Berlin Heart EXCOR pediatric ventricular assist device for bridge to heart transplantation in US children

First North American experience with the Berlin Heart EXCOR Active driver

For smaller pediatric patients on ventricular assist devices, the Berlin Heart EXCOR remains the main form of durable support. It requires a connection to the external IKUS, which has limited portability and battery life. The new EXCOR Active mobile driving unit has a battery life of up to 13 hours. We describe the first North American experience with the EXCOR Active in pediatric patients with a Berlin Heart device. A retrospective chart review was undertaken. Between October 2022 and March 2024, 7 patients were on a Berlin Heart and supported with the EXCOR Active. All patients were initially supported with the IKUS with a median time to transition to the EXCOR Active of 12.0 days (interquartile range [IQR] 9.5, 18.5) and a median time of support with the EXCOR Active of 65.0 days (IQR, 32.0, 81.0). The EXCOR Active posed no significant safety issues, and minimal operating issues were noted. Following the transition from IKUS to the EXCOR Active, there was increased patient and caregiver mobility throughout the hospital. Use of the EXCOR Active has the potential to improve the quality of life in pediatric patients waiting for heart transplantation.

They Deserve to Live: Impact of the Berlin Heart EXCOR on Small Children's Heart Transplant Waitlist in Low-Resource Settings

Background: In newly emerging economy countries, the shortage of pediatric donor hearts and poor healthcare infrastructure poses a significant challenge. Although mechanical circulatory support (MCS) has been proven effective in enhancing heart transplant waiting list outcomes, economic barriers hinder its widespread adoption. Methods: A single-center retrospective study reviewed children under 10 kg on the heart transplant (HTx) list from 2012 to 2023. Elective or priority status was assigned based on their clinical condition at the time of transplant. In cases of clinical decompensation, centrifugal pump and extracorporeal membrane oxygenation, transitioned to the Berlin Heart EXCOR (BHE) pediatric ventricular assist device (VAD) was employed. Pre- and post-HTx outcomes were analyzed with descriptive statistics, Cox regression, and competing survival risks. Results: Out of 81 infants on the HTx list, 61.7% (50/81) were in critical condition. The median wait time was 224 days, and 34% (28/81) died while waiting. Out of 37 transplanted patients, 6 (16%) had graft dysfunction, and 10 (27%) had acute renal injury. Survival to discharge was 84% (31/37). Patients who received the BHE exhibited higher chances of receiving a transplant (hazard ratio: 2.3; 95% confidence interval: 1.2-4.6; P = .01). Priority status or MCS use did not significantly impact mortality post-transplant. Conclusion: Advanced MCS technologies can potentially reduce the mortality risk on the pediatric HTx waitlist. The findings highlight the significant waiting time for HTx and the critical role of the BHE in improving outcomes in children, particularly those under 10 kg. The results advocate for the adoption of ventricular assist devices as a viable interim solution to bridge critically ill children to HTx, ultimately enhancing their chances of survival despite limited donor heart availability.

Development of the PSU Child Pump

The Pennsylvania State University (PSU) Child Pump, a centrifugal continuous-flow ventricular assist device (cf-VAD), is being developed as a suitable long-term implantable device for pediatric heart failure patients between 10 and 35 kg, body surface area (BSA) of 0.5-1.2 m 2 , 1-11 years of age, and requiring a mean cardiac output of 1.0-3.5 L/min. In-vitro hydraulic and hemodynamic performances were evaluated on a custom mock circulatory loop with ovine blood. Normalized index of hemolysis (NIH) was evaluated under four conditions: 1) 8,300 rpm, 3.5 L/min, Δ P = 60 mm Hg, 2) 8,150 rpm, 5.1 L/min, Δ P = 20 mm Hg, 3) 8,400 rpm, 3.2 L/min, Δ P = 70 mm Hg, and 4) 9,850 rpm, 5.0 L/min, Δ P = 80 mm Hg, resulting in normalized index of hemolysis = 0.027 ± 0.013, 0.015 ± 0.006, 0.016 ± 0.008, and 0.026 ± 0.011 mg/dl, respectively. A mock fit study was conducted using a three-dimensional printed model of a 19 kg patient's thoracic cavity to compare the size of the PSU Child Pump to the HeartMate3 and the HVAD. Results indicate the PSU Child Pump will be a safer, appropriately sized device capable of providing the given patient cohort proper support while minimizing the risks of blood trauma as they wait for a transplant.

