Outcomes after Early Initiation of mTOR-Inhibitors in Adult Cardiac Transplant Recipients.

Purpose The effect of mTOR-inhibitors initiated as maintenance immunosuppression early after cardiac transplant is not well-established. Current outcomes data are limited to small, single-center studies. Methods 22,173 adult cardiac transplant recipients from the United Network for Organ Sharing database between 2008 and 2018 were included in current study. Propensity-matching was carried out to match 184 patients started on proliferation signal inhibitor (PSI) maintainence therapy (sarolimus or everolimus) before discharge with 184 controls. Outcomes included mortality/graft failure, development of coronary artery disease, infection, and acute rejection. Results PSI and No PSI cohorts were well-matched with regards to age (40.4 vs. 50.6), gender (32% vs. 30% females), race (60% vs. 63% white), LVAD use (28% vs. 30%), UNOS status (54% vs 55% 1A), HF etiology (32% vs 31% ischemic), and other immunosuppressive medication use (all p=NS). Compared to controls, PSI group had significantly lower rates of coronary artery disease (17.8%, 95% CI 12.1%-24.4% versus 27.9%, 95% CI 20.9%-35.5; P= 0.04) (Figure). However, risk of hospitalization for rejection (36.1% vs. 23.7%, p=0.043) and hospitalization for infection (40.6% vs. 28.8%, p=0.011) at 5 years were significantly higher in the PSI group. Mortality and graft failure rates were comparable between PSI and No PSI groups. Conclusion mTOR-inhibitors initiated early as part of a maintenance immunosuppression regimen may reduce the long-term risk of developing coronary artery disease at the expense of higher risk of rejection and infection in adult cardiac transplant recipients. These findings suggest that switching to PSI at a later time point may be a more effective strategy in minimizing post-transplant complications compared to early initiation of PSI. [ABSTRACT FROM AUTHOR]