more than 35,000 employees, 29 acute care hospitals, and 200-plus care-centers, including community hospitals, urgent care, surgery and imaging centers, home health, and primary care clinics. Dignity Health California provides award-winning care to communities in five primary markets across the state: North State, Sacramento, Central Valley, Central Coast and Southern California.

Dignity Health is a member of CommonSpirit Health, one of the nation's largest nonprofit Catholic healthcare organizations, dedicated to providing compassionate, high-quality, and affordable patient-centered care with special attention to the poor and underserved. Learn more at commonspirit.org.