"We have to be stewards of a very valuable resource. We want hearts to go to people who we think will benefit the most from them," said Dr. David Taylor, immediate past president of the International Society for Heart and Lung Transplantation.
These decisions are, to some extent, subjective, as doctors sometimes disagree with each other about who should get an organ. Over the years, medical ethicists and patient advocates have accused transplant physicians of discriminating against one group in particular: the disabled.
"We absolutely know this happens. It's a huge problem," said David Magnus, director of the Center for Biomedical Ethics at Stanford University. "It's real people sitting in a room making these tough decisions, and it's not surprising their own prejudices and biases influence them."
He points to the case of Amelia Rivera, a New Jersey girl with disabilities who was denied a kidney transplant last year, and to a survey he conducted in 2008 showing that more than four out of 10 pediatric transplant centers say they always or usually consider a child's neurodevelopmental delays when making a transplant decision, even though studies have found children with these delays fare just as well medically after a transplant as other children.
Ari Ne'eman, president of the Autistic Self Advocacy Network, agreed that doctors sometimes "blow smoke" at patients with disabilities.
"Doctors give faux medical reasons. On further scrutiny, they don't stand up," said Ne'eman, who wrote a policy brief on the issue. "When someone with a disability is looking for a transplant, discrimination is the norm."
Transplant doctors said they don't discriminate against people with disabilities, but that disabilities need to be considered when making transplant decisions.
For example, Taylor, a heart transplant cardiologist at the Cleveland Clinic, said physicians must weigh whether a patient -- any patient -- is willing and able to follow complicated post-transplant medication directions. If the patient doesn't follow doctors' orders, the body could reject the new organ.
"If I were to go in front of the transplant committee, they'd want to stop and see if I'm some pompous doctor who's not going to listen to instructions," he said. "That has to be taken into account."