International Society for Heart and Lung Transplantation Guidelines for the Evaluation and Care of Cardiac Transplant Candidates-2024

The "International Society for Heart and Lung Transplantation Guidelines for the Evaluation and Care of Cardiac Transplant Candidates-2024" updates and replaces the "Listing Criteria for Heart Transplantation: International Society for Heart and Lung Transplantation Guidelines for the Care of Cardiac Transplant Candidates-2006" and the "2016 International Society for Heart Lung Transplantation Listing Criteria for Heart Transplantation: A 10-year Update." The document aims to provide tools to help integrate the numerous variables involved in evaluating patients for transplantation, emphasizing updating the collaborative treatment while waiting for a transplant. There have been significant practice-changing developments in the care of heart transplant recipients since the publication of the International Society for Heart and Lung Transplantation (ISHLT) guidelines in 2006 and the 10-year update in 2016. The changes pertain to 3 aspects of heart transplantation: (1) patient selection criteria, (2) care of selected patient populations, and (3) durable mechanical support. To address these issues, 3 task forces were assembled. Each task force was cochaired by a pediatric heart transplant physician with the specific mandate to highlight issues unique to the pediatric heart transplant population and ensure their adequate representation. This guideline was harmonized with other ISHLT guidelines published through November 2023. The 2024 ISHLT guidelines for the evaluation and care of cardiac transplant candidates provide recommendations based on contemporary scientific evidence and patient management flow diagrams. The American College of Cardiology and American Heart Association modular knowledge chunk format has been implemented, allowing guideline information to be grouped into discrete packages (or modules) of information on a disease-specific topic or management issue. Aiming to improve the quality of care for heart transplant candidates, the recommendations present an evidence-based approach.

Fluid Dynamic Study of the Penn State Pediatric Total Artificial Heart

Penn State University is developing a pediatric total artificial heart (TAH) as a bridge-to-transplant device that supports infants and small children with single ventricle anomalies or biventricular heart failure to address high waitlist mortality rates for pediatric patients with severe congenital heart disease (CHD). Two issues with mechanical circulatory support devices are thrombus formation and thromboembolic events. This in vitro study characterizes flow within Penn State's pediatric total artificial heart under physiological operating conditions. Particle image velocimetry (PIV) is used to quantify flow within the pump and to calculate wall shear rates (WSRs) along the internal pump surface to identify potential thrombogenic regions. Results show that the diastolic inflow jets produce sufficient wall shear rates to reduce thrombus deposition potential along the inlet side of the left and right pumps. The inlet jet transitions to rotational flow, which promotes wall washing along the apex of the pumps, prevents flow stasis, and aligns flow with the outlet valve prior to systolic ejection. However, inconsistent high wall shear rates near the pump apex cause increased thrombogenic potential. Strong systolic outflow jets produce high wall shear rates near the outlet valve to reduce thrombus deposition risk. The right pump, which has a modified outlet port angle to improve anatomical fit, produces lower wall shear rates and higher thrombus susceptibility potential (TSP) compared to the left pump. In summary, this study provides a fluid dynamic understanding of a new pediatric total artificial heart and indicates thrombus susceptibility is primarily confined to the apex, consistent with similar pulsatile heart pumps.

Predicting Stroke for Pediatric Patients Supported With Ventricular Assist Devices: A Pedimacs Report

BACKGROUND

The Pediatric Interagency Registry for Mechanical Circulatory Support (Pedimacs) provides detailed understanding on pediatric patients supported with ventricular assist devices (VADs). We sought to identify important variables affecting the incidence of stroke in pediatric VADs.

METHODS

Between 2012 and 2022, 1463 devices in 1219 patients were reported to Pedimacs from 40 centers in patients aged <19 years at their first VAD implantation. Multiphase parametric hazard modeling was used to identify risk factors for stroke among all device types.

RESULTS

Of the 1219 patients, the most common devices were implantable continuous (472 [39%]), followed by paracorporeal pulsatile (342 [28%]), and paracorporeal continuous (327 [27%]). Overall freedom from stroke at 6 months was higher in the recent era (2012-2016; 80.2% [95% CI, 77.1%-82.9%] vs 2017-2023; 87.9% [95% CI, 86.2%-89.4%], P = .009). Implantable continuous VADs had the highest freedom from stroke at 3 months (92.7%; 95% CI, 91.1%-93.9%) and 6 months (91.1%; 95% CI, 89.3%-92.6%), followed by paracorporeal pulsatile (87.0% [95% CI, 84.8%-88.9%] and 82.8% [95% CI, 79.8%-85.5%], respectively), and paracorporeal continuous (76.0% [95% CI, 71.8%-79.5%] and 69.5% [95% CI, 63.4%-74.8%], respectively) VADs. Parametric modeling identified risk factors for stoke early after implant and later. Overall, and particularly for paracorporeal pulsatile devices, early stroke risk has decreased in the most recent era (hazard ratio, 5.01). Among implantable continuous devices, cardiogenic shock was the major risk factor. For patients <10 kg, early hazard was only seen in the previous era. For congenital patients, early hazard was seen in nonimplantable device use and use of extracorporeal membrane oxygenation.

CONCLUSIONS

The overall stroke rate has decreased from 20% to 15% at 6 months, with particular improvement among paracorporeal pulsatile devices. Risk factor analyses offer insights for identification of higher stroke risk subsets and further management refinements.

