How Flu Affects the Heart

If you have heart disease, the flu – and most respiratory diseases – can lead to serious complications, even if your condition is well managed.

Flu can increase the chance of:

• Pneumonia
• Heart attack
• Stroke
• Inflammation – or swelling – of the heart muscle (myocarditis) or lining around the heart (pericarditis)
• Worsening heart disease or other health problems 
• Hospitalization or even death

Why? Flu can place extra stress on your body. It can quicken your heart rate, raise your body temperature, and ramp up your body’s fight or flight response, all of which make your heart work harder. The flu triggers inflammation, which can:

• Make your blood more likely to clot – blood clots are what can lead to heart attacks and stroke
• Cause plaque that builds up in the arteries to rupture
• Raise blood pressure
• Force the heart to pump harder, adding more stress to the heart

  Any of these can make a heart attack or stroke more likely, especially among people with heart disease, high blood pressure or diabetes. 

If you need more convincing, the flu vaccine carries additional heart benefits, too. Annual flu vaccination has been shown to:

• Lower the risk of heart attack, stroke and related deaths
• Reduce hospitalizations due to heart or flu-related complications  
• Protect those around you too!