Longitudinal Assessment of Cardiovascular Exercise Performance After Pediatric Heart Transplantation

Diastolic Dysfunction of the Cardiac Allograft and Maximal Exercise Capacity

“…37 In pediatric HTx, exercise performance remains impaired and, despite an initial improvement, declines over time, probably due to increasing diastolic dysfunction independent of donor graft age. 38 In fact, this study has identified diastolic dysfunction as another relevant determinant of maximal exercise capacity in univariate and multivariate analyses. Univariate analysis showed significant correlations between several parameters of diastolic function and maximal exercise capacity, the strongest being the velocity of the early apical movement of the mitral annulus (Ea), and the ratio of the early to the late apical velocity of the apical movement of the mitral annulus (Ea/Aa).…”

Exercise Capacity Improves With Time in Pediatric Heart Transplant Recipients

“…PPVO 2 max increased with time in the earlier posttransplant period (Figure 3), which differs markedly from the available data in adult recipients 8,21 as well as the previous pediatric data. 9,18 Our cohort is more representative of the entire pediatric age range and a wide range of times post-transplant with serial data available.…”

“…9 Conversely, Davis et al found that exercise capacity decreases over time after an initial improvement post-transplantation. 18 Exercise capacity is better in children transplanted at a younger age, specifically infant transplant recipients. Abarbanell et al 1 demonstrated exercise capacity in infant recipients in the low normal range (VO 2 max of 32.3 Ϯ 5.6 ml/kg/min), which was higher than findings from older children and adolescents.…”

“…9 A recent longitudinal assessment demonstrated declining exercise capacity over time despite an initial improvement after HTx. 18 The primary purpose of this study was to profile the exercise capacity of pediatric HTx recipients over time and to look at factors associated with exercise capacity in addition to the potential for rehabilitation. Determination of a potential prognostic utility for serial exercise testing was also pursued.…”

Longitudinal Changes in Heart Rate Recovery After Maximal Exercise in Pediatric Heart Transplant Recipients: Evidence of Autonomic Re-innervation?

“…27,28 This is in part due to a limited ability of these subjects to increase HR with exercise. [27][28][29][30][31] Sympathetic re-innervation in adult heart transplant recipients is associated with not only higher peak HR during exercise but also with improved regional left ventricular function during exercise in innervated myocardial regions. 9,19 Although myocardial scintigraphic studies to study re-innervation have not been performed in pediatric heart transplant recipients, other previously published work indirectly supports this phenomenon.…”