Lester Holt

Doctors managed to keep Autumn alive for two full days.

At some point, Sharon could tell that Autumn's grieving husband had run out of hope.

But in the ER suite, everyone knew it was.

Autumn's little girl was brought to her bedside.

On the third day after she'd been wheeled into the ER, Autumn's exhausted colleagues pronounced her dead and turned off the machines keeping her alive.

Auden's husband and family now had funeral plans to make and even darker days to get through.

But one person wasn't done with the mysterious case of Auden Klein.

His work was just getting started.

Dr. Todd Lukasiewicz, associate medical examiner for Allegheny County, performed the autopsy on Auden.

It was regarded as a sudden, unexpected death.

which meant the county needed to figure out why this otherwise healthy woman was dead.

There was no reason to suspect fertility hormones, vitamins or supplements like creatine could have led to her collapse.

Her brain showed no signs of a stroke, though an examination of the heart did reveal an abnormally shaped heart valve.

It's a congenital anomaly found in approximately 2% of the population.

Does it lead to early death?

Not in your 40s.

You need to be symptomatic.

At the conclusion of Autumn Klein's autopsy, the medical examiner was perplexed as to what killed this woman.

I'm not seeing anything.

I'm seeing a healthy white female that for all intents and purposes should be alive.