Normalization of hemodynamics is delayed in patients with a single ventricle after pediatric heart transplantation

Objectives: The time course for hemodynamic normalization after pediatric heart transplantation has not been well characterized. We hypothesized that patients with a single ventricle would normalize later than those with dilated cardiomyopathy. Establishing the expected course based on the underlying pathophysiology will allow identification of patients who are outliers, requiring further investigation. Methods: We performed a retrospective review of patients with dilated cardiomyopathy, Glenn, and Fontan who underwent heart transplantation from January 2007 to December 31, 2017, and had 6-month and 1-year catheterization data. Hemodynamic data were examined for sustained normalization of pressures. Myocardial biopsies were reviewed for clinically significant rejection within the first year. Results: Ninety-four patients comprised the cohort (47 dilated cardiomyopathy, 18 Glenn, 29 Fontan) with a median age of 6.8 (12) years. Patients with dilated cardiomyopathy were more likely to normalize hemodynamics by 6 months (85% vs 28% Fontan, 44% Glenn, P < .05), and 96% of patients with dilated cardiomyopathy had normalized hemodynamics by 1 year (vs 62% Fontan, 78% Glenn, P < .001). The pulmonary capillary wedge pressure at 6 months was higher in patients who underwent the Fontan and Glenn (median 12.8 [8.8] mm Hg and 11.2 [5.9] mm Hg, respectively) compared with patients with dilated cardiomyopathy (7.0 [3.3] mm Hg, P < .001). Patients with dilated cardiomyopathy demonstrated normalized hemodynamics earlier (121 ± 72 days) than patients who underwent the Fontan (329 ± 62 days) and Glenn (233 ± 11 days, P < .001). Eighteen patients (19%) experienced significant rejection, which was not increased in patients with delayed hemodynamic normalization. The 6-month pulmonary capillary wedge pressure was associated with delayed normalization (hazard ratio, 1.36; 95% confidence interval, 1.16-1.60; P < .001). Conclusions: Patients with a single ventricle demonstrated delayed hemodynamic normalization compared with dilated cardiomyopathy heart transplant recipients, without affecting survival or need for retransplantation.