INVITED COMMENTARY

Abstract

More than 5,000 pediatric heart transplants have been performed worldwide. Advances in perioperative care, surgical techniques, and immunosuppressive and surveillance protocols have contributed to improved early survival of children transplanted in the recent era. In this report on pediatric transplantation the population is heterogeneous, the volume is small, and the mean follow-up is only 5.2 ± 3.6 years; nevertheless, the authors should be commended for their remarkable overall results. Survival in the Loma Linda pediatric transplant experience with more than 400 recipients (75% with complex congenital heart disease and 24% with cardiomyopathy) at 1-, 5-, and 10-year is 85%, 75%, and 66%, respectively. However, the 100 children transplanted as neonates have a significantly better 10-year survival compared with the other pediatric groups: 75% versus 64%.Primary graft failure is a disappointing development after transplantation, and its etiology is certainly multifactorial. Although this complication is part of every transplant center experience, the high incidence (12.7%) of severe right ventricular failure in this report is somewhat puzzling. To their credit, the transplant team changed their protocol after 1995, resulting in better early perioperative results. They avoided grafts with prolonged ischemic time (≥4 hours), rejected donor-recipient body surface mismatches, and used nitric oxide in 44% of their transplant procedures. In the absence of fixed pulmonary hypertension or high pulmonary vascular resistance index, acute graft dysfunction may be a function of graft preservation and procurement methods, intraoperative protection, implantation techniques, and management of graft reperfusion. In our series, neither prolonged graft ischemic time (range, 49 to 608 minutes) nor donor-recipient size mismatch (range, 0.59 to 4.65) had any adverse effect on early or long-term outcome of recipients with congential heart disease. Excessive transfusion of blood products is known to contribute to graft right ventricular dysfunction. Modification of surgical technique and the selective use of certain pharmacologic hemostatic agents can keep the incidence of postoperative bleeding to less than 8%, as compared with the 44% incidence of reexploration for bleeding reported in this series.The intermediate-term results of pediatric heart transplantation have improved considerably, but the durability of such therapy is threatened by the development of posttransplant graft vasculopathy, hypertension, renal insufficiency, malignancies, delayed rejection, and infection. These morbidities, along with compliance and psychosocial issues during adolescence, continue to challenge the commitment of transplant teams keen on enhancing the quality of life and achieving long-term survival for pediatric heart transplant recipients. More than 5,000 pediatric heart transplants have been performed worldwide. Advances in perioperative care, surgical techniques, and immunosuppressive and surveillance protocols have contributed to improved early survival of children transplanted in the recent era. In this report on pediatric transplantation the population is heterogeneous, the volume is small, and the mean follow-up is only 5.2 ± 3.6 years; nevertheless, the authors should be commended for their remarkable overall results. Survival in the Loma Linda pediatric transplant experience with more than 400 recipients (75% with complex congenital heart disease and 24% with cardiomyopathy) at 1-, 5-, and 10-year is 85%, 75%, and 66%, respectively. However, the 100 children transplanted as neonates have a significantly better 10-year survival compared with the other pediatric groups: 75% versus 64%. Primary graft failure is a disappointing development after transplantation, and its etiology is certainly multifactorial. Although this complication is part of every transplant center experience, the high incidence (12.7%) of severe right ventricular failure in this report is somewhat puzzling. To their credit, the transplant team changed their protocol after 1995, resulting in better early perioperative results. They avoided grafts with prolonged ischemic time (≥4 hours), rejected donor-recipient body surface mismatches, and used nitric oxide in 44% of their transplant procedures. In the absence of fixed pulmonary hypertension or high pulmonary vascular resistance index, acute graft dysfunction may be a function of graft preservation and procurement methods, intraoperative protection, implantation techniques, and management of graft reperfusion. In our series, neither prolonged graft ischemic time (range, 49 to 608 minutes) nor donor-recipient size mismatch (range, 0.59 to 4.65) had any adverse effect on early or long-term outcome of recipients with congential heart disease. Excessive transfusion of blood products is known to contribute to graft right ventricular dysfunction. Modification of surgical technique and the selective use of certain pharmacologic hemostatic agents can keep the incidence of postoperative bleeding to less than 8%, as compared with the 44% incidence of reexploration for bleeding reported in this series. The intermediate-term results of pediatric heart transplantation have improved considerably, but the durability of such therapy is threatened by the development of posttransplant graft vasculopathy, hypertension, renal insufficiency, malignancies, delayed rejection, and infection. These morbidities, along with compliance and psychosocial issues during adolescence, continue to challenge the commitment of transplant teams keen on enhancing the quality of life and achieving long-term survival for pediatric heart transplant recipients.