(WISH) — It’s a silent killer that can strike older and younger people.

Every 40 seconds in the United States, someone has a stroke, the U.S. Centers for Disease Control and Prevention says. But. not all strokes happen to older people. Up to 15% of them happen to people younger than 45.

Some people are born with arteriovenous malformations, also known as AVMs, and, once it ruptures in the brain, the effects can be life-altering and even fatal.

Meet Krysta Owings. “I started horseback riding when I was about 7 years old.”

Owings was 25, living her dream of working full-time in an equestrian barn until one morning.

“Woke up and started having, you know, some blurry vision, little bit of balance issues.”

In the emergency room, doctors diagnosed her with a ruptured AVM in her frontal lobe.

Dr. Gregory Zipfel, chief of the neurosurgery department at Washington University in St. Louis, said, “It’s a tangle of blood vessels that you’re born with. Most people have it for many, many years, often for a few decades, before they find out about it.”

Zipfel says AVMs are rare, and symptoms can be stroke-like. Other AVMs can can cause seizures. Some never cause any problems and are found during routine scans.

“We want to get it treated, and treated pretty quickly so it can’t rupture again.”

The doctor says 10% of patients who have AVM ruptures will die. Of those who survive, up to 30% will have long-term neurological problems due to where in the brain the rupture happened.

The doctor removed part of Owings’ skull and used a high-powered microscope. He sealed off the AVM with special clips and then remove it from the surrounding brain tissue.

Immediately after surgery, Owings still suffered the same symptoms. “I couldn’t use anything on my left side of my body. I couldn’t walk, I couldn’t tell time.”

But, that did change After three months, Owings was ready to get back on a horse and knew her buddy Swiper wouldn’t let her down. “He’ll just take care of you. He’s very intuitive, you know. He’ll listen to you.”

This story was created from a script aired on WISH-TV. Health Spotlight is presented by Community Health Network.