Jackie Ng-Osorio, 27, a runner since her cross-country and track days at Kamehameha Schools, had begun training seriously again hoping to break some personal records, when life suddenly threw her a curveball.

"It was June 29, the Mango Days 5K," she said. "I felt great that day and really enjoyed my race."

Little did she know that everything would change the next morning.

She went on an easy run with training partners Mina Casey-Pang and Kelli Lyau before reporting to her job as an education coordinator at Hawai'i Medical Service Association. She remembers waving goodbye to them, heading to her office and not feeling well. It was the same feeling she would get after a hard workout, but that morning's run was anything but that.

200 beats per minute

"I thought a cold shower would help and that's when I noticed I could see my heart beating through my chest," she said. After an hour, she called her physician when co-workers told her she looked pale. At the doctor's office, an ambulance was called when a nurse realized her heart was pumping at 200 beats per minute.

A four-day hospital stay followed with tests and an angioplasty. The initial diagnosis was tachycardia, an arrhythmia, or an abnormal heart rhythm. Electrical impulses traveling through her heart were taking a shortcut. She underwent an electrophysiology study with Dr. Edward Shen to determine the exact location in her heart that was producing the arrhythmia. The goal was to correct it using a procedure called catheter ablation, in which the path is burned to close the shortcut.

In most cases, the ablation solves the problem and the patient's heart rhythm returns to normal, but that wasn't the case with Ng-Osorio.

Six weeks later while bending down to pick up something, she had a recurrence of the rapid heartbeat. A second ablation was ordered. This time during the process, she experienced complete heart block where her heart stopped for about five minutes.

Eight days after that incident, she noticed her heart rate slowing. An EKG determined complete heart block, or that her atrium and ventricle were not communicating.

"At that point, my life changed when my doctor told me I needed a pacemaker," she said.

Ng-Osorio was in disbelief at first, but now accepts the fact that nothing could have been done to prevent it. "The arrhythmia could have been triggered at any point in my life," she said. "I could have been sedentary and it still could have happened."

Her state-of-the-art Medtronic Dual Lead Pacemaker was implanted through her left shoulder. The only physical evidence of her ordeal is a 1›-inch scar.

Two months after the procedure, she was determined to run again. With the approval of her doctor, and support from her family and husband, Kane Ng-Osorio, she laced up her running shoes.

"I had uncertainties about running, I was looking for excuses," she said. "So much had happened and I was scared. My first run was three-fourths of a mile. My legs wanted to go (faster) than my heart."

A new motivation

Kane, a competitive runner who once motivated his wife toward getting faster, says things have changed.

"Now I try to discourage her from getting caught up in the training for a personal record or the fast times she used to run. Instead, I want her to enjoy the run as a way of taking good care of her body and staying in shape, physically, mentally and spiritually."

Ng-Osorio is looking forward to the 8.15 mile Great Aloha Run as her "Post-Pacemaker Debut."

She'll be running with five good friends.

"I helped them train for the Honolulu Marathon this year — all first marathons — giving them inspiration and tips," she said. "All of them finished the race and never gave up."

Giving up is not a part of her vocabulary. Her goal is not to walk during the Great Aloha Run.

"It's OK if I can't run my best times anymore," Ng-Osorio said. "If I can just run, I'm a happier person. This year, no matter what my time is, I'll feel good."