Search

The machine perfusion (MP) of transplantable grafts has emerged as an upcoming field in Cardiothoracic (CT) transplantation during the last decade. This technology carries the potential to assess, preserve, and even recondition thoracic grafts before transplantation, so it is a possible game-changer in the field. This technology field has reached a critical turning point, with a growing number of publications coming predominantly from a few leading institutions, but still need solid scientific evidence. Due to the increasing need to expand the donor pool, especially in Europe, where the donor age is steeply increased, a consensus has been established to address the growing need and knowledge of machine perfusion in cardiothoracic transplantation, targeting the unmet scientific need in this growing field but also, priorities for development, and regional differences in utilization rates and organizational issues. To address MP in CT, the European Society of Organ Transplantation (ESOT) convened a dedicated Working group comprised of experts in CT to review literature about MP to develop guidelines that were subsequently discussed and voted on during the Consensus Conference that took place in person in Prague during the TLJ 3.0 in November 2022. The findings and recommendations of the Cardiothoracic Working Group on MP are presented in this article.

Background: EXCOR ventricular assist device (VAD) is the gold standard circulatory support for children with end-stage heart failure. Until recently, the only available driving unit was the stationary Ikus. This study (NCT04634708) investigates the impact of the novel mobile EXCOR Active driving unit on patients’ mobility and the quality of life (QoL) of their families. Methods: Children on EXCOR VAD support with the Ikus who were mobilizable outside the hospital room were eligible for the prospective study. Patients remained on Ikus for 7 days, then switched to Excor Active, and were observed for another 45 days. The end-points were the rates of clinically relevant device exchanges (i.e., exchanges that could raise safety concerns for the patient) and successful patient outcomes, respectively. QoL of patients’ families was recorded through 2 validated questionnaires: the Pediatric Quality of Life Inventory Family Impact Module and Depression, Anxiety and Stress Scale 21. Patients’ mobility and activity levels were monitored through diary entries. Results: A total of 24 patients were enrolled of which 23 patients completed the study. No clinically relevant device exchanges occurred and there was a successful outcome in 22/23 (95.7%) patients. Changing from the Ikus to the EXCOR Active improved QoL as seen in family impact total score (from 53.8 ± 19.8-66.5 ± 20.8, p = 0.005) and mental health (depression: moderate to mild, stress moderate to normal, both p

Pediatric patients supported by extracorporeal ventricular assist devices traditionally require long-term stationary inpatient settings. Limited mobility and permanent hospitalization significantly reduce their quality of life. Berlin Heart address this with their novel mobile driving unit, EXCOR® Active. This case report presents its first application outside of Germany, where it was developed, focusing on staff education and safety measures leading to a successful switch of driving units.

We report on a 14-year-old patient who was supported for nearly two years with an ic-LVAD and managed to complete his journey to transplantation without a single complication. Although mechanical assist device support is available for children up to 20 kg in body weight, availability is limited to paracorporeal devices. Intracorporal (ic) left ventricular assist devices (LVADs) for infants in the suitable weight class are a viable option as a bridge-to-transplant, where they make up more than 50% of transplant candidates in their category. A teenager with 59 kg body weight was newly diagnosed with DCM and listed for heart transplantation. After initially being on VA-ECMO, an Abbott HeartMate 3 LVAD with postoperative temporary RVAD support was initialised. RV-support was maintained for 10 days. The further postoperative course was uneventful, and he was discharged on day 98. He was seen regularly in the outpatient department and integrated into school routine again, following the extensive training of his classmates and the responsible school staff. After a total of 672 days on support, he was successfully transplanted. There were no unplanned admissions, thrombotic nor bleeding events, as well as no driveline infection, even though the patient participated in sport classes at school.

Objectives: A self-constructed valved pulmonary conduit made out of a de-cellularized porcine small intestinal submucosal extracellular matrix biological scaffold was tested in a chronic growing lamb model. Methods: The conduit was implanted in pulmonary valve position in 19 lambs. We monitored clinical, laboratory, and echocardiographic findings until 12 months after surgery. In two animals, euthanasia was planned at nine and twelve months. Pre-mortem chest computed tomography and post-mortem pathologic work up were performed. Data are presented as frequency and percentage, median and range, or mean and standard deviation. Results: Twelve (63.2%) animals survived the perioperative period. Three unexpected deaths occurred during the follow-up period: one due to aspiration pneumonia at 23 days after surgery, and two due to early and late infective endocarditis of the conduit at 18 and 256 days. In the two animals with planned scarification, the pre-mortem CT scan revealed mild or no calcification within the conduit or valve leaflets. In the echocardiographic examination at 12 months, peak and mean systolic pressure gradients across the conduit valve were 6.5 (3–21) mmHg and 3 (2–12) mmHg, while valve regurgitation was none (n = 2), trivial (n = 5), moderate (n = 1), or severe (n = 1). No clinical or laboratory signs of hemolysis were seen. After 12 months of follow-up, the animals’ body weights had increased from 33 (27–38) kg to 53 (38–66) kg (p = 0.010). Conclusions: Implantation of a valved pulmonary conduit in our growing lamb model was feasible. Infective endocarditis of the implanted valved conduit remained a significant complication.

