Impact of the operative technique on mid- and long-term results following paediatric heart transplantation.

AIMS: The aim of this study is to evaluate and compare the impact of the bicaval technique versus the biatrial technique (by Lower and Shumway) in paediatric heart transplant patients. Only a few studies investigate this matter regarding the long-term outcome after paediatric heart transplantation. We compared the two surgical methods regarding survival, the necessity of pacemaker implantation. METHODS AND RESULTS: All 134 patients (aged <18 years) - (group-1) biatrial (n = 84), versus (group-2) bicaval (n = 50), who underwent heart transplantation between October 1988 and December 2021, were analysed. Freedom from events were estimated using the Kaplan-Meier method. Potential differences were analysed using the log rank test and Cox proportional hazard models. Mean ± standard deviation: Bypass time (per minutes) was higher in the group 1 as compared with group 2 (P = 0.050). Survival was not significantly different (P = 0.604) in either groups. Eighteen patients required permanent pacemaker implantation in the group 1 and only one patient required it in the group 2 (P = 0.001). CONCLUSIONS: Paediatric heart transplantation using bicaval technique results similar long-term survival compared with the biatrial technique. The incidence of atrial rhythm disorders was significantly higher in the biatrial group, requiring a higher frequency of pacemaker implantation in this group. As a results, the bicaval technique has replaced the biatrial technique in our centre.

Evaluation of the diagnostic and prognostic potential of optical coherence tomography (OCT) of the pulmonary arteries during standardised right heart catheterisation in patients with pulmonary hypertension: a cross-sectional single-centre experience.

Background: Pulmonary hypertension (PH) is diagnosed based on an invasive evaluation of the mean pulmonary artery (PA) pressure. The morphological assessment of the pulmonary arteries was only recently not feasible. With the advent of optical coherence tomography (OCT)-imaging, an accessible tool allows to study PA morphology longitudinally. The primary hypothesis was that OCT distincts the PA structure of PH patients from control subjects. The secondary hypothesis was that PA wall thickness (WT) correlates with the progression of PH. Methods: This is a retrospective monocentric study of 28 paediatric patients with (PH group) and without PH (control group) who had undergone cardiac catheterisation including OCT imaging of the PA branches. OCT parameters analysed were WT and the quotient of WT and diameter (WT/DM) and those were compared between the PH group and the control group. In addition, the OCT parameters were aligned with the haemodynamic parameters to evaluate the potential of OCT as a risk factor for patients with PH. Results: WT and WT/DM in the PH group were significantly higher compared to the control group {WT: 0.150 [0.230, range (R): 0.100-0.330] vs. 0.100 [0.050, R: 0.080-0.130] mm, P<0.001; WT/DM: 0.06 [0.05] vs. 0.03 [0.01], P=0.006}. There were highly significant correlations between WT and WT/DM with the haemodynamic parameters mean pulmonary arterial pressure (mPAP) [Spearman correlation coefficient (rs) =0.702, P<0.001; rs=0.621, P<0.001], systolic pulmonary arterial pressure (sPAP) (rs=0.668, P<0.001; rs=0.658, P<0.001) and WT and pulmonary vascular resistance (PVR) (rs=0.590, P=0.02). Also, there was a significant correlation between WT and WT/DM and the risk factors quotient of mPAP and mean systemic arterial pressure (mSAP) (mPAP/mSAP) (rs=0.686, P<0.001; rs=0.644, P<0.001) and pulmonary vascular resistance index (PVRI) (rs=0.758, P=0.002; rs=0.594, P=0.02). Conclusions: OCT can detect significant differences in WT of the PA in patients with PH. Furthermore, the OCT parameters correlate significantly with haemodynamic parameters and risk factors for patients with PH. More investigations are required to evaluate to what extent the impact of OCT can contribute to the clinical care of children with PH.

Quality of life and patient satisfaction with outpatient care after heart transplantation in adult and pediatric patients - room for improvement?

