Limitations
This study was prone to limitations. First, this was a retrospective and
non-randomized review of donor heart offers and acceptances. As such,
its study design may be subject to selection bias. It is possible that
some transplanting centers may receive disproportionately higher or
lower quality heart offers, which may affect center acceptance rates and
outcomes of this study. While there is no quantitative metric of overall
quality of a heart offer, we did attempt to eliminate donor offers that
were likely of poor quality as evidenced by receiving no acceptances of
any solid organs from that donor. Furthermore, on multivariable
analysis, we adjusted for possible confounding donor and recipient risk
factors that may influence posttransplant survival. It is possible that
additional unmeasured variables may have influenced these results.
Lastly, to prevent possible bias from including highly inexperienced
centers, we removed all centers that performed less than 10 transplants
within the 5-year study period.