A blood test that’s used to check the health of a donor heart may not accurately predict if a heart transplant will be successful, a new study finds.
Placing less emphasis on this blood test could increase the number of hearts available for end-stage heart failure, the researchers said.

“Heart transplantation is an incredible therapy for patients with end-stage heart failure, but there are only 2,000 to 2,400 transplants each year,” said senior study author Dr. Snehal Patel.

“A lot of focus has been on finding ways to sign up more people as organ donors, but there is also a problem in that only an average of one in three donor hearts are placed,” explained Patel. He is an assistant professor of medicine at Montefiore Medical Center and Albert Einstein College of Medicine in New York City.

The blood test in question checks levels of a protein called troponin I. This protein enters the bloodstream when a person suffers a heart attack or other heart muscle damage, the study authors said.

“If the heart looks OK 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. We looked at whether this is true,” Patel said.

For the study, the researchers looked at how well U.S. patients did after nearly 11,000 heart transplant surgeries. The patients were all 18 and older.

The investigators found no association between donor troponin I levels and the risk of death during the year following transplant.

In addition, donor troponin I levels had no significant effect on recipients’ survival at 30 days, one year, three years or five years, the findings showed. Troponin levels also didn’t seem to affect the risk of serious complications.

The study was published in the June 21 issue of Circulation: Heart Failure.

“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,” Patel said in a journal news release.