Mammalian Target of Rapamycin Inhibitors and Survival in Heart Transplant Recipients: Miracle or Mirage?

We read with great interest the recent paper by Asleh et al. [(1)][1], who reported prolonged survival with sirolimus versus a calcineurin inhibitor in a cohort of 402 heart transplant (HT) recipients. We were quite surprised by this finding, given that no randomized controlled trial of mammalian