Is it possible to have a heart attack and not even realize it?

The short answer is yes. As strange as it may sound, it is possible to have a heart attack with symptoms so mild or unexpected that they are either mistaken for something else (like heartburn or a panic attack) or go completely unnoticed.

A classic heart attack has clear symptoms — primarily chest pain, tightness or squeezing. A silent heart attack, known as a silent myocardial infarction, may not have that same sensation but may have symptoms like dizziness, weakness or indigestion that either intensify or gradually disappear.

“People who have a silent heart attack may dismiss the symptoms as being caused by something else, which makes sense because what they feel doesn’t match what they’ve understood to be classic heart attack symptoms,” said Devin Loewenstein, MD, a cardiologist with Endeavor Health Medical Group.

Silent heart attacks aren’t as common as heart attacks with classic symptoms. The American Heart Association reports that of the 805,000 estimated heart attacks each year in the U.S., about 170,000 are silent heart attacks.

While the symptoms may not be as intense as a classic heart attack, they can be just as dangerous. Many who have silent heart attacks aren’t aware that they had a heart attack, so they don’t seek medical care and their underlying disease goes untreated.

Having a silent heart attack increases the risk of having another heart attack, which could lead to complications such as heart failure or even death. While the risk factors for silent heart attack are the same as those for a classic heart attack, women, the elderly, and people with diabetes are more likely to experience a silent heart attack.

Sometimes people mistake a silent heart attack for a panic attack, which can have similar symptoms.

Classic heart attacks often have one or more of these common symptoms:

  • Squeezing chest pressure, pain or heaviness
  • Pain in the jaw, neck, arm, shoulder or back
  • Shortness of breath

Silent heart attacks may feel like:

  • Indigestion, nausea or vomiting
  • Muscle soreness in the chest or upper back
  • Excessive fatigue
  • Flu-like symptoms
  • Light-headedness
  • Anxiety or feeling impending doom
  • Cold sweat

If you suspect you may be having a heart attack, call 911.

If you think that you've had a silent heart attack in the past, talk to your healthcare provider.