Assessment of haemolysis models for a positive-displacement total artificial heart

The assessment and reduction of haemolysis within mechanical circulatory support (MCS) remains a concern with regard to device safety and regulatory approval. Numerical methods for predicting haemolysis have typically been applied to rotary MCS devices and the extent to which these methods apply to positive-displacement MCS is unclear. The aim of this study was to evaluate the suitability of these methods for assessing haemolysis in positive-displacement blood pumps. Eulerian scalar-transport and Lagrangian particle-tracking approaches derived from the shear-based power-law relationship were used to calculate haemolysis in a computational fluid dynamics model of the Realheart total artificial heart. A range of power-law constants and their effect on simulated haemolysis were also investigated. Both Eulerian and Lagrangian methods identified the same key mechanism of haemolysis: leakage flow through the bileaflet valves. Whilst the magnitude of haemolysis varied with different power-law constants, the method of haemolysis generation remained consistent. The Eulerian method was more robust and reliable at identifying sites of haemolysis generation, as it was able to capture the persistent leakage flow throughout the entire pumping cycle. This study paves the way for different positive-displacement MCS devices to be compared across different operating conditions, enabling the optimisation of these pumps for improved patient outcomes.

EXCOR membrane motion analyzer (EMMA) to quantify and assess hemodynamic performance of the EXCOR pediatric heart assist device

BACKGROUND

Pediatric heart failure is associated with high mortality rates and is a current clinical burden. There is only one FDA approved pediatric VAD, Berlin Heart EXCOR, for treatment. Thrombo-embolic complications are a significant clinical challenge, which can lead to devastating complications such as stroke and impair efficient EXCOR function. Currently, clinicians perform largely qualitative periodic assessment of EXCOR operation by observing the motion of a rapidly moving membrane, which can be prone to human error and can lead to missing out on crucial information.

METHODS

In this study, we design and implement a quantitative early warning system for accurate and quantitative assessment of the EXCOR membrane, named EXCOR Membrane Motion Analyzer (EMMA). Using a combination of image analysis, computer vision and custom designed algorithm, we perform rigorous frame by frame analysis of EXCOR membrane video data. We developed specialized metrics to identify relative smoothness between successive peaks, time between peaks and overall smoothness indicators to quantify and compare between multiple cases.

RESULTS

Our results demonstrate that EMMA can successfully identify the motion and wrinkles on each video frame and quantify the smoothness and identify the phases of each cardiac cycle. Moreover, EMMA can obtain the smoothness of each frame and the temporal evolution of membrane smoothness across all image frames for the video sequence.

CONCLUSIONS

EMMA allows for a fast, accurate, quantitative assessment to be completed and reduces user error. This enables EMMA to be used effectively as an early warning system to rapidly identify device abnormalities.

The International Society for Heart and Lung Transplantation (ISHLT): 2024 infection definitions for durable and acute mechanical circulatory support devices

Infections remain a significant concern in patients receiving mechanical circulatory support (MCS), encompassing both durable and acute devices. This consensus manuscript provides updated definitions for infections associated with durable MCS devices and new definitions for infections in acute MCS, integrating a comprehensive review of existing literature and collaborative discussions among multidisciplinary specialists. By establishing consensus definitions, we seek to enhance clinical care, facilitate consistent reporting in research studies, and ultimately improve outcomes for patients receiving MCS.

A prospective multicenter feasibility study of a miniaturized implantable continuous flow ventricular assist device in smaller children with heart failure

BACKGROUND

There is no FDA-approved left ventricular assist device (LVAD) for smaller children permitting routine hospital discharge. Smaller children supported with LVADs typically remain hospitalized for months awaiting heart transplant-a major burden for families and a challenge for hospitals. We describe the initial outcomes of the Jarvik 2015, a miniaturized implantable continuous flow LVAD, in the NHLBI-funded Pumps for Kids, Infants, and Neonates (PumpKIN) study, for bridge-to-heart transplant.

METHODS

Children weighing 8 to 30 kg with severe systolic heart failure and failing optimal medical therapy were recruited at 7 centers in the United States. Patients with severe right heart failure and single-ventricle congenital heart disease were excluded. The primary feasibility endpoint was survival to 30 days without severe stroke or non-operational device failure.

RESULTS

Of 7 children implanted, the median age was 2.2 (range 0.7, 7.1) years, median weight 10 (8.2 to 20.7) kilograms; 86% had dilated cardiomyopathy; 29% were INTERMACS profile 1. The median duration of Jarvik 2015 support was 149 (range 5 to 188) days where all 7 children survived including 5 to heart transplant, 1 to recovery, and 1 to conversion to a paracorporeal device. One patient experienced an ischemic stroke on day 53 of device support in the setting of myocardial recovery. One patient required ECMO support for intractable ventricular arrhythmias and was eventually transplanted from paracorporeal biventricular VAD support. The median pump speed was 1600 RPM with power ranging from 1-4 Watts. The median plasma free hemoglobin was 19, 30, 19 and 30 mg/dL at 7, 30, 90 and 180 days or time of explant, respectively. All patients reached the primary feasibility endpoint. Patient-reported outcomes with the device were favorable with respect to participation in a full range of activities. Due to financial issues with the manufacturer, the study was suspended after consent of the eighth patient.

