William F. Parker
Transplant center was associated with survival benefit of heart transplant recipients, according to findings published in JAMA.
Researchers found that high survival benefit transplant centers performed heart transplants for more patients with lower estimated expected waiting list survival without transplant compared with low survival benefit centers (29% vs. 39%; survival difference = 10 percentage points; 95% CI, –12 to –8.1). However, adjusted 5-year survival after transplant was not significantly different between high and low survival benefit centers (77.6% vs. 77.1%, respectively; survival difference = 0.5 percentage points; 95% CI, –1.3 to 2.3).
Researchers observed that for every 10% decrease in estimated transplant candidate waiting list survival, there was an increase of 6.2% in the 5-year survival benefit associated with heart transplant (95% CI, 5.2-7.3), according to the study.
“Hearts are scarce and, unfortunately, hundreds of patients die on the waitlist each year,” William F. Parker, MD, MS, instructor of pulmonary and critical care medicine at the University of Chicago, told Healio. “Federal regulations state that the Organ Procurement and Transplant Network (OPTN) should design allocation systems to give organs to the sickest candidates, with the goal of saving as many lives as possible. In heart transplantation, priority for transplant is determined by treatment intensity, with candidates receiving more intense treatment assumed to be sicker. However, treatment decisions are subjective and vary substantially between centers, as shown by previous work done by our group (Parker WF, et al. J Am Coll Cardiol. 2018;doi:10.1016/j.jacc.2018.02.030). This suggested to us that the therapy-based system might not effectively identify and prioritize the sickest candidates.”
In other findings, 5-year survival was 77% among patients who received transplant (interquartile range, 74-80) and 33% among patients who did not (interquartile range, 17-51).
“Our paper quantified the national variation in the ‘survival benefit’ of each heart transplant between transplant centers, which is how much patient survival was improved by receiving a heart transplant,” Parker told Healio in an interview. “While all centers achieve about the same ‘posttransplant’ survival (survival following transplant), certain centers are transplanting much sicker candidates than others. These ‘high benefit’ centers are effectively saving more lives with the scarce resource than the low benefit centers. In an ideal allocation system, there would be very little variation in survival benefit between centers.”
In this observational study, researchers aimed to identify a significant association between transplant center and survival benefit in the U.S. heart allocation system by assessing 29,199 patients (mean age, 52 years; 26% women; 67% white; 29% with diabetes) on the transplant waiting list. According to the study, survival benefit of transplant was defined by the difference in survival after transplant and waiting list survival without transplant at 5 years.
“In light of our previous work quantifying the variation in treatment practices between centers, our results weren’t too surprising,” Parker said in an interview. “We aren’t optimistic that the new six-tier system will improve the system much and believe that a heart allocation system based on an objective score (analogous to the model for end-stage liver disease for liver transplant) is needed.”
“Evaluating centers based on their use of potential organs, in addition to their survival benefit, would promote higher transplant rates,” Alexander T. Sandhu, MD, MS, cardiology fellow and health services researcher in the division of cardiovascular medicine at Stanford University, and colleagues wrote in a related editorial. “Moreover, large gaps in access to transplant centers and wait-listing persist across geographic and socioeconomic divisions. These disparities potentially affect patients who would have a large benefit with transplant. Suboptimal use of organs and barriers to patient access continue to limit the potential benefit of transplant on heart failure outcomes nationally.” – by Scott Buzby
Disclosures: Parker and Sandhu report no relevant financial disclosures. Please see the study and editorial for all other authors’ relevant financial disclosures.