High school teacher Debra North constantly felt worn out in the days leading up to spring break.

Then one day during lunch, she felt numbness in her right arm and pressure on her chest. She was planning to finish the day, but school officials called an ambulance.

North soon learned her mitral valve was failing. She had surgery to repair it in June 2006.

The diagnosis took then-30-year-old North by surprise, despite having dealt with heart issues since birth, when she survived both a heart attack and stroke. She’d been diagnosed with mitral valve prolapse shortly after birth but had always been told she’d be well into her 60s before a repair or replacement of the heart valve would be needed.

North, who lives in Downey, California, didn’t realize her relentless fatigue was actually a sign that something was wrong with her heart valve.

“I just figured I was a stressed-out teacher who needed a break,” North said. “Actually, I had been tired for months.”

“Heart valve disease is relatively common, affecting an estimated 2.5 percent of U.S. adults, though it often goes undiagnosed because many people do not experience symptoms,” said Vuyisile T. Nkomo, M.D., director of the Valvular Heart Disease Clinic at the Mayo Clinic.

Chest tightness or pressure, like North experienced, is one symptom of heart valve disease. The most common symptoms include shortness of breath or feeling easily fatigued, which can be mistaken for other conditions.

“People think, ‘I’m getting old, or I’m out of shape,’” said Nkomo. “If you are more easily tired than your peers or having other issues, you need to ask your doctor if it could be valve-related.”

For those without a congenital condition like North, the risk of developing the condition increases with age, Nkomo said.

Valve repairs or replacements were once only possible through open-heart surgery. But some can now be done using a catheter through the groin or minimally invasive procedures — newer options that have caused doctors to be more aggressive in treating some patients, doing a valve repair or replacement earlier instead of waiting for the condition to become more severe, Nkomo said.

Heart valve disease worsens over time, although the progress can be so slow that it isn’t detected until the condition becomes severe. For example, a heart murmur that didn’t cause problems before can lead to serious heart valve disease later, Nkomo said.

“Just because you’ve had a murmur for a long time doesn’t mean it can’t cause issues later in life,” he said.

Increasing awareness about valve disease is important, Nkomo said, because “the symptoms often come on so slowly, patients adjust their routines gradually without realizing why,” he said. “Early detection is important, followed by surveillance and early treatment.”

Complications from North’s valve repair led to a valve replacement in June 2016. She again experienced similar symptoms to the ones she had a decade earlier, finding herself out of breath while teaching and going to bed as early as 7 p.m., even on weekends.

“This time I knew what to watch for, so I kept checking with my doctor to determine if it was time to do a replacement,” she said.

North, now 42, will this month have her second valve replacement. She is already in heart failure because her tissue valve is struggling, and will be replaced with a mechanical one.

North volunteers as an American Heart Association Heart Valve Ambassador and said the experience has shown her how crucial it is to pay attention to your body and any changes that can’t be explained.

“Take charge of your health,” she said. “Don’t just ignore it or convince yourself it’s nothing. Talk to your doctor.”

And if you feel your concerns aren’t being taken seriously, don’t be afraid to get another opinion or change doctors, North said.

“You need to feel comfortable expressing concerns and not feel like you are being treated like a hypochondriac,” she said. “You really have to be partners in your care and come up with a game plan together.”

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