CONCLUSION

The Jarvik 2015 LVAD appears to hold important promise as an implantable continuous flow device for smaller children that may support hospital discharge. The FDA has approved the device to proceed to a 22-subject pivotal trial. Whether this device will survive to commercialization remains unclear because of the financial challenges faced by industry seeking to develop pediatric medical devices. (Supported by NIH/NHLBI HHS Contract N268201200001I, clinicaltrials.gov 02954497).

A single-institutional experience with 36 children less than 5 kilograms supported with the Berlin Heart: Comparison of congenital versus acquired heart disease

OBJECTIVES

We reviewed outcomes in all 36 consecutive children <5 kg supported with the Berlin Heart pulsatile ventricular assist device at the University of Florida, comparing those with acquired heart disease (n = 8) to those with congenital heart disease (CHD) (n = 28).

METHODS

The primary outcome was mortality. The Kaplan-Meier method and log-rank tests were used to assess group differences in long-term survival after ventricular assist device insertion. T-tests using estimated survival proportions were used to compare groups at specific time points.

RESULTS

Of 82 patients supported with the Berlin Heart at our institution, 49 (49/82 = 59.76%) weighed <10 kg and 36 (36/82 = 43.90%) weighed <5 kg. Of 36 patients <5 kg, 26 (26/36 = 72.22%) were successfully bridged to transplantation. (The duration of support with ventricular assist device for these 36 patients <5 kg was [days]: median = 109, range = 4-305.) Eight out of 36 patients <5 kg had acquired heart disease, and all eight [8/8 = 100%] were successfully bridged to transplantation. (The duration of support with ventricular assist device for these 8 patients <5 kg with acquired heart disease was [days]: median = 50, range = 9-130.) Twenty-eight of 36 patients <5 kg had congenital heart disease. Eighteen of these 28 [64.3%] were successfully bridged to transplantation. (The duration of support with ventricular assist device for these 28 patients <5 kg with congenital heart disease was [days]: median = 136, range = 4-305.) For all 36 patients who weighed <5 kg: 1-year survival estimate after ventricular assist device insertion = 62.7% (95% confidence interval = 48.5-81.2%) and 5-year survival estimate after ventricular assist device insertion = 58.5% (95% confidence interval = 43.8-78.3%). One-year survival after ventricular assist device insertion = 87.5% (95% confidence interval = 67.3-99.9%) in acquired heart disease and 55.6% (95% confidence interval = 39.5-78.2%) in CHD, P = 0.036. Five-year survival after ventricular assist device insertion = 87.5% (95% confidence interval = 67.3-99.9%) in acquired heart disease and 48.6% (95% confidence interval = 31.6-74.8%) in CHD, P = 0.014.

CONCLUSION

Pulsatile ventricular assist device facilitates bridge to transplantation in neonates and infants weighing <5 kg; however, survival after ventricular assist device insertion in these small patients is less in those with CHD in comparison to those with acquired heart disease.

Successful explantation of children from the Berlin Heart EXCOR® ventricular assist device: A systematic review

BACKGROUND

The Berlin Heart EXCOR® (BHE) can bridge children with severe heart failure to transplantation, but some are successfully weaned and spared transplantation. This study seeks to identify characteristics of children amenable to successful explantation with BHE support.

METHODS

Preferred Reporting Items for Systematic reviews and Meta-Analyses 2020 guidelines were used. Five databases were screened for original, English articles measuring BHE support in patients <18 years old based on title and abstract. Exclusion criteria were applied: full-text availability, <10 total pediatric BHE patients, zero successful explantations from BHE, nonprimary literature, adult and pediatric results that could not be separated, and studies with overlapping patient information. Studies were analyzed with descriptive statistics.

RESULTS

From 41 857 potential studies, 14 were analyzed with data from 58 hospitals on four continents from 1990 to 2020. There were 984 BHE patients. The most common diagnosis was dilated cardiomyopathy (n = 318, 32.3%), followed by congenital heart disease (n = 249, 25.3%). There were 85 (8.6%) children explanted with favorable outcomes. The underlying diagnosis was known in 44 (51.8%) cases: 14 (8.4%) of 166 cardiomyopathies, 17 (48.6%) of 35 myocarditis, and 12 (16.7%) of 72 with congenital heart disease were explanted. When the type of support was known, the rate of LVAD patients explanted was 21.3% (n = 19/89) and 2.4% (n = 1/42) of BiVAD patients were explanted.

CONCLUSION

Explantation from BHE is not uncommon at 8.6%, but significant variation exists in the explantation data reported. Myocarditis and LVAD support may be populations suitable for weaning. Standardization of reporting measures and prospective registries may help identify patients suitable for this alternative to transplant and help develop weaning protocols.

Case Report: Sustained ventricular arrhythmia in a child supported by a Berlin heart EXCOR ventricular assist device

Mechanical circulatory support is an established therapy to support failing hearts as a bridge to transplantation. Although tolerated overall, arrhythmias may occur after ventricular assist device implantation and can complicate patient management. We report on an infant with dilated cardiomyopathy who developed ventricular tachycardia followed by recalcitrant ventricular fibrillation, refractory to comprehensive medical therapy post Berlin Heart EXCOR® (BHE) implant.