Abstract Successful therapy of heart failure with preserved ejection fraction (HFpEF) remains a major unmet clinical need. Device-based treatment approaches include the interatrial shunt device (IASD), conventional assist devices pumping blood from the left ventricle (LV-VAD) or the left atrium (LA-VAD) towards the aorta, and a valveless pulsatile assist device with a single cannula operating in co-pulsation with the native heart (CoPulse). Hemodynamics of two HFpEF subgroups during rest and exercise condition were translated into a lumped parameter model of the cardiovascular system. The numerical model was applied to assess the hemodynamic effect of each of the four device-based therapies. All four therapy options show a reduction in left atrial pressure during rest and exercise and in both subgroups (> 20%). IASDs concomitantly reduce cardiac output (CO) and shift the hemodynamic overload towards the pulmonary circulation. All three mechanical assist devices increase CO while reducing sympathetic activity. LV-VADs reduce end-systolic volume, indicating a high risk for suction events. The heterogeneity of the HFpEF population requires an individualized therapy approach based on the underlying hemodynamics. Whereas phenotypes with preserved CO may benefit most from an IASD device, HFpEF patients with reduced CO may be candidates for mechanical assist devices.

Purpose: The withdrawal of HVAD in 2021 created a concern for the pediatric population. The alternative implantable centrifugal blood pump HeartMate 3 has since been used more frequently in children. This paper analyses the outcome of children on LVAD support provided with an HVAD or HM3. Methods: A retrospective analysis of the EUROMACS database on children supported with VAD < 19 years of age from 1 January 2009 to 1 December 2021 was conducted. All patients with an LVAD and either an HVAD or HM3 were included. Patients with missing data on VAD status and/or missing baseline and/or follow up information were excluded. Kaplan–Meier survival analysis was performed to evaluate survival differences. Analyses were performed using Fisher’s exact test. Results: The study included 150 implantations in 142 patients with 128 implants using an HVAD compared to 28 implants using an HM3. Nine patients (6%) needed temporary right ventricular mechanical support, which was significantly higher in the HM3 group, with 25% (p: 0.01). Patients in the HVAD group were significantly younger (12.7 vs. 14.5 years, p: 0.01), weighed less (45.7 vs. 60 kg, p: 2, p: p: ns). A total of 123 children (86%) survived to transplantation, recovery or are ongoing, without differences between groups. In the HVAD group, 10 patients (8%) died while on support, whereas in 12% of HM3 patients died (p: 0.7). Conclusions: Survival in children implanted with an HM3 was excellent. Almost 90% were discharged and sent home on the device.

For children born with congenital heart defects (CHDs), extracorporeal life support may be necessary. This retrospective single-center study aimed to investigate the outcomes of children with CHDs on extracorporeal membrane oxygenation (ECMO), focusing on various risk factors. Among the 88 patients, 36 (41%) had a single-ventricle heart defect, while 52 (59%) had a biventricular defect. In total, 25 (28%) survived, with 7 (8%) in the first group and 18 (20%) in the latter. A p-value of 0.19 indicated no significant difference in survival rates. Children with biventricular hearts had shorter ECMO durations but longer stays in the intensive care unit. The overall rate of complications on ECMO was higher in children with a single ventricle (odds ratio [OR] 1.57, 95% confidence interval [CI] 0.67–3.7); bleeding was the most common complication in both groups. The occurrence of a second ECMO run was more frequent in patients with a single ventricle (22% vs. 9.6%). ECMO can be effective for children with congenital heart defects, including single-ventricle patients. Bleeding remains a serious complication associated with worse outcomes. Patients requiring a second ECMO run within 30 days have lower survival rates.

Background: In neonates with critical aortic coarctation (CoA) primary stenting of CoA may serve as therapeutic bridging until definitive surgical repair. Methods: Comparative study of acute and long-term outcome of neonates with critical CoA treated by combined stent-surgery approach, or by primary surgery. Complications, re-intervention rate, clinical and echocardiographic findings of left ventricular (LV) function were compared. Results: Between 2012 and 2014, we treated 20 neonates at a median age of 9 (7–51) days and a body weight of 3.6 (3–4.1) kg. We compared 10 neonates treated by primary CoA stenting and secondary surgery with stent removal and CoA repair with 10 age-matched infants with primary surgical CoA repair. There was no early or late mortality. Perioperative complications and rate of re-intervention were comparable in both groups. LV function was reduced before first intervention ejection fraction (EF) 39% (30–42), shortening fraction 27% (20–32), more affected in the stent group, but recovered after stenting until secondary surgery (EF 30% vs. EF 40%, p = 0.01) and normalized until last follow-up (EF 62%, p

Abstract The previously more frequently implanted pulsatile blood pumps (PBPs) showed higher recovery rates than the currently preferred rotary blood pumps (RBPs), with unclear causality. The aim of this study was to comparatively assess the capability of PBPs and RPBs to unload the left ventricle and maintain cardiac energetics as a possible implication for recovery. An RBP and a heartbeat synchronized PBP were alternately connected to isolated porcine hearts. Rotational speed of RBPs was set to different support levels. For PBP support, the start of ejection was phased to different points during the cardiac cycle, prescribed as percentage delays from 0% to 90%. Cardiac efficiency, quantified by the ratio of external work over myocardial oxygen consumption, was determined. For RBP support, higher degrees of RBP support correlated with lower left atrial pressures (LAP) and lower cardiac efficiency (r = 0.91 ± 0.12). In contrast, depending on the phase delay of a PBP, LAP and cardiac efficiency exhibited a sinusoidal relationship with the LAP minimum at 90% and efficiency maximum at 60%. Phasing of a PBP offers the possibility to maintain a high cardiac efficiency and simultaneously unload the ventricle. These results warrant future studies investigating whether optimized cardiac energetics promotes functional recovery with LVAD therapy.

