Last October, Susan Koeppen posted to her Twitter account that she'd just completed a one-mile training run: "Just 12 more to go. I'll finish half marathon if it kills me!"

It nearly did. But Monday evening, she co-anchored the KDKA 6 o'clock news, a improbable but happy ending to a two-month series of events that played out like a Lifetime movie.

The facts are these: On the morning of Nov. 20, Ms. Koeppen collapsed while running with friends in Shadyside.

She suffered cardiac arrest, and her heart had to be shocked back into action right there on the sidewalk. After three days in an intensive care ward, heavily sedated, she regained consciousness. Then she got better.

But the facts don't tell the full story: Ninety-five percent of all people who experience that sort of cardiac event outside of a health care setting die.

She is among the 5 percent who lived, mostly because of the almost unbelievable luck of being at the right place with the right people at the right time.

"It's almost miraculous, although I hate using that word because people use it so often," said Jim O'Toole, Ms. Koeppen's husband of 10 years. "It's like having the greatest Christmas gift ever, and getting it every single day."

Her friend Beth Sutton-Diegelman agreed: "It's one of those things that even though I want to cry about it, just the magnitude makes you grateful. It truly is a miracle."

Ms. Koeppen, 39, a mother of three young children, had always been active in sports and recently had taken up running races. She knew she had a fairly common condition known as mitral prolapse. This led to mitral regurgitation: blood in the left ventricle flows back into the left atrium because the mitral valve leaflet isn't closing properly.

"I was first diagnosed with mitral valve prolapse years ago, which is very common in women," she said. "A couple of years ago, I began having moderate regurgitation, so we've known about and followed it for years."

But the signs of trouble were there, she said: "Coughing, shortness of breath, tiredness, light-headedness. I had all of these, but if you're a working woman, you have these [anyway]. I would hear, 'You're just working too hard, it's stress, oh, you might have exercise-induced asthma.' "