Mechanical Circulatory Support in Pediatric Myocarditis: Support Strategies and Outcomes in a Nationally Representative Cohort

Background

Myocarditis is a common cause of pediatric heart failure which may require mechanical circulatory support (MCS). The purpose of this study is to describe MCS strategies used in a nationwide cohort of pediatric patients with myocarditis, identify trends over time, and compare outcomes between MCS strategies.

Methods

This study utilized the Kids' Inpatient Database (KID), a national sample of administrative discharge data. KID admissions from 2003-2016 were queried using ICD-9/10 codes to identify those with a diagnosis of myocarditis. MCS outcomes were compared using logistic regression.

Results

Of 5,661 admissions for myocarditis, MCS was used in 424 (7.5%), comprised of extracorporeal membrane oxygenation (ECMO) in 312 (73.6%), including 32 (10.2%) instances of extracorporeal cardiopulmonary resuscitation (ECPR), temporary ventricular assist devices (tVAD) in 28 (6.6%), durable VAD (dVAD) in 42 (9.9%) and combination MCS in 42 (9.9%). MCS use increased over time (p=0.031), but MCS strategies did not significantly change. Mortality was high in the MCS group (28.3%). There was no difference in odds of death in the VAD only or combination MCS group compared to the non-ECPR ECMO group (p=0.07 and p=0.65, respectively).

Conclusion

MCS is used in 1 in 13 pediatric myocarditis cases, and MCS use is increasing over time with ECMO remaining the most frequently used modality. Mortality remains high in patients that receive MCS but does not differ between those receiving VAD or combination MCS as compared to non-ECPR ECMO on unadjusted analysis. Further prospective analysis is required to evaluate the relative effectiveness of MCS modalities in this disease.

Developments and Challenges in Durable Ventricular Assist Device Technology: A Comprehensive Review with a Focus on Advancements in China

Heart transplantation is currently the most effective treatment for end-stage heart failure; however, the shortage in donor hearts constrains the undertaking of transplantation. Mechanical circulatory support (MCS) technology has made rapid progress in recent years, providing diverse therapeutic options and alleviating the dilemma of donor heart shortage. The ventricular assist device (VAD), as an important category of MCS, demonstrates promising applications in bridging heart transplantation, destination therapy, and bridge-to-decision. VADs can be categorized as durable VADs (dVADs) and temporary VADs (tVADs), according to the duration of assistance. With the technological advancement and clinical application experience accumulated, VADs have been developed in biocompatible, lightweight, bionic, and intelligent ways. In this review, we summarize the development history of VADs, focusing on the mechanism and application status of dVADs in detail, and further discuss the research progress and use of VADs in China.

Pediatric mechanical circulatory support - a review

The history of mechanical circulatory support began in 1953, as the first heart-lung machine enabled surgeons to perform complex open heart surgery. Heart failure is more prevalent in adults than pediatric patients which has led to the development of devices for adults with end-stage heart failure at a faster pace. Pediatric mechanical circulatory support has been derived from adult durable devices and subsequently applied in the adolescent population. The application of adult devices in children is inherently problematic due to size mismatch, especially in smaller patients. There has been an increasing interest in developing durable pumps that are appropriate for children for several reasons, with the primary factor being the number of children with end-stage heart failure far exceeding the number of potential donors. Mechanical circulatory support (MCS) for children can be divided into short-term temporary support and long-term durable support. The goal of this review is to discuss the devices available for the pediatric population and review the options for support in complex patients including single-ventricle anatomy, biventricular support, and total artificial heart options. We will also briefly discuss the Pumps for Kids, Infants, and Neonates (PumpKIN) Trial and MCS registries, including the Advanced Cardiac Therapies Improving Outcomes Network (ACTION).

Current treatment outcomes of congenital heart disease and future perspectives

China has the largest number of individuals with congenital heart disease (CHD) in the world and a heavy burden of CHD. Therefore, understanding current CHD treatment outcomes and patterns in China will contribute to global progress in CHD treatment and be a valuable experience. Generally, CHD treatment in China has satisfactory outcomes owing to the joint efforts by all relevant stakeholders across the country. However, efforts are needed to overcome the remaining challenges: management of mitral valve disease and paediatric end-stage heart failure needs to be improved; cohesive paediatric cardiology teams should be established and collaboration between hospitals enhanced; CHD-related medical resources need to be more accessible and equitable; and nationwide CHD databases should be enhanced. In the second paper of this Series, we aim to systematically summarise the current CHD treatment outcomes in China, discuss potential solutions, and provide future perspectives.

