Heart Health
Why people faint: From common to very rare causes
About one in seven fainting episodes stems from heart‑related problems.
There’s one simple reason behind all fainting episodes — the brain isn’t getting enough blood. But there are many possible underlying causes, ranging from common, usually harmless issues to rare, potentially serious problems.
"Fainting always should be taken seriously, so be sure to get evaluated by a doctor if you faint, particularly if you have any history of heart problems," says Dr. Jeremy Ruskin, founder of the arrhythmia service at Harvard-affiliated Massachusetts General Hospital. But even people without any previous heart issues aren’t off the hook. Sometimes syncope (the medical term for fainting) is the first sign of a previously undetected heart condition, he says.
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About the Author
Julie Corliss, Executive Editor, Harvard Heart Letter
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