The #1 Cause of Heart Failure, According to Science

Heart failure. The idea is scary. After all, no organ is more critical—the heart is tasked with pumping the oxygen-rich blood throughout the body that keeps us alive. Yet millions of people face the prospect of heart failure each year. Here's exactly what heart failure is, what causes it, according to science, and how you can prevent it. Read on to find out more—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.

Heart failure doesn't mean your heart has immediately stopped working. "Heart failure is a condition that develops when your heart doesn't pump enough blood for your body's needs," explains the National Institutes of Health. "This can happen if your heart can't fill up with enough blood. It can also happen when your heart is too weak to pump properly."

Data from the Centers for Disease Control & Prevention indicates that about six million people in the U.S. have heart failure. It's a serious condition that requires treatment, and it currently has no cure.

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According to the NIH, the primary cause of heart failure is a previous condition that damages the heart. This can include coronary artery disease, high blood pressure, or a prior heart attack. 

The most common cause of coronary artery disease is atherosclerosis, or a buildup of plaque in the arteries, the Mayo Clinic says. Unhealthy lifestyle habits, such as a poor diet, physical inactivity, being overweight and smoking, can lead to atherosclerosis.

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Heart failure can affect either the right or left side of the heart, and symptoms vary depending on which side is affected. People with left-sided heart failure often have the following symptoms: 

• Trouble breathing
• Cough 
• Fatigue 
• Weakness 
• Bluish fingers or lips  
• Tiredness and difficulty concentrating 
• Inability to sleep lying flat

People who have right-sided heart failure may report the following symptoms: 

• Nausea or loss of appetite 
• Abdominal pain
• Swelling in the ankles, feet, legs, abdomen, or veins in the neck 
• Frequent urination 
• Weight gain 

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To prevent heart failure and heart disease, experts say one of the most important things you can do is to manage conditions that raise your risk of heart failure, such as diabetes and hypertension (high blood pressure).

And to keep your heart in good working order, the NIH also recommends following a heart-healthy lifestyle (choosing a healthy diet, maintaining a healthy weight, getting regular exercise, and quitting smoking), limiting or avoiding alcohol, and avoiding illegal drugs.

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"COVID-19, the disease caused by the SARS-CoV-2 coronavirus, can damage heart muscle and affect heart function," says Johns Hopkins. "There are several reasons for this. The cells in the heart have angiotensin converting enzyme-2 (ACE-2) receptors where the coronavirus attaches before entering cells. Heart damage can also be due to high levels of inflammation circulating in the body. As the body's immune system fights off the virus, the inflammatory process can damage some healthy tissues, including the heart." So follow the fundamentals and help end this pandemic, no matter where you live—get vaccinated ASAP; if you live in an area with low vaccination rates, wear an N95 face mask, don't travel, social distance, avoid large crowds, don't go indoors with people you're not sheltering with (especially in bars), practice good hand hygiene, and to protect your life and the lives of others, don't visit any of these 35 Places You're Most Likely to Catch COVID.