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.