Study finds large discrepancies in the severity of illness among patients when they receive heart transplants.
Hospitals left to their own discretion may not be picking the sickest patients for heart transplants, a new study shows.
University of Chicago-led researchers looked at more than 29,000 adults on the national heart transplant registry from 2006 through 2015 and found large discrepancies in the severity of illness among patients when they receive heart transplants.
The study was published this week in the Journal of the American Medical Association.
"These are all patients with end-stage heart failure who have exhausted most of their options. They all need transplants, but there aren't enough donor hearts to go around," said study led author William Parker, MD, a pulmonologist and ICU physician at the University of Chicago.
"But the system is set up such that transplant centers have a lot of control over determining which patients receive top priority for transplant, which makes it a very nuanced problem," he said.
Over the decade-long study period, the average "survival benefit" – which is scored as the percentage increase in chances of survival – for heart transplants ranged from 30% at low survival benefit hospitals to 55% at high survival benefit centers. One-quarter of the 113 transplant centers studied were low benefit centers, and one quarter were high benefit centers, the study found.
For heart transplant recipients, the overall survival rate was about 77% across all centers.
Parker said the findings suggest that the high survival hospitals prioritize sicker patients, giving hearts to patients with lower chances of survival without a transplant and boosting their survival benefit.
Conversely, the low survival hospitals are "playing it safe" and giving organs to less critically ill patients who receive a smaller benefit from the transplant.
"I don't think anybody's acting in bad faith. They're doing what they have to do to get their patients taken care of," Parker said. "But we found that centers that take risks on sicker candidates still manage to achieve good post-transplant outcomes, which leads to more lives saved."
Parker sees a connection between his study results, and federal regulations that until 2018 required hospitals to rank heart transplant candidates on a three-tier scale.
The rankings relied on the intensity of treatment they receive. Patients on high-dose inotropic medications, or those receiving mechanical heart support devices like intra-aortic balloon pumps, were deemed the highest priority.
In a study last year in the Journal of the American College of Cardiology, Parker and his colleagues showed that the rules incentivized hospitals to overtreat patients with more intensive therapies to boost their status for transplant.
"When I started to dig more into the data, it turned out that most patients on the list, over time, had become the top priority tier," he said. "Centers that had lots of nearby competitors were much more likely to overtreat their candidates to get them into the top priority tier."
Parker says his new study suggests that some hospitals during the study period cherry-picked transplant recipients, overtreated them to raise their profile on waiting lists, with the anticipation of an easier post-transplant recovery with higher survivability rates.
The Organ Procurement and Transplant Network in 2018 implemented a new six-tier model for assessing patients in need of a heart transplant.
In his new study, Parker re-coded transplant candidates according to the new six-tier system and found that – while providing more balance in the selection process – it still doesn't account for how hospitals will likely change their practices to adapt to the new system.
Parker said problem is stubborn because hospitals control which heart patients get transplants, relying on a system that matches treatments with severity of illness.
Other organ transplant programs rely on objective measures based on MELD lab tests, which remove much of the discretion in candidate selection that hospitals now have. Because of that, Parker does not anticipate big changes under the newer six-tier model.
"If the system was working perfectly, the variation among centers would be very small," Parker said. "But there are good reasons to believe that the new system won't actually allocate hearts to the sickest patients either because centers still would have a lot of influence on deciding the priority status of patients at their center and who actually gets transplanted."
“The system is set up such that transplant centers have a lot of control over determining which patients receive top priority for transplant, which makes it a very nuanced problem.”
William Parker, MD, University of Chicago.
John Commins is a content specialist and online news editor for HealthLeaders, a Simplify Compliance brand.
'High survival benefit' hospitals prioritize sicker patients, giving hearts to those with lower chances of survival, and boosting their survival benefit to a greater degree.
Conversely, some hospitals cherry-pick transplant recipients, overtreat them to raise their profile on waiting lists, and anticipate easier post-transplant recovery with higher survivability rates.