Machine learning based on computational fluid dynamics enables geometric design optimisation of the NeoVAD blades

The NeoVAD is a proposed paediatric axial-flow Left Ventricular Assist Device (LVAD), small enough to be implanted in infants. The design of the impeller and diffuser blades is important for hydrodynamic performance and haemocompatibility of the pump. This study aimed to optimise the blades for pump efficiency using Computational Fluid Dynamics (CFD), machine learning and global optimisation. Meshing of each design typically included 6 million hexahedral elements and a Shear Stress Transport turbulence model was used to close the Reynolds Averaged Navier-Stokes equations. CFD models of 32 base geometries, operating at 8 flow rates between 0.5 and 4 L/min, were created to match experimental studies. These were validated by comparison of the pressure-flow and efficiency-flow curves with those experimentally measured for all base prototype pumps. A surrogate model was required to allow the optimisation routine to conduct an efficient search; a multi-linear regression, Gaussian Process Regression and a Bayesian Regularised Artificial Neural Network predicted the optimisation objective at design points not explicitly simulated. A Genetic Algorithm was used to search for an optimal design. The optimised design offered a 5.51% increase in efficiency at design point (a 20.9% performance increase) as compared to the best performing pump from the 32 base designs. An optimisation method for the blade design of LVADs has been shown to work for a single objective function and future work will consider multi-objective optimisation.

Fluid-structure interaction modelling of a positive-displacement Total Artificial Heart

For those suffering from end-stage biventricular heart failure, and where a heart transplantation is not a viable option, a Total Artificial Heart (TAH) can be used as a bridge to transplant device. The Realheart TAH is a four-chamber artificial heart that uses a positive-displacement pumping technique mimicking the native heart to produce pulsatile flow governed by a pair of bileaflet mechanical heart valves. The aim of this work was to create a method for simulating haemodynamics in positive-displacement blood pumps, using computational fluid dynamics with fluid-structure interaction to eliminate the need for pre-existing in vitro valve motion data, and then use it to investigate the performance of the Realheart TAH across a range of operating conditions. The device was simulated in Ansys Fluent for five cycles at pumping rates of 60, 80, 100 and 120 bpm and at stroke lengths of 19, 21, 23 and 25 mm. The moving components of the device were discretised using an overset meshing approach, a novel blended weak-strong coupling algorithm was used between fluid and structural solvers, and a custom variable time stepping scheme was used to maximise computational efficiency and accuracy. A two-element Windkessel model approximated a physiological pressure response at the outlet. The transient outflow volume flow rate and pressure results were compared against in vitro experiments using a hybrid cardiovascular simulator and showed good agreement, with maximum root mean square errors of 15% and 5% for the flow rates and pressures respectively. Ventricular washout was simulated and showed an increase as cardiac output increased, with a maximum value of 89% after four cycles at 120 bpm 25 mm. Shear stress distribution over time was also measured, showing that no more than [Formula: see text]% of the total volume exceeded 150 Pa at a cardiac output of 7 L/min. This study showed this model to be both accurate and robust across a wide range of operating points, and will enable fast and effective future studies to be undertaken on current and future generations of the Realheart TAH.

Ventricular assist device for end-stage adult congenital heart disease patients: Current status

As long-term surgical outcome of congenital heart disease has continued to improve, most pediatric patients with congenital heart disease are able to reach adulthood. However, adult congenital heart disease (ACHD) patients have increased risk of arrhythmia, valvular diseases, infectious endocarditis, and heart failure. The end-stage ACHD patients with advanced heart failure may require mechanical circulatory support to improve the heart failure symptoms or to recover from circulatory collapse, and may eventually aim to heart transplant or destination therapy. In general, long-term mechanical support for dilated cardiomyopathy or ischemic cardiomyopathy has been achieved with left ventricular assist device with excellent survival outcomes and improved quality of life. However, the ventricular assist device for end-stage ACHD patients can be challenging due to patient-specific anatomical feature, multiple histories of surgical and catheter-based interventions and possible multiple end-organ dysfunctions, and offered less frequently compared to non-ACHD patients. The Interagency Registry for Mechanically Assisted Circulatory Support data published recently showed that ACHD patients receiving long-term mechanical circulatory support consisted <1 % of all registrants and had higher mortality after mechanical support than non-ACHD patients. However, the ACHD patients supported with left ventricular assist device had similar survival with non-ACHD patients and a large proportion of the mortality difference between ACHD and non-ACHD patients seemed to result from operative and perioperative factors. Therefore, the ventricular assist device therapy can be an excellent treatment for selected ACHD patients. In this paper, we describe the current status of ventricular assist device support for end-stage ACHD patients and consideration to the future.

Considerations of valvular heart disease in children with ventricular assist devices

Ventricular assist devices have become a valuable tool in the treatment of heart failure in children. The use of ventricular assist devices has decreased mortality in children with end-stage heart failure awaiting transplant. It is not uncommon for children with end-stage heart failure associated with cardiomyopathy or congenital heart disease to have significant systemic semilunar and atrioventricular valve regurgitation, which can impact the efficiency and efficacy of hemodynamic support provided by a ventricular assist device. Therefore, implanting clinicians should carefully assess for valve abnormalities that may need repair and impact device selection and cannulation strategy to effectively support this diverse population. The purpose of this review is to provide an overview of this important and relevant topic and to discuss strategies for managing these patients.

