When a 19-year-old collapsed on a stage where Robert Morris University students were rehearsing for a production of "Godspell," the frantic call went out:

"Does anyone know CPR?"

Answering the call for cardiopulmonary resuscitation were two performers inside the Pittsburgh Musical Theater studios on West Main Street in the West End.

What no one knew, at that point, was that Ryan Collins' heart had gone into ventricular fibrillation. That's a mostly fatal condition in which the heart's electrical activity becomes erratic, causing its lower chambers to contract in a rapid, unsynchronized way.

Unless medical help is provided immediately, sudden cardiac death occurs within minutes, according to a news release from Allegheny General Hospital. The survival rate for people who experience sudden cardiac arrest is less than 10 percent.

Mr. Collins, of Robinson, a freshman at Robert Morris University, beat the odds. He survived, with what medical personnel call "no neurological deficits."

His life was saved by a large cast of people who were all in the right place at the right time doing exactly the right thing.

The story of Mr. Collins' salvation and recovery ends at Allegheny General Hospital, where doctors, nurses and other personnel employed state-of-the-art treatment and surgery.

The story begins with the people who kept his heart, lungs and brain working prior to his arrival at the hospital on the North Side.

When Mr. Collins collapsed on Jan. 22, Leah Zahner, 23, did not see it because she was in another room, rehearsing her singing and acting role for a PMT production of "High School Musical." She heard the call for help, and didn't hesitate.

She had never met the actor whose unmoving body lay on the floor while Lisa Elliott, a PMT dancer and instructor, performed chest compressions. Ms. Zahner did mouth-to-mouth resuscitation, the second component of CPR.

All of that is "a complete blank," said Mr. Collins. "I do not recall a thing from that day. The first thing I remember, I woke up in the hospital and saw my parents."

He regained consciousness one week after his collapse, his parents told him.

The first responders on the scene at the theater were Michael Hill and Mary Kovac, from the city's Medic 3 paramedic crew. They used a defibrillator, but his erratic heart rhythm did not change. They started an IV line and administered "standard cardiac medications."

A second shock resulted in a weak carotid pulse that was soon lost. More medications were administered, along with a third shock that restored his pulse and got a better heart rhythm going.

Also assisting at the scene were paramedics Edward Carlino and Scott Lowman, of Rescue 2, and the crew of Engine 30, including Lt. John Gardner and firefighters Shaun Trosky, Jeffrey Wright and Tom Petronio.

When he arrived at AGH, Mr. Collins was placed in an induced hypothermic state -- his body temperature was lowered 8-10 degrees to protect his heart and brain from damage.

He also spent four days connected to a device that is similar

to a heart-lung machine, said Dr. David Dean, a thoracic and cardiovascular surgeon who is chief of the AGH Section of Transplantation and Mechanical Assistance Program.

The machine allowed his heart to heal and supported all of his major organs. It pumped blood, removed carbon dioxide and added oxygen.

Surgeons implanted a permanent defibrillator. If Mr. Collins goes into ventricular fibrillation again, it will deliver electrical shocks to get his heart back into a normal rhythm.

Mr. Collins was discharged Feb. 9, and after a week of rest, he returned to classes. He said his life is basically back to normal except that he was advised, not too much activity for a while.

He met his life savers Feb. 25 and said he appreciates everything everyone did for him; he was happy to have the chance to thank them in person.

"I had never met Leah before," Mr. Collins said.

Ms. Zahner first learned CPR when she took a baby-sitting course when "I was about 13. I've recertified several times and I'm so grateful I did."

Meeting Mr. Collins was a "very powerful" moment, Ms. Zahner said. "It was so great to see him up and walking and joking around."