Full Recovery of Right Ventricular Systolic Function in Children Undergoing Bilateral Lung Transplantation for Severe PAH

Background: We investigated whether RV function recovers in children with pulmonary arterial hypertension (PAH) and RV failure undergoing lung transplantation (LuTx). The major research questions were how completely and how quickly after LuTx, the detrimental ventricular-ventricular interaction and systolic RV function recover in children with PAH.

Method: Prospective observational study of 15 consecutive children (age range: 1.9–17.6 years) with severe PAH who underwent bilateral lung transplantation at Hannover Medical School between December 2013 and January 2021. We performed advanced echocardiography (Echo) and cardiac magnetic resonance imaging (MRI), followed by conventional and strain analysis, pre-, and approximately 6 weeks post-LuTx.

Results: All patients had PAH, that is, group 1 pulmonary hypertension: idiopathic (n = 6), heritable (n = 4), PAH-congenital heart disease (n = 2), and pulmonary venoocclusive disease/pulmonary capillary hemangiomatosis (PVOD/PCH; n = 3). Six weeks after LuTx, RV/LV endsystolic diameter ratio (Echo), RV volumes, and systolic RV function (RVEF 63 vs. 30%; p < 0.05) by MRI completely normalized, even in children with severe RV failure (RVEF < 40%). The echocardiographic end-systolic LV eccentricity index nearly normalized post LuTx (1.0 vs. 2.0, p < 0.0001) while RV hypertrophy regressed more slowly and was still evident. We found especially the end-systolic RV/LV ratios by Echo (RV/LV diameter; 0.6 vs. 2.6) or MRI (RV/LV volumes: 0.8 vs. 3.4 excellent diagnostic tools (p < 0.05); together with RVEF by MRI, these ratios were superior to tricuspid annular plane systolic excursion (TAPSE; p > 0.05) in assessing global systolic RV dysfunction. Moreover, children with severe PAH had reduced RV 2D longitudinal strain (Echo, MRI; p < 0.05) and decreased RV 2D radial and circumferential strain (MRI; p < 0.01), all of which greatly improved following LuTx. One-year survival after LuTx for PAH was 100% (15/15 patients alive; 1 retransplant 9 months after the initial LuTx because of acute fibrinous, organizing pneumonia consistent with cellular rejection).

Conclusion: We demonstrate full recovery of RV systolic function in children within 2 months after LuTx for severe PAH, independently of the patients’ age, weight, and hemodynamic compromise preceding the LuTx. Even in end-stage pediatric PAH with poor RV function and low cardiac output, LuTx should be preferred over heart–lung transplantation.

Publication History

Article published online:
12 February 2022