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Background: Tissue Doppler imaging (TDI), a non-invasive echocardiography technique, permits quantitative analysis of the regional distribution pattern of myocardial velocities. During normal childhood development, regional function changes markedly, including an increasing predominance of longitudinal velocities. This study analyzed the impact of heart transplantation on ventricular mechanics in growing children. Methods: TDI was performed in 30 pediatric heart transplant recipients (7.1 ± 6.2 years) and 32 age-matched healthy children (6.8 ± 5.4 years). Patients had no rejection history and were 3.1 years (median) post-transplant. Color TDI images from apical and parasternal views were stored as echocardiographic raw data. Off-line analysis was used to measure peak systolic and diastolic myocardial velocities in 6 basal cardiac segments for longitudinal (anterior, inferior, lateral, septal, right ventricle) and radial velocities (posterior). Isovolumic acceleration, a load-insensitive function marker, was determined as slope of the upstroke of the isovolumic contraction wave. Multiple regression modeling was used for statistics. Results: Systolic myocardial velocities still increased with age after transplantation, but the velocity distribution pattern was changed. In transplanted hearts, left ventricular longitudinal velocities were lower and radial velocities were higher than in the controls, but isovolumic acceleration was similar. In the right ventricle, longitudinal velocities and isovolumic acceleration were significantly decreased after transplantation. Wall motion abnormalities were present in 50% of patients. Conclusions: Regional wall motion analysis shows significant alterations of the fundamental biomechanical pump function of the left ventricle after heart transplantation in children, with a shift from longitudinal to radial fibers and depressed right ventricular wall motion. This may have important implications for the long-term graft function required in children. [Copyright &y& Elsevier]

This review details the indications for heart transplantation in children. Contraindications have evolved from absolute to relative. Controversial issues remain and this paper represents a consensus of more than a dozen centers that have programs that remain active performing pediatric heart transplants. [ABSTRACT FROM AUTHOR]

Objectives: We sought to analyze the indications and outcome of extracorporeal membrane oxygenation (ECMO) for early primary graft failure and determine its impact on long-term graft function and rejection risk. Background: Early post-operative graft failure requiring ECMO can complicate heart transplantation. Methods: A retrospective review of all children requiring ECMO in the early period after transplantation from 1990 to 2007 was undertaken. Results: Twenty-eight (9%) of 310 children who underwent transplantation for cardiomyopathy (n = 5) or congenital heart disease (n = 23) required ECMO support. The total ischemic time was significantly longer for ECMO-rescued recipients compared with our overall transplantation population (276 ± 86 min vs. 242 ± 70 min, p < 0.01). The indication for transplantation, for ECMO support, and the timing of cannulation had no impact on survival. Hyperacute rejection was uncommon. Fifteen children were successfully weaned off ECMO and discharged alive (54%). Mean duration of ECMO was 2.8 days for survivors (median 3 days) compared with 4.8 days for nonsurvivors (median 5 days). There was 100% 3-year survival in the ECMO survivor group, with 13 patients (46%) currently alive at a mean follow-up of 8.1 ± 3.8 years. The graft function was preserved (shortening fraction 36 ± 7%), despite an increased number of early rejection episodes (1.7 ± 1.6 vs. 0.7 ± 1.3, overall transplant population, p < 0.05) and hemodynamically comprising rejection episodes (1.3 ± 1.9 vs. 0.7 ± 1.3, overall transplant population, p < 0.05). Conclusions: Overall survival was 54%, with all patients surviving to at least 3 years after undergoing transplantation. None of the children requiring >4 days of ECMO support survived. Despite an increased number of early and hemodynamically compromising rejections, the long-term graft function is similar to our overall transplantation population. [Copyright &y& Elsevier]