Andersons pediatric cardiology 1788

FIG 67.24 Freedom from cardiac allograft vasculopathy (CAV) in children after heart transplantation stratified by age group (From the registry of the International Society of Heart and Lung Transplantation J Heart Lung Transplant 2016;35(10):1185–1195.) FIG 67.25 Kaplan-Meier survival following diagnosis of cardiac allograft vasculopathy (CAV) in children after heart transplantation stratified by age group (From the registry of the International Society of Heart and Lung Transplantation J Heart Lung Transplant 2016;35(10):1185–1195.) Because of the limitations of angiography, intravascular ultrasound has been proposed as a better means of identification and study of the progression of epicardial CAV The early enthusiasm has been tempered by technical issues, cost, and lack of meaningful endpoints for management and/or prognosis Its use is currently limited to older children owing to the size of the available catheters; most often it plays an ancillary role in decision making.75 The utility of MRI is being explored but has not yet reached the level of replacing angiography, either from an imaging perspective or, more recently, assessment of the microcirculation.76 Optical coherence tomography is used in a few centers as a supplementary tool, but it has not reached widespread application in the pediatric population.77 Lipid-lowering therapy, using statins, has been shown to play a role in the prevention of CAV In adults, pravastatin has been shown to reduce the incidence of acute rejection associated with hemodynamic compromise, to improve survival at 1 year, and to reduce the development of CAV.78 This was independent of the level of cholesterol, suggesting that the effect of statins extends beyond the manipulation of lipids Similar findings have been reported with simvastatin.79 There are limited data in children, with two studies showing a lower incidence of CAV during treatment with simvastatin or atorvastatin.80,81 A larger retrospective registry-based analysis showed no impact on outcomes.82 Nevertheless, statin use has been incorporated in most of maintenance therapies for pediatric heart transplant recipients Treatment of established CAV is challenging, especially in children There are only three reports of interventions in a small number of children, making definitive recommendations impossible.83–85 The majority of patients are not amenable to these techniques owing to the diffuse nature of the disease Ultimately patients with moderate to severe CAV and evidence of graft dysfunction may be candidates for retransplantation Retransplantation Retransplantation makes up a very small proportion of heart transplants in children annually and is more common in North America than the rest of the world (see Figs 67.4 to 67.8) Overall, numbers have decreased over the last decade, with less than 25 reported to the ISHLT registry in 2014 (Fig 67.26) There is ongoing controversy regarding the role of retransplantation, given the decreased long-term survival and an increase in transplant-related morbidities,86 especially in the context of organ donor shortages (Fig 67.27) Overall survival following retransplantation approaches that of primary transplantation when retransplantation occurs later than 1 year after primary transplantation (Fig 67.28) Retransplantation for early graft failure or acute rejection, the usual causes of death in the first year, carries a high mortality (Fig 67.29) For patients transplanted within 1 year of their primary transplant, the 1-year actuarial survival is 55%, compared with almost 90% for those retransplanted beyond 5 years after the primary transplant FIG 67.26 Retransplantation in children by year (From the registry of the International Society of Heart and Lung Transplantation J Heart Lung Transplant 2016;35(10):1185–1195.) ... A larger retrospective registry-based analysis showed no impact on outcomes.82 Nevertheless, statin use has been incorporated in most of maintenance therapies for pediatric heart transplant recipients Treatment of established CAV is challenging, especially in children