The heart transplant that saved Brian Troy was made possible by a fellow Marine.

Troy, 43, of Rockford, served as a Marine in the 1980s. He was dying of an inherited heart condition in 2006 when he received a new heart in a transplant. The donor was 23. Troy didn't know much more than that.

Then Troy saw headlines about the murder of a 23-year-old Marine. He read about how Ricky Martinez survived two tours in Iraq, but he was shot to death in Chicago in a case of mistaken identity. The gunman thought a passenger in Martinez' car was a rival gang member, prosecutors said.

That was enough for Troy to guess his donor's identity. He then sent a thank-you letter to the family through an organ donor network. The first letter went unanswered, but a second, sent more than a year later, received a reply.

And just last month, Martinez' family and Troy met. His mother, Adalilia Cruz, placed her hand on Troy's chest to feel the heart beating.

"It shows you what kind of a person my son was," she said. "Even after his life was gone, he kept helping."

Troy agrees.

"Not only did I get a heart, but I got a very honorable heart," he said.

Nearly 98,000 people are waiting for transplant of a vital organ, according to the United Network for Organ Sharing. Troy works to encourage organ donation, organizing events and passing out fliers.

Illinois residents can register as organ donors at www.lifegoeson.com or by visiting any Secretary of State facility.