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Excellent results are expected for children undergoing HTx with comparable results among diagnostic groups. Pretransplant mechanical circulatory support and posttransplant mechanical circulatory support are risk factors for decreased survival. Survival after transplantation for HLHS or HLHS-related malformation is better with primary HTx in comparison to HTx after prior cardiac surgery.

Highly sensitised children in need of cardiac transplantation have overall poor outcomes because of increased risk for dysfunction of the cardiac allograft, acute cellular and antibody-mediated rejection, and vasculopathy of the cardiac allograft. Cardiopulmonary bypass and the frequent use of blood products in the operating room and cardiac intensive care unit, as well as the frequent use of homografts, have predisposed potential recipients of transplants to allosensitisation. The expansion in the use of ventricular assist devices and extracorporeal membrane oxygenation has also contributed to increasing rates of allosensitisation in candidates for cardiac transplantation. Antibodies to Human Leukocyte Antigen can be detected before transplantation using several different techniques, the most common being the "complement-dependent lymphocytotoxicity assays". "Solid-phase assays", particularly the "Luminex® single antigen bead method", offer improved specificity and more detailed information regarding specificities of antibodies, leading to improved matching of donors with recipients. Allosensitisation prolongs the time on the waiting list for potential recipients of transplantation and increases the risk of complications and death after transplantation. Aggressive reduction of antibodies to Human Leukocyte Antigen in these high-risk patients is therefore of vital importance for long-term survival of the patient and cardiac allograft. Strategies to decrease Panel Reactive Antibody or percent reactive antibody before transplantation include plasmapheresis, intravenous administration of immunoglobulin, and specific treatment to reduce B-cells, particularly Rituximab. These strategies have resulted in varying degrees of success. Antibody-mediated rejection and cardiac allograft vasculopathy are two of the most important complications of transplantation in patients with high Panel Reactive Antibody. The treatment of antibody-mediated rejection in recipients of cardiac transplants is largely empirical and includes the use of high-dose corticosteroids, plasmapheresis, intravenous administration of immunoglobulins, anti-thymocyte globulin, and Rituximab. Cardiac allograft vasculopathy is believed to be secondary to chronic complement-mediated endothelial injury and chronic vascular rejection. The use of proliferation signal inhibitors, such as sirolimus and everolimus, has been shown to delay the progression of cardiac allograft vasculopathy. In some non-sensitised recipients of cardiac transplants, the de novo formation of antibodies to Human Leukocyte Antigen after transplantation may increase the likelihood of adverse clinical outcomes. The use of serial testing for donor-specific antibodies after cardiac transplantation may be advisable in patients with frequent episodes of rejection and patients with history of sensitisation. Allosensitisation before transplantation can negatively influence outcomes after transplantation. A high incidence of antibody-mediated rejection and graft vasculopathy can result in graft fai...

There are only a few reports of successful use of mammalian target of rapamycin (mTORI) as primary immunosuppression in pediatric heart transplantation. Compared to calcineurin inhibitors, mTORI have less side effects, especially nephrotoxicity, infections, and malignancies. A retrospective study was conducted at our institution of all 170 heart transplants from 1995 to 2015. Nineteen patients were switched from tacrolimus (n=15) or cyclosporin (n=4) to everolimus (n=4) or sirolimus (n=15) due to nephrotoxicity (n=5), malignancy (n=8), EBV viremia/reactive plasmacytic changes (n=5), and immune hemolytic anemia (n=1). We monitored for rejection, infection, BUN, creatinine, hyperlipidemia, EBV and CMV copies, CBC, cardiac allograft vasculopathy (CAV), and death. Target trough levels of sirolimus and everolimus were 4-10. Four treatment failures included debilitating rash, bone marrow suppression, recurrent rejection, and renal transplantation. There were no deaths. One patient had recurrent rejection episodes, and tacrolimus was reinitiated. One patient with preexisting CAV underwent heart retransplantation. One patient, who was treated for PTLD, transformed to CD30+ Hodgkins disease, and was treated with brentuximab. There were three acute rejection episodes. Median creatinine preswitch was higher 0.82 than postswitch 0.78 (P=.016). Median eGFR was lower preswitch, 75.6, than postswitch, 91.2 (P=.0004). These results indicate that conversion to mTORI as primary immunosuppression may be safely accomplished in some pediatric heart transplant patients.