Zwitterionic coating assisted by dopamine with metal-phenolic networks loaded on titanium with improved biocompatibility and antibacterial property for artificial heart

Introduction: Titanium (Ti) and Ti-based alloy materials are commonly used to develop artificial hearts. To prevent bacterial infections and thrombus in patients with implanted artificial hearts, long-term prophylactic antibiotics and anti-thrombotic drugs are required, and this may lead to health complications. Therefore, the development of optimized antibacterial and antifouling surfaces for Ti-based substrate is especially critical when designing artificial heart implants. Methods: In this study, polydopamine and poly-(sulfobetaine methacrylate) polymers were co-deposited to form a coating on the surface of Ti substrate, a process initiated by Cu²⁺ metal ions. The mechanism for the fabrication of the coating was investigated by coating thickness measurements as well as Ultraviolet-visible and X-ray Photoelectron (XPS) spectroscopy. Characterization of the coating was observed by optical imaging, scanning electron microscope (SEM), XPS, atomic force microscope (AFM), water contact angle and film thickness. In addition, antibacterial property of the coating was tested using Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) as model strains, while the material biocompatibility was assessed by the antiplatelet adhesion test using platelet-rich plasma and in vitro cytotoxicity tests using human umbilical vein endothelial cells and red blood cells. Results and discussion: Optical imaging, SEM, XPS, AFM, water contact angle, and film thickness tests demonstrated that the coating was successfully deposited on the Ti substrate surface. The biocompatibility and antibacterial assays showed that the developed surface holds great potential for improving the antibacterial and antiplatelet adhesion properties of Ti-based heart implants.

An Up-to-Date Literature Review on Ventricular Assist Devices Experience in Pediatric Hearts

Ventricular assist devices (VAD) have gained popularity in the pediatric population during recent years, as more and more children require a heart transplant due to improved palliation methods, allowing congenital heart defect patients and children with cardiomyopathies to live longer. Eventually, these children may require heart transplantation, and ventricular assist devices provide a bridge to transplantation in these cases. The FDA has so far approved two types of device: pulsatile and continuous flow (non-pulsatile), which can be axial and centrifugal. Potential eligible studies were searched in three databases: Medline, Embase, and ScienceDirect. Our endeavor retrieved 16 eligible studies focusing on five ventricular assist devices in children. We critically reviewed ventricular assist devices approved for pediatric use in terms of implant indication, main adverse effects, and outcomes. The main adverse effects associated with these devices have been noted to be thromboembolism, infection, bleeding, and hemolysis. However, utilizing left VAD early on, before end-organ dysfunction and deterioration of heart function, may give the patient enough time to recuperate before considering a more long-term solution for ventricular support.

Lessons Learned from Managing Antithrombotic Therapy in Children Supported with Pediatric Ventricular Assist Devices

Stroke, thromboembolism, and bleeding are the most recognized complications associated with pediatric ventricular assist devices (VADs) and the leading cause of death and disability on VAD support. Recently, newer antithrombotic strategies like bivalirudin have emerged that appear to be associated with a reduction in the neurologic event rates, especially for smaller pediatric-specific VADs like the Berlin Heart and PediMag/CentriMag systems where the risk of stroke is the highest. While contemporary antithrombotic therapies have likely contributed to lowering adverse event rates, we speculate that clotting and bleeding adverse events may have dropped because of a variety of other seemingly small changes to antithrombotic management that are independent of the antithrombotic agents used. This view is supported by recent reports documenting low stroke rates with anticoagulants other than bivalirudin, a drug that may have a wider therapeutic window but is not available in all locations throughout the world. The primary purpose of this report is 1) to summarize contemporary antithrombotic regimens used for smaller pediatric VADs today associated with low event rates in the United States and abroad and () to review 10 practical lessons learned and pitfalls to avoid that we believe to be important to reducing bleeding and clotting events based on our collective experience managing pediatric VADs over the past 20 years irrespective of the antithrombotic agents used.

Waitlist and posttransplant outcomes of critically ill infants awaiting heart transplantation managed without ventricular assist device support

BACKGROUND

Infants listed for heart transplant are at high risk for waitlist mortality. While waitlist mortality for children has decreased in the current era of increased ventricular assist device use, outcomes for small infants supported by ventricular assist device remain suboptimal. We evaluated morbidity and survival in critically ill infants listed for heart transplant and managed without ventricular assist device support.

METHODS

Critically ill infants (requiring ≥1 inotrope and mechanical ventilation or ≥2 inotropes without mechanical ventilation) listed between 2008 and 2019 were included. During the study period, infants were managed primarily medically. Mechanical circulatory support, specifically extracorporeal membrane oxygenation, was utilized as "rescue therapy" for decompensating patients.

RESULTS

Thirty-two infants were listed 1A, 66% with congenital heart disease. Median age and weight at listing were 2.2 months and 4.4 kg, with 69% weighing <5 kg. At listing, 97% were mechanically ventilated, 41% on ≥2 inotropes, and 25% under neuromuscular blockade. Five patients were supported by ECMO after listing. A favorable outcome (transplant or recovery) was observed in 84%. One-year posttransplant survival was 92%. Infection was the most common waitlist complication occurring in 75%. Stroke was rare, occurring in one patient who was supported on ECMO. Renal function improved from listing to transplant, death, or recovery (eGFR 70 vs 87 ml/min/1.73m² , p = .001).

