It’s a typical feeling for people when they watch a scary movie, walk alone in the dark in an unfamiliar place or face a time crunch on an important exam: Their hearts race, jump, pound and skip.

But it’s a phenomenon also experienced by people who don’t have any unusual external stimuli.

At least 2.7 million people in the U.S. have a condition known as atrial fibrillation, which is characterized by abnormal heart rhythms. Indeed, as many as 20 percent of adults will have irregular heartbeats at some point in their lives, according to Richard Wright, a Santa Monica-based cardiologist.

“It’s a common way for the heart to misbehave,” he said.

Wright is trying to educate the public about the condition as part of Atrial Fibrillation Awareness Month, a campaign by the National Stroke Association and others to encourage senior citizens and other people to have their hearts checked.

In people with atrial fibrillation, the upper chambers of the heart can get out of sync with the lower chambers. That dynamic can lead to the formation of blood clots, which increases risks for stroke.

“The vast majority of strokes due to Afib are avoidable,” he said. “Sometimes patients don’t have symptoms, and some people don’t even know they have it. But hundreds of thousands of people have had a stroke that would’ve been preventable had they taken appropriate remedies.”

It’s an important cause for Wright, who has worked for 30 years at Providence Saint John’s Health Center and who currently serves as chairman of the locally based Pacific Heart Institute.

Wright grew up in the San Francisco Bay Area, later attending medical school at Harvard University and completing his residency and fellowship there.

He gravitated towards cardiology, he said, because it requires both long-term preventive care and acute treatment. He found it intellectually stimulating. He was also inspired by his mentor, Bernard Lown, a Lithuanian cardiologist who won a Nobel Peace Prize for his efforts to prevent nuclear war.

Wright eventually landed in Santa Monica, where he’s held a clinical practice for decades.

“It’s a great place with a great medical staff and excellent nursing personnel,” he said. “It’s the exemplar of what a terrific community hospital should be.”

Wright said he’s proud to work at a hospital that is known as a leader in the field for an alternative to blood thinners, which are commonly administered to AFib patients.

Medical professionals from other areas are scheduled to visit the local center in a few weeks to learn about the so-called Watchman, a fabric umbrella that Saint John’s doctors have been implanting in patients for 11 years. The device is helpful for elderly people who are more vulnerable to bleeding and for people who cannot take anticoagulants, he said.

Wright encourages senior citizens to have electrocardiograms taken to assess their heart health. AFib is easier to diagnose in people who regularly experience symptoms, but he said many patients monitor their hearts outside a doctor’s office to get more accurate portraits of their heart activity. He added that digital telemedicine tools “will revolutionize the field” because they can transmit information from wrist-worn devices to medical professionals’ databases.

Although age is the principal AFib predictor, Wright said, untreated high blood pressure, diabetes and obesity can also increase risks for the condition.

“Even if you live the life of Jesus,” he said, “it’s possible you can develop AFib just because you’re 85 years old.”