Heart disease is a leading cause of death in the United States. Influenza impacts as many as 45 million Americans each year, resulting in between 12,000 and 61,000 deaths annually, according to the Centers for Disease Control and Prevention. So what happens when these two conditions intersect? We asked Mark O’Shaughnessy, MD, PPG – Cardiology, to share more about flu risk for patients with heart disease and the best tools for prevention.
Why is contracting the flu dangerous for those with heart conditions?
Several studies have shown a significant increase in cardiovascular complications with the onset of flu, such as a worsening of congestive heart failure or decompensation of arrhythmias. This could mean the patient has a loss of control of chronic atrial fibrillation (Afib) or even a myocardial infarction (heart attack).
A study published in 2020 that looked at over 80,000 patients over eight years demonstrated 12% of the patients had cardiac complications with the flu. A 2018 study demonstrated a six-fold increase in heart attack within a week of a flu diagnosis. Basically, the stress of influenza can result in decompensation of stable heart disease or even an increase in the incidence of heart attack, likely an inflammatory pathophysiology.
Are there certain conditions that pose a greater risk?
Likely congestive heart failure patients have the highest risk for developing complications with the flu, but any patient with heart disease has an increased risk for complications. The additional stress from a respiratory infection (which is what influenza is at a fundamental level) puts additional stress on the cardiovascular system. It’s all connected.
Is contracting influenza dangerous for your heart if you don’t have a preexisting heart condition?
Without documented heart disease there is likely less of a chance for significant cardiac complications, however some heart disease is occult (silent) and manifests from significant stress, like the type generated by influenza. Also, patients can get a viral cardiomyopathy, which is inflammation of the heart, that causes congestive heart failure related to the viral illness (influenza).
What can those with heart conditions do to protect themselves from the flu?
Everyone should get a flu vaccine! This is especially important for those with preexisting heart disease as outlined above, but influenza can still be a very serious illness even in those without documented prior disease, so vaccination is important. An ounce of prevention is worth a pound of cure. Thorough hand washing and mask wearing are also important measures that can be used to prevent infection.
When should someone seek emergency care?
Individuals should seek emergency medical attention if they have progressive symptoms such as shortness of breath, fast heart rates that are causing symptoms and, of course, with any chest pain. Patients with chest pain need to call 911 and never drive themselves to the hospital.