Reduced adherence after heart transplantation increases the risk for acute rejection. Therefore, the aim of this study was to evaluate the patient's satisfaction with outpatient care and quality of life (QOL) after pediatric and adult heart transplantation. Observational study after pediatric (n = 22) and adult (n = 65) heart transplantation and the parents of the pediatric patients (n = 22) to evaluate the patients' satisfaction with outpatient care and QOL. Established standardized questionnaires were used for patient satisfaction (ZAP survey) and QOL (SF36); the latter was compared with the cohort of the BGS98 survey (BGS98 cohort). ZAP score: excellent results with almost all values >80. QOL: pediatric cohort showed significantly higher values in physical functioning (P = 0.041) and role physical (P = 0.003) but significantly lower values in the sub-scale general health (P = 0.02) compared to adult cohort. In comparison with BGS98 cohort, children showed almost similar results, whereas adult cohort showed worse values in physical and emotional functioning, but higher values regarding general health. The QOL of patients after pediatric heart transplantation is comparable to a standardized reference population in Germany, whereas adult patients show reduced physical and emotional functioning, but better values regarding general health. The patients' satisfaction with the outpatient care is very high.

Conversion to everolimus in pediatric heart transplant recipients is a safe treatment option with an impact on cardiac allograft vasculopathy and renal function.

BACKGROUND: Cardiac allograft vasculopathy (CAV) and nephrotoxicity affect long-term survival after heart transplantation (HTX). Studies, mostly conducted in adults, showed a positive effect of everolimus (EVL) on these problems. We describe the effects of conversion of the immunosuppressive therapy to an everolimus including regime on CAV, renal function, and safety in heart transplanted children/adolescents. METHODS: This retrospective single-center study included 36 participants (mean time after HTX 6.3 ± 4.7 years). Descriptive pre/post-comparisons were performed with an observation period partially up to 4 years. Impact on CAV was assessed based on intravascular imaging and Stanford grading. Safety analysis included cytomegalovirus (CMV)-infection and acute rejection. RESULTS: In terms of CAV (9 out of 36 patients) four showed no progression, three an improvement, one a worsening; one new diagnosis. The average CrCl showed a significant improvement 6, 12, and 24 months after conversion regarding all patients (n = 29). There was no acute rejection or CMV-infection. CONCLUSION: Conversion to an EVL-based therapy after pediatric HTX is a safe immunosuppressive regime without increasing risk of acute rejection or CMV-infection. There was some evidence of reduction in progression of CAV and a significant improvement of the renal function.

Safety of optical coherence tomography in pediatric heart transplant patients.

BACKGROUND: Cardiac allograft vasculopathy (CAV) is a crucial problem after heart transplantation, in adults as well as in children. CAV is the main risk factor for a reduced long-term graft survival. The early diagnosis and treatment of CAV is essential for a successful long-term preservation of the donor heart. However, asymptomatic progression of CAV and concentric hyperplasia of the coronary arteries may complicate the early diagnosis by conventional measures. Intravascular imaging, such as intravascular ultrasound and optical coherence tomography (OCT), enables the diagnosis of early stage CAV. To date, there is little known about OCT in children. We present our single center experience with OCT after pediatric heart transplantation. METHODS: Retrospective analysis of OCT (n=50) after pediatric heart transplantation between June 2013 and March 2016 and comparison between angiographic appearance and OCT. RESULTS: 37 patients underwent optical coherence tomography, nine patients were examined twice and two patients tree times. The youngest patient at time of examination was 4years with a weight of 15kg (mean 50.86kg, range 15 to 88kg). There were no complications, especially no bleeding, no arrhythmias or myocardial ischemic events. Early CAV (Stanford I or II) was detected by OCT in 26 cases. Only in four of these cases, also the coronary angiography showed mild changes. CONCLUSION: OCT is a safe intravascular imaging method that can also be used in children after pediatric heart transplantation up to a minimum weight of 15kg without an increasing risk of a catheterization procedure.