COVID-19 infection in patients with history of pediatric heart transplant in Germany, Austria, and Switzerland.

COVID-19 is a heterogenous infection-asymptomatic to fatal. While the course of pediatric COVID-19 infections is usually mild or even asymptomatic, individuals after adult heart transplantation are at high risk of a severe infection. We conducted a retrospective, multicenter survey of 16 pediatric heart transplant centers in Germany, Austria and Switzerland to evaluate the risk of a severe COVID-19 infection after pediatric heart transplantation between 02/2020 and 06/2021. Twenty-six subjects (11 male) with a median age of 9.77 years at time of transplantation and a median of 4.65 years after transplantation suffered from COVID-19 infection. The median age at time of COVID-10 infection was 17.20 years. Fourteen subjects had an asymptomatic COVID-19 infection. The most frequent symptoms were myalgia/fatigue (n = 6), cough (n = 5), rhinitis (n = 5), and loss of taste (n = 5). Only one subject showed dyspnea. Eleven individuals needed therapy in an outpatient setting, four subjects were hospitalized. One person needed oxygen supply, none of the subjects needed non-invasive or invasive mechanical ventilation. No specific signs for graft dysfunction were found by non-invasive testing. In pediatric heart transplant subjects, COVID-19 infection was mostly asymptomatic or mild. There were no SARS-CoV-2 associated myocardial dysfunction in heart transplant individuals.

mTor-inhibition within the first days after pediatric heart transplantation is a potentially safe option to prevent cardiac allograft vasculopathy.

BACKGROUND: Immunosuppression after heart transplantation (HTX) with mammalian target of rapamycin (mTOR) inhibitors serves as a prophylaxis against rejection and to treat coronary vascular injury. However, there is little data on the early, preventive use of everolimus after pediatric HTX. METHODS: Retrospective study of 61 pediatric HTX patients (48 cardiomyopathy and 13 congenital heart disease), 28 females, median age 10.1 (range 0.1-17.9) years transplanted between 2008 and 2020. We analyzed survival, rejection, renal function, occurrence of lymphoproliferative disorder, and allograft vasculopathy together with adverse effects of early everolimus therapy combined with low-dose calcineurin inhibitors. RESULTS: Everolimus therapy was started at a median 3.9 (1-14) days after HTX. Median follow-up was 4.3 (range 0.5-11.8) years, cumulative 184 patient years. The estimated 1- and 5-year survival probability was 89% (CI 82%:98%) and 87% (CI 78%:97%). Four patients developed rejection (6.6%) (maximum 2R ISHLT criteria). No patient suffered from chronic renal failure. Three patients (4.9%) developed post-transplant lymphoproliferative disorder. Five patients suffered relevant wound-healing disorders after transplantation, four of them carrying relevant risk factors before HTX (mechanical circulatory support (n = 3), delayed chest closure after HTX (n = 3)). No recipient developed cardiac allograft vasculopathy. CONCLUSION: Initiating everolimus within the first 14 days after HTX seems to be well tolerated, enabling a low incidence of rejection, post-transplant lymphoproliferative disorders, renal failure, and reveals no evidence of cardiac allograft vasculopathy as well as good overall survival in pediatric heart transplant recipients.

Neurological Impact of Slower Rewarming during Bypass Surgery in Infants.

BACKGROUND: Hypothermia is a neuroprotective strategy during cardiopulmonary bypass. Rewarming entailing a rapid rise in cerebral metabolism might lead to secondary neurological sequelae. In this pilot study, we aimed to validate the hypothesis that a slower rewarming rate would lower the risk of cerebral hypoxia and seizures in infants. METHODS: This is a prospective, clinical, single-center study. Infants undergoing cardiac surgery in hypothermia were rewarmed either according to the standard (+1°C in < 5 minutes) or a slow (+1°C in > 5-8 minutes) rewarming strategy. We monitored electrocortical activity via amplitude-integrated electroencephalography (aEEG) and cerebral oxygenation by near-infrared spectroscopy during and after surgery. RESULTS: Fifteen children in the standard rewarming group (age: 13 days [5-251]) were cooled down to 26.6°C (17.2-29.8) and compared with 17 children in the slow-rewarming group (age: 9 days [4-365]) with a minimal temperature of 25.7°C (20.1-31.4). All neonates in both groups (n = 19) exhibited suppressed patterns compared with 28% of the infants > 28 days (p < 0.05). During rewarming, only 26% of the children in the slow-rewarming group revealed suppressed aEEG traces (vs. 41%; p = 0.28). Cerebral oxygenation increased by a median of 3.5% in the slow-rewarming group versus 1.5% in the standard group (p = 0.9). Our slow-rewarming group revealed no aEEG evidence of any postoperative seizures (0 vs. 20%). CONCLUSION: These results might indicate that a slower rewarming rate after hypothermia causes less suppression of electrocortical activity and higher cerebral oxygenation during rewarming, which may imply a reduced risk of postoperative seizures.