Veno-arterial extracorporeal membrane oxygenation (V-A ECMO) is frequently used in children with and without congenital heart disease (CHD). This study, of a single-center and retrospective design, evaluated the use and timing of V-A ECMO in a pediatric cohort who underwent V-A ECMO implantation between January 2009 and December 2019. The patients were divided into a pre-/non-surgical group and a post-surgical group. Among the investigated variables were age, gender, weight, duration of ECMO, ECMO indication, and ventricular physiology, with only the latter being statistically relevant between the two groups. A total of 111 children (58 male/53 female), with a median age of 87 days (IQR: 7–623) were supported using V-A ECMO. The pre-/non-surgical group consisted of 59 patients and the post-surgical group of 52 patients. Survival at discharge was 49% for the pre-/non-surgical group and 21% for the surgical group (p = 0.04). Single-ventricle physiology was significant for a worse outcome (p = 0.0193). Heart anatomy still has the biggest role in the outcomes of children on ECMO. Nevertheless, children with CHD can be successfully bridged with ECMO to cardiac operation.

OBJECTIVES Extracorporeal membrane oxygenation (ECMO) has become an essential life-saving tool. Being resource-intensive, judicious use and optimising the outcomes of this precious resource is important. This retrospective, explanatory, observational study aimed to quantify associations between factors and outcome after pulmonary ECMO in children. METHODS This study included 39 consecutive ECMO runs in 38 children performed for pulmonary indications at our hospital from 2008 to 2018. Indications included acute respiratory distress syndrome, infection, drowning, meconium aspiration and pulmonary hypertension, among others. Depending on the need for haemodynamic support, 21 patients (53.8%) received veno-venous ECMO, while 18 (46.2%) received veno-arterial ECMO. We sought to compare the 11 non-survivors with the 27 survivors with respect to time-independent and time-dependent variables. Logistic regression models and Cox proportional hazards models were used. Threshold analysis was done using the “minimum p-value approach”. RESULTS 27/39 (69%) ECMO runs could be weaned; 27/38 (71%) patients were discharged. 20/27 (74%) survivors had unremarkable neurological status, six (22%) had mild findings (convulsions, muscular hypotony, neuropathy) and one (4%) had a hemi-syndrome at discharge. Univariate analyses showed a hazard ratio (HR) of 0.48 for log(pH) (95% confidence interval [CI] 0.22 to 1.02, p = 0.055) and an HR of 4.48 for log(lactate) (95% CI 1.92 to 10.48, p = 0.0005). Multivariate models showed an HR of 0.99 for log(pH) (95% CI 0.43 to 2.26, p = 0.98) and an HR of 4.44 for log(lactate) (95% CI 1.65 to 11.95, p = 0.003). Threshold analysis showed lactate >4.1 to be associated with mortality, with an HR of 32.7 (95% CI 4.8 to 221.7, p = 0.0002). This threshold should, however, be interpreted very cautiously. Evidence of an association between serum lactate at 24 hours and mortality was found (difference between survivors and non-survivors: −2.78, 95% CI −5.36 to −0.20, p = 0.037). CONCLUSIONS The results of ECMO for pulmonary indications are very good. Serum lactate may be an early prognostic indicator.

In chronic cardiomyopathy, mechanical circulatory support plays an increasingly important role for children as the shortage of suitable donor hearts increases times on the transplant waiting list. Ventricular assist devices (VADs) for adults have evolved dramatically over the last decade, both as a bridge to transplantation and for permanent support. In contrast, VADs designed for children, especially for all age groups, are still in their infancy. The Medos HIA and the Berlin Heart Excor are specially designed for children with a body surface area

We introduce a GPU-accelerated finite element forward solver for the computation of light transport in scattering media. The forward model is the computationally most expensive component of iterative methods for image reconstruction in diffuse optical tomography, and performance optimisation of the forward solver is therefore crucial for improving the efficiency of the solution of the inverse problem. The GPU forward solver uses a CUDA implementation that evaluates on the graphics hardware the sparse linear system arising in the finite element formulation of the diffusion equation. We present solutions for both time-domain and frequency-domain problems. A comparison with a CPU-based implementation shows significant performance gains of the graphics accelerated solution, with improvements of approximately a factor of 10 for double-precision computations, and factors beyond 20 for single-precision computations. The gains are also shown to be dependent on the mesh complexity, where the largest gains are achieved for high mesh resolutions.