On Friday, an EMT in Detroit named Joseph Hardman was performing CPR on a heart attack victim in the back of an ambulance on the way to the hospital.

And in the middle of giving CPR, Joseph started having chest pains himself ... because it turned out HE was having a heart attack too.

But he still helped the other EMT make sure their patient made it to the hospital's cardiac unit, before taking care of himself.

Doctors immediately started treating Joseph when he came into the E.R.  It turns out he had a blockage in an artery referred to as the "widow maker"...because you hardly ever survive a blockage there.

Luckily, Joseph did survive it...simply because he showed up to the hospital so quickly.  And his doctor says he should be back at work in a few months.

And his patient also survived.  In fact, Joseph ended up three beds down from him after they were admitted.

Read more: Detroit Free Press