De novo gain-of-function variants in KCNT2 as a novel cause of developmental and epileptic encephalopathy.

Variants in several potassium channel genes have been found in developmental and epileptic encephalopathies (DEE). We report on 2 females with de novo variants in KCNT2 with West syndrome followed by Lennox-Gastaut syndrome or with DEE with migrating focal seizures. After in vitro analysis suggested quinidine-responsive gain-of-function effects, we treated 1 of the girls with quinidine add-on therapy and achieved marked clinical improvements. This suggests that the new spectrum of KCNT2-related disorders do not only share similar phenotypic and in vitro functional and pharmacological features with previously known KCNT1-related disorders, but also represents a further example for possible precision medicine approaches. Ann Neurol 2018;83:1198-1204.

Collateral closure in congenital heart defects with Amplatzer vascular plugs: single-center experience and a simplified delivery technique for exceptional cases.

The study describes our experience with Amplatzer Vascular Plugs (AVP2 and 4) and highlights a more refindes telescopic technique for AVP2 delivery. AVPs are well-established occlusion devices for vascular anomalies in congenital heart disease (CHD). The AVP2 is sometimes preferred to the AVP4 due to its shorter length, flat-profiled retention disks, and the availability of larger diameters, but its profile requires a larger inner lumen for safe delivery. The latter may actually hamper access to target lesions. This is a retrospective analysis of all CHD patients treated with the AVP2 and AVP4 between 12/2012 and 12/2015. Target vessels were characterized, measured, and the device-to-vessel diameter ratio calculated. A modified pigtail technique for AVP2 delivery was frequently used: a floppy wire was simply reinforced by the curved tip of a pigtail catheter (instead of the long sheath's dilator) to guide the required delivery sheath towards the desired landing zone. 59 patients with a median age and bodyweight of 3.0 years (range 0.1-75) and 13.8 kg (range 2.5-80) underwent the implantation of 106 plug-devices (30 AVP2, 76 AVP4) in 91 target vessels. Indications for their use were ductus arteriosus (19%), aortopulmonary (43%) as well as venovenous collaterals (34%) and other miscellaneous lesions (4%). The pigtail-supported AVP2 delivery in six patients proved very convenient. No complications occurred. AVPs are excellent devices for embolizing shunt vessels in CHD patients. Here, we describe a simplified telescoping technique for AVP2 delivery to enter curvy target lesions gently and efficiently.

Everolimus-associated perianal ulcers in an eight-month-old heart transplant recipient.

mTOR inhibitors have a wide spectrum of therapeutic applications in adults and children. Little is known, however, about serious adverse effects in children undergoing mTOR inhibitor therapy. Oral ulcers are common and sometimes severe, but no other gastrointestinal involvement has been reported so far. Here we present a case of everolimus-associated perianal ulcers in an eight-month-old infant, 3 months after heart transplantation, which necessitated the drug's discontinuation. In a thorough series of diagnostic tests, we identified no other cause for the progressive perianal ulceration. The recognition and appropriate management of mTOR inhibitors' adverse effects in pediatric patients are essential and remain challenging.

Multicenter Experience With Mechanical Circulatory Support Using a New Diagonal Pump in 233 Children.

Technological innovations in pediatric extracorporeal life support circuits can reduce system-related complications and may improve patients' outcome. The Deltastream DP3 (Medos Medizintechnik AG, Stolberg, Germany) is a novel rotational pump with a diagonally streamed impeller that can be used over a broad range of flows. We collected patient data from seven pediatric centers to conduct a retrospective cohort study. We examined 233 patients whose median age was 1.9 (0-201) months. The DP3 system was used for cardiopulmonary support as veno-arterial extracorporeal membrane oxygenation (ECMO) in 162 patients. Respiratory support via veno-venous ECMO was provided in 63 patients. The pump was used as a ventricular assist device in eight patients. Median supporting time was 5.5 (0.2-69) days and the weaning rate was 72.5%. The discharge home rate was 62% in the pulmonary group versus 55% in the cardiac group. Extracorporeal cardiopulmonary resuscitation was carried out in 24 patients (10%) with a survival to discharge of rate of 37.5%. About 106 (47%) children experienced no complications, while 33% suffered bleeding requiring blood transfusion or surgical intervention. Three patients suffered a fatal cerebral event. Renal replacement therapy was performed in 28% and pump or oxygenator exchange in 26%. Multivariable analysis identified system exchange (OR 1.94), kidney failure (OR 3.43), and complications on support (OR 2.56) as risk factors for dismal outcome. This novel diagonal pump has demonstrated its efficacy in all kinds of mechanical circulatory and respiratory support, revealing good survival rates.

