Heart disease is the leading cause of death among men and women in the U.S., with one person dying every 34 seconds of cardiovascular disease (CVD), according to the American Heart Association (AHA). This equals 2,500 people every single day, and it means more Americans die each year from CVD than cancer and accidental deaths combined.

And as the World Health Organization (WHO) points out, more than 80 percent of cardiovascular deaths are caused by heart attacks and strokes, with one third of these deaths occurring prematurely in patients aged 70 years or younger. Therefore, recognizing the signs of a heart attack—especially those that are more subtle—is one of the best ways to prevent a sudden and life-threatening episode.

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Half of all Americans are at heightened risk of a heart attack.

According to the Centers for Disease Control and Prevention (CDC), roughly half of Americans are believed to be at heightened risk of a heart attack. That’s because “half of all Americans have at least one of the three key risk factors for heart disease: high blood pressure, high blood cholesterol, and smoking.”

Other factors may also compound this risk: The presence of other underlying health conditions, certain lifestyle factors, advanced age, and a family history of heart problems are all associated with higher rates of heart attack.

“Some risk factors cannot be controlled, such as your age or family history. But you can take steps to lower your risk by changing the factors you can control,” says the CDC. These include quitting smoking, eating a healthy diet, maintaining a healthy weight, and treating underlying health conditions.

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This is the number one heart attack symptom people ignore.

Earlier this month, researchers at the University of Texas at Arlington published a paper titled “Heart attacks don’t follow a Hollywood script.”

“Many patients don’t experience the dramatic, big-screen version of a heart attack,” explains a press release. “Instead, symptoms can be complex and even mild.”

Basically, the researchers want the public to understand that cardiac episodes aren’t necessarily accompanied by intense, stabbing chest pains and a person collapsing.

“We often tell people chest pain is a symptom of a heart attack, but what we don’t tell them is what they might actually feel,” Ann Eckhardt, a nursing professor and researcher at The University of Texas at Arlington, explained. “For a lot of people, it’s not pain in the traditional sense. It’s more discomfort, pressure, tightness. They just don’t feel quite right, but they can’t really put their finger on it.”

In speaking with Best Life, Richard Wright, MD, a cardiologist at Providence Saint John’s Health Center in Santa Monica, California, says he completely agrees with this sentiment.

“Although it is possible to have severe chest pain during heart injury, most of the time the signs and symptoms are more subtle,” Wright notes. “Usually, people describe a feeling of oppressive discomfort and a heavy feeling that they don’t call ‘pain,’ most often located in the center of the chest.”

Some patients may describe this sensation as one of pressure, squeezing, or fullness, the CDC notes.

Wright adds that this discomfort may also present “in other areas of the body above the waist, including the left side of the chest, the neck and throat, the lower jaw, either shoulder, and/or the upper arms (most commonly the left arm).”

This feeling can last for several minutes uninterrupted, or stop and start.

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Be aware of these additional symptoms of a heart attack.

Wright adds that several other heart attack symptoms are similarly nonspecific and therefore easy to overlook. These include “a cold sweat, nausea, indigestion, heartburn, belching, ‘feeling poorly,’ and/or shortness of breath.”

The cardiologist notes that these types of symptoms “are far more common in older people and particularly in older women, as they typically don’t have heart attacks until 10 years after most men have heart attacks.

“Thus, although it is said that women feel heart attacks differently than do men, most of the time this is related to the fact that they are older at the time of their event,” he explains. “It is commonplace that older people fail to appreciate that their symptoms are related to an ongoing heart attack, and simply think that they are ‘ill’—perhaps related to a gastrointestinal problem.”

Don’t attempt to evaluate possible heart attack symptoms alone.

If you’re unsure whether you’re having a heart attack, do not ignore your concerns. It’s crucial to seek medical attention so a doctor can help assess your condition.

“Unfortunately, there is no simple way that someone can determine whether they themselves are having a heart attack if they have these signs or symptoms,” says Wright. “To distinguish whether these problems are related to a possible heart attack, an electrocardiogram, blood tests, or imaging studies are usually required—and typically these are only available in a medical environment.”

“If someone is concerned that they might be suffering from a heart attack, they need to immediately contact their medical professional, [go] to an emergency room, or call for paramedic assistance,” he urges.

Speak with your doctor for more information on possible heart attack symptoms, and call 911 immediately if you believe you may be experiencing heart attack symptoms.

This story has been updated to include additional entries, fact-checking, and copy-editing.

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