Since the first successful surgery in 1967, researchers have worked tirelessly to perfect the process behind heart transplants. While there is still more work to be done, these procedures have given years back to the people who need them.
However, the number of people on the transplant list vastly outnumbers the amount of available organs. Medical professionals have high standards for the hearts that they accept, but a new study shows that some of the organs they reject aren’t necessarily unusable.
A new study shows that the blood tests that determine the usability of hearts may not be a good predictor of whether or not the transplant will succeed or fail. Specifically, the researchers say that rejecting hearts based on the levels of troponin I – which is currently common practice – is unnecessary.
Warning flag?
Troponin I is a protein found in heart muscle which finds its way into the bloodstream after the heart sustains some kind of damage. This could include damage done by heart disease or from an event like a heart attack. Currently, if medical professionals find high levels of the protein in the blood stream of a donor, then their heart is no longer considered viable for transplantation.
“If the heart looks okay but troponin I is elevated, many centers will reject the organ out of concern that this marker indicates dysfunction of the heart that will become evident after the stress of the transplant process,” explains Dr. Snehal R. Patel, senior author of the study and assistant professor of medicine at the Montefiore Medical Center at Albert Einstein College of Medicine.
To find out if high levels of the protein truly make a difference, Patel and his team conducted a study that analyzed the outcomes of nearly 11,000 heart transplants. Within this sample, they found that high levels of troponin I had no bearing on whether death occurred within the first year after surgery.
In fact, high levels of the protein made no significant difference in survivability rates over the first 30 days, year, three years, or five years after the transplant took place. There was also no association with complications like graft failure within the first 30 days or the proportion of people who developed allograft vasculopathy, a rapid form of heart disease.
Increasing heart availability
The researchers hope that their findings will help increase the number of hearts available for transplant so that people who need them have a greater chance of survival.
“Heart transplantation is an incredible therapy for patients with end-stage heart failure, but there are only 2,000 – 2,400 transplants each year. A lot of focus has been on finding ways to sign up more people as organ donors, but there is a also a problem in that only an average of one in three donor hearts are placed,” said Patel.
“Our research shows that transplant centers should not exclude donor hearts based solely on elevated troponin I if the organ is otherwise suitable. At our institution it has already changed how we evaluate donors, and I think this data will lead to changes nationwide,” he added.
The full study has been published in the journal Circulation: Heart Failure.