Implementing and Assessing a Standardized Protocol for Weaning Children Successfully From Extracorporeal Life Support.

Extracorporeal life support (ECLS) weaning is a complex interdisciplinary process with no clear guidelines. To assess ventricular and pulmonary function as well as hemodynamics including end-organ recovery during ECLS weaning, we developed a standardized weaning protocol. We reviewed our experience 2 years later to assess its feasibility and efficacy. In 2015 we established an inter-professional, standardized, stepwise protocol for weaning from ECLS. If the patient did not require further surgery, weaning was conducted bedside in the intensive care unit (ICU). Most of the weaning procedures are guided via echocardiography. Data acquisition began at baseline level, followed by four-step course (each step lasting 10 min), entailing flow-reduction and ending 30 min after decannulation. Moreover, data from the preprotocol era are presented. Between May 2015 and 2017, 26 consecutive patients (18 male), median age 177 days (2 days-20 years) required ECLS with median support of 4 (2-11) days. Excluding eight not weanable patients, 21 standardized weaning procedures were protocolled in the remaining 18 children. Our generally successful protocol-guided weaning rate (with at least 24-h survival) was 89%, with a discharge home rate of 58%. Practical application of the novel standard protocol seems to facilitate ECLS weaning and to improve its success rate. The protocol can be administered as part of standard bedside ICU assessment.

Echocardiographic characteristics in Fontan patients before the onset of protein-losing enteropathy or plastic bronchitis.

BACKGROUND: It was this study's objective to evaluate the echocardiographic characteristics and flow patterns in abdominal arteries of Fontan patients before the onset of protein-losing enteropathy (PLE) or plastic bronchitis (PB). DESIGN: In this retrospective cohort investigation, we examined 170 Fontan patients from 32 different centers who had undergone echocardiographic and Doppler ultrasound examinations between June 2006 and May 2013. Follow-up questionnaires were completed by 105 patients a median of 5.3 (1.5-8.5) years later to evaluate whether one of the complications had occurred since the examinations. RESULTS: A total of 91 patients never developed PLE or PB ("non-PLE/PB"); they were compared to 14 affected patients. Eight of the 14 patients had already been diagnosed with "present PLE/PB" when examined. Six "future PLE/PB" patients developed those complications later on and were identified on follow-up. The "future PLE/PB" patients presented significantly slower diastolic flow velocities in the celiac artery (0.1 (0.1-0.5) m/s vs 0.3 (0.1-1.0) m/s (P = .04) and in the superior mesenteric artery (0.0 (0.0-0.2) m/s vs 0.2 (0.0-0.6) m/s, P = .02) than the "non-PLE/PB" group. Median resistance indices in the celiac artery were significantly higher (0.9 (0.8-0.9) m/s vs 0.8 (0.6-0.9) m/s, (P = .01)) even before the onset of PLE or PB. CONCLUSION: An elevated flow resistance in the celiac artery may prevail in Fontan patients before the clinical manifestation of PLE or PB.

European perspective on less invasive surfactant administration-a survey.

Less invasive surfactant administration or minimally invasive surfactant therapy (LISA/MIST) has been proposed for the administration of surfactant in preterm infants without intubation. The aim of our survey was to assess the rate of utilization, premedication as well as technique and equipment used for LISA/MIST. Furthermore, attitudes and experiences in regard to indications, side effects, and efficacy should be assessed. An online-based survey was sent to 324 neonatologists from different centers within 37 European countries between December 2015 and March 2016. Of those 165 who responded (response rate 51%), 86 (52%) were using LISA/MIST. It is regarded the standard procedure for surfactant administration by 41%, with a wide variation in personal views on patient selection in terms of indication, appropriate gestational and postnatal age. Policies concerning premedication, devices, and technique of LISA/MIST differed widely. Side effects like surfactant reflux, bradycardia, and hypoxia were observed by 77% of neonatologists. Of neonatologists inexperienced in LISA/MIST, 89% would consider utilizing it in the future. Perceived efficacy of LISA/MIST was high (52%) to medium (33%). CONCLUSION: The use of LISA/MIST within Europe is widespread. There is a wide variation concerning all aspects of LISA in daily clinical routine and different views on when and how LISA should be performed. What is Known: • Noninvasive surfactant administration has been the subject of randomized controlled trials and has found its way into clinical routine. What is New: • Noninvasive surfactant administration techniques are widely applied in European neonatal units. • There is a wide variety of equipment used and techniques applied for less invasive surfactant delivery as well as different views on the indications and perceived efficacy of this intervention.