CONCLUSION

A strategy incorporating a high threshold for mechanical circulatory support and acceptance of prolonged mechanical ventilation and neuromuscular blockade can achieve good survival and morbidity outcomes for critically ill infants listed for heart transplant.

Patient and Device Selection in Pediatric MCS: A Review of Current Consensus and Unsettled Questions

The field of pediatric ventricular assist device (VAD) support has expanded significantly over the past 20 years, with one third of pediatric heart transplant recipients currently being bridged to transplant with a VAD. Despite increased pediatric VAD utilization, however, there remains little formalized guidance for patient or device selection. The population of children with advanced heart failure is quite heterogeneous, and the available data suggest that VAD outcomes vary significantly based upon patient size, anatomy, level of illness, and type of device implanted. In an effort to better understand current practice patterns and identify populations for whom there does not appear to be a consensus approach to achieving optimal VAD outcomes, the Advanced Cardiac Therapies Improving Outcomes Network (ACTION) has surveyed clinical decision-making among member sites and conducted a review of the available literature regarding patient population-specific VAD outcomes and center-specific practices related to patient and device selection. Rather than aiming to provide clinical guidelines, this document offers an overview of contemporary approaches to patient and device selection, highlighting specific populations for whom there is not a consensus approach to achieving reliably good VAD outcomes, as these populations may benefit most from future research and quality improvement efforts directed toward identifying best practice.

Children who stroke on VAD support: when is it safe to transplant and what are their outcomes?

OBJECTIVE

Ventricular assist devices (VADs) increase waitlist survival, yet the risk of stroke remains notable. The purpose of this study was to analyze how strokes on VAD support impact post-transplant (post-Tx) outcomes in children.

METHODS

520 pediatric (<18 yo) heart transplant candidates listed from January 2011 to April 2018 with a VAD implant date were matched between the United Network of Organ Sharing and Pediatric Health Information System databases. Patients were divided into pre-Tx Stroke and No Stroke cohorts.

RESULTS

81% of the 520 patients were transplanted. 28% (n=146) had a pre-Tx Stroke. 59% (n=89) of the Stroke patients were transplanted at a median of 57 (IQR 17-102) days from stroke. Significantly more No Stroke cohort (90%) were transplanted (p<0.001). There was no difference in post-Tx survival between the Stroke and No Stroke cohorts (p=0.440). Time between stroke and transplant for patients who died within one year of transplant was 32.0 days (median) compared to 60.5 days for those alive > 1year (p=0.18). Regarding patients in whom time from stroke to transplant was more than 60 days, one-year survival of Stroke vs. No Stroke patients was 96% vs. 95% (p=0.811), respectively.

CONCLUSION

Patients with stroke during VAD support, once transplanted, enjoy similar survival compared to No Stroke patients. We hypothesize that allowing Stroke patients more time to recover could improve post-Tx outcomes. Unfortunately, the ideal duration of time between stroke and safe transplantation could not be determined and will require more detailed and larger studies in the future.

A Mechanistic Lumped Parameter Model of the Berlin Heart EXCOR to Analyze Device Performance and Physiologic Interactions

PURPOSE

The Berlin Heart EXCOR (BH) is the only FDA-approved, extracorporeal pulsatile ventricular assist device (VAD) for infants and children with heart failure. Clinicians control four settings on the device-systolic and diastolic drive pressures, device pump rate, and systolic time as a percentage of the pump cycle. However, interactions between BH pneumatics and the native circulation remain poorly understood. Thus, establishing appropriate device size and settings can be challenging on a patient-to-patient basis.

METHODS

In this study we develop a novel lumped parameter network based on simplified device mechanics. We perform parametric studies to characterize device behavior, study interactions between the left ventricle (LV) and BH across different device settings, and develop patient-specific simulations. We then simulate the impact of changing device parameters for each of three patients.

RESULTS

Increasing systolic pressure and systolic time increased device output. We identified previously unobserved cycle-to-cycle variations in LV-BH interactions that may impact patient health. Patient-specific simulations demonstrated the model's ability to replicate BH performance, captured trends in LV behavior after device implantation, and emphasized the importance of device rate and volume in optimizing BH efficiency.

CONCLUSION

We present a novel, mechanistic model that can be readily adjusted to study a wide range of device settings and clinical scenarios. Physiologic interactions between the BH and the native LV produced large variability in cardiac loading. Our findings showed that operating the BH at a device rate greater than the patient's native heart decreases variability in physiological interactions between the BH and LV, increasing cardiac offloading while maintaining cardiac output. Device rates that are close to the resting heart rate may result in unfavorable cardiac loading conditions. Our work demonstrates the utility of our model to investigate BH performance for patient-specific physiologies.

Early Improvement in Clinical Status Following Ventricular Assist Device Implantation in Children: A Marker for Survival

While clinical status at the time of ventricular assist device (VAD) implant can negatively affect outcomes, it is unclear if early improvement after implant can have a positive effect. Therefore, the objectives of this study were to describe the clinical status of pediatric patients supported with a VAD and determine the impact of clinical status on the 1-month follow-up form on survival and ability to discharge. This was a retrospective