Long-Term Follow-Up on Health-Related Quality of Life After Mechanical Circulatory Support in Children.

OBJECTIVE: The objective of this study was to evaluate health-related quality of life in long-term survivors of mechanical circulatory support after acute cardiopulmonary failure. DESIGN: Prospective follow-up study. SETTING: Single-institutional in a center for congenital heart disease and pediatric cardiology. PATIENTS: Fifty patients who underwent 58 mechanical circulatory support therapies in our institution from 2001 to 2012. Median age was 2 (0-213) months, and median supporting time was 5 (1-234) days. Indication groups: 1) extracorporeal life support in low cardiac output: 30 cases (52%); 2) extracorporeal cardiopulmonary resuscitation: 13 cases (22%); 3) extracorporeal membrane oxygenation in acute respiratory distress syndrome: four cases (7%); and 4) ventricular assist devices: 11 cases (19%). INTERVENTIONS: Health-related quality of life was measured using standardized questionnaires according to the age group and completed by either parent proxies in children under 7 years old or the survivors themselves. MEASUREMENTS AND MAIN RESULTS: Fifty percentage of the patients were discharged home, and 22 long-term survivors (44%) were studied prospectively for health-related quality of life. Median follow-up period was 4.5 (0.3-11.3) years. Median age at follow-up was 5 (0.6-29) years old. Nineteen long-term survivors filled in the health-related quality of life questionnaires and were classified into three age groups: 0-4 years (n = 7): median health-related quality of life score, 69 (59-86) points; 4-12 years (n = 7): median health-related quality of life score, 50 (48-85) points; older than 12 years (n = 5): median health-related quality of life score, 90 (80-100) points. CONCLUSION: Long-term survivors' health-related quality of life as reported by their parents is lower than that of healthy children. However, the self-assessed health-related quality of life of the patients older than 12 years in our group is comparable to a healthy control population.

An Early Glenn Operation May be Associated with the Later Occurrence of Protein-Losing Enteropathy in Fontan Patients : Association of Early Glenn and Failing Fontan.

Protein-losing enteropathy (PLE) and plastic bronchitis (PB) are major causes of long-term mortality after Fontan operation. The objective of this study was to determine early clinical risk factors before the onset of PLE and PB. In a cohort study, 106 Fontan patients between 2005 and 2013 were examined. A median of 5.3 (1.5-8.5) years later, follow-up questionnaires were used to group the patients in a PLE or PB group (n = 14) and a non-PLE/PB group (n = 92). Prevalence of PLE was 9.4% (n = 10) and of PB 3.8% (n = 4). At follow-up, five patients (4.7%) died of PLE or PB. Median age at death was 6.2 years (IQR 10.5, 95% CI 5.3-23.4). We observed no significant group differences in gender distribution (p = 0.73), ventricular morphology (p = 0.87), surgical technique (p = 0.64), conduit fenestration (p = 0.34), age at Fontan operation (p = 0.54), and need for diuretics (p = 0.56). Hypoplastic left heart syndrome was more frequent in the PLE/PB group 50 vs. 22.8% (p = 0.03) OR 3.4 (95% CI 1.1-10.8). The modified Glenn procedure was performed at a median age of 4 months (IQR 4.0) in the PLE/PB group versus 8 months (IQR 8.0) in the non-PLE/PB group (p = 0.01). The early Glenn procedure and hypoplastic left heart syndrome may be associated with the development of PLE and PB.

Desmoplakin mutations with palmoplantar keratoderma, woolly hair and cardiomyopathy.

Mutations in genes encoding for desmosomal components are associated with a broad spectrum of phenotypes comprising skin and hair abnormalities and account for 45-50% of cases of arrhythmogenic right ventricular cardiomyopathy. Today, more than 120 dominant and recessive desmoplakin (DSP) gene mutations have been reported to be associated with skin, hair and/or heart defects. Here we report on 3 cases with yet unreported DSP mutations, c.7566_7567delAAinsC, p.R2522Sfs*39, c.7756C>T, p.R2586*, c.2131_2132delAG and c.1067C>A, p.T356K, that were associated with variable woolly hair or hypotrichosis, palmoplantar keratoderma, and cardiac manifestations. In addition, we review and summarise the clinical features and DSP mutations of the patients described in the literature, which illustrates the complexity of this group of disorders and of their genotype-phenotype correlations, which cannot be easily predicted. Early diagnosis is crucial and cardiac examinations have to be performed on a regular basis.

Propofol effect on cerebral oxygenation in children with congenital heart disease.

Propofol is a short-acting, intravenously administered hypnotic agent which is used in procedural sedation in children. Propofol is known to decrease systemic vascular resistance, arterial blood pressure and can lead to desaturations and decreased systemic perfusion in children with cardiac shunting. This may result in a reduction in cerebral blood flow and oxygenation. Near-infrared spectroscopy (NIRS) can monitor cerebral tissue oxygenation in the frontal neocortex. The objective of our study was to measure the changes in cerebral oxygen and blood supply after Propofol infusion in children with congenital heart disease. Propofol infusion may reduce cerebral oxygenation in children with congenital heart disease. The study group consisted of 32 children (f:m = 18:14), with median age of 49 (5-112) months and median weight of 15 (5-34) kg. We performed NIRS derived continuous measurement of cerebral oxygenation and cardiac output using Electrical velocimetry for 5 min before and after sedation with Propofol (1-2 mg/kg i.v.) for cardiac catheterization. Simultaneously, non-invasive arterial blood pressure and transcutaneous oxygen saturation were measured. Propofol sedation led to a significant decrease in mean arterial pressure (79 ± 16 vs. 67 ± 12 mmHg) (p = 0.01) and cardiac index (3.2 ± 0.8 vs. 2.9 ± 0.6 ml/min/m(2)) (p = 0.03). In contrast, cerebral tissue oxygenation index, increased significantly from 57 ± 11 to 59 ± 10 % (p < 0.05). Sedation with Propofol increased cerebral tissue oxygenation despite a decrease in cardiac index and arterial blood pressure. This may be caused by a decreased oxygen consumption of the sedated brain with intact cerebral auto-regulation.

The Yasui procedure with a modified right ventricle-to-pulmonary artery connection utilizing autologous left atrial appendage as a free graft.

A 9-month-old girl born with an interrupted aortic arch type B, an arteria lusoria (aberrant right subclavian artery) and a multilevel left ventricular outflow tract obstruction underwent a Yasui completion after an initial interim palliation. After the Damus-Kaye-Stansel procedure was carried out and the Sano shunt had been established as a source of pulmonary flow, the reported procedure comprised closure of the ventricular septal defect and the intraventricular baffling of left ventricular outflow through a malaligned ventricular septal defect, incision and partial resection of a conal septum and establishment of a right ventricle-to-pulmonary artery connection using an autologous left atrial appendage as a free graft. This technique consisted of dissecting and harvesting the left atrial appendage, which was then used as autologous material for an interposition plasty connecting the central pulmonary artery bifurcation segment with the upper rim of the infundibulotomy. Native, autologous tissue thus comprised the backwall of the newly created right ventricle-to-pulmonary artery continuity. Porcine pericardial patch plasty was then used to complete the remaining circumference of the right ventricle-to-pulmonary artery continuity.

Benefit From a Humanitarian Pediatric Congenital Heart Surgery Program Over a 10-Year Period.

Background: The charity organization Kinderherzen retten e.V. (KHR) enables humanitarian congenital heart surgery for pediatric patients from low- and middle-income countries at the University Heart Center Freiburg, Germany. The aim of this study was to assess periprocedural and mid-term outcomes of these patients for evaluation of KHR sustainability. Methods: Part one of the study comprised retrospective medical chart analyses of the periprocedural course of all KHR-treated children from 2008 to 2017, and part two a prospective evaluation of their mid-term outcome, assessed by questionnaires concerning survival, medical history, mental and physical development, and socioeconomic situation. Results: Of the 100 consecutively presented children from 20 countries (median age 3.25 years), 3 patients were not invasively treatable, 89 underwent cardiovascular surgery, and 8 received a catheter intervention only. There were no periprocedural deaths. Median postoperative duration of mechanical ventilation, intensive care stay, and total hospital stay was 7 (interquartile range [IQR] 4-21) hours, 2 (IQR 1-3) days, and 12 (IQR 10-16) days, respectively. Mid-term postoperative follow-up demonstrated a 5-year survival probability of 94.4%. The majority of patients received continued medical care in their home country (86.2% of patients), were in good mental and physical condition (96.5% and 94.7% of patients, respectively), and able to engage in age-appropriate education/employment (98.3% of patients). Conclusions: Cardiac, neurodevelopmental, and socioeconomic outcomes of patients treated via KHR was satisfactory. Thorough pre-visit evaluation and close contact with local physicians are crucial when providing this high-quality, sustainable, and viable therapeutic option for these patients.

Capability of a new paediatric oesophageal Doppler monitor to detect changes in cardiac output during testing of external pacemakers after cardiac surgery.

BACKGROUND: The Cardio QP™ oesophageal Doppler monitor measures the velocity time integral of the blood flow in the descending aorta. Based on system integrated normograms of the aortic cross-sectional area of a paediatric population, the cardiac output is calculated and displayed. OBJECTIVE: Evaluation of the capability of the Cardio QP™ to detect changes in cardiac output during desynchronizing ventricular pacing (VVI) in children after cardiac surgery. PATIENTS: Eleven children (6 female, 5 male) with epicardial pacemaker electrodes admitted to the paediatric intensive care unit (PICU) after corrective surgery for congenital heart defects. Mean age: 6.3 (2.1-15.0) months, mean body weight: 5.3 (3.5-7.8) kg. INTERVENTIONS: After baseline measurements of cardiac output (base I), we performed 3 steps, each lasting 5 min: (1) ventricular pacing (VVI), (2) baseline (base II) recording, (3) atrial pacing (AOO). We measured the effects on haemodynamic parameters and blood gases as well as on the measured cardiac output. RESULTS: Ventricular pacing, with atrio-ventricular dyssynchrony, led to a significant drop in blood pressure and central venous saturation. Cardiac output parameters showed a decrease in stroke volume (SV) from 4.9±2.2 to 4.2±2.1 ml (P = 0.005) and cardiac index (CI) (2.6±1.1-2.1±0.8 ml/min/m(2)) (P = 0.009) during ventricular pacing. Cardiac index and haemodynamic parameters during atrial stimulation did not show significant changes from baseline. CONCLUSION: The Cardio QP™ seems to be capable of detecting slight changes in cardiac output.

A Rare Case of Severe Dilated Cardiomyopathy in Early Infancy.

We report the case of a 3-month-old girl presenting with end-stage dilated cardiomyopathy and therapy-resistant cardiogenic shock. A left ventricular assist device (LVAD) Berlin Heart EXCOR was implanted, her organs recovered, and she was listed for heart transplantation. Two months later, while still on the LVAD, she was diagnosed with the rare genetic Alström syndrome. Weaning was no option, and she underwent successful heart transplantation at the age of 9 months. The follow-up 15 months later revealed an uneventful transplant course in a child with Alström syndrome.

Ex Vivo Allograft Perfusion for Complex Pediatric Heart Transplant Recipients.

BACKGROUND: Pediatric heart transplant (HTx) recipients with congenital heart defects require complex concomitant surgical procedures with the risk of prolonging the allograft's ischemic time. Ex vivo allograft perfusion with the Organ Care System (OCS; Transmedics, Andover, MA) may improve survival of these challenging patients. METHODS: In this retrospective, single-center study a consecutive series of 8 children with allografts preserved using the OCS was compared with 13 children after HTx with cold storage of the donor heart from March 2018 to March 2020. RESULTS: Median recipient age in the control group was 18 months (range, 1-189) versus 155 months (range, 83-214) in the OCS group, and the baseline differences between the 2 groups were not significant. Fifty percent of the children in the OCS group had complex congenital heart defects (vs 15% of the control subjects). Median operation time during HTx in the OCS group was 616 minutes (range, 270-809) versus 329 minutes (range, 283-617). Because of the time of ex vivo allograft perfusion (265 minutes [range, 202-372]) median total ischemia time was significantly shorter in the OCS group: 78 minutes (range, 52-111) versus 222 minutes (range, 74-326). The incidence of primary graft, renal, or hepatic failure did not differ between the groups. Graft function and the occurrence of any treated rejection at follow-up revealed no significant difference between the 2 groups. One-year survival was 88% in the OCS group (vs 85%). CONCLUSIONS: Ex vivo allograft perfusion enabled complex pediatric HTx, yielding outcomes as positive as those of children whose donor hearts were stored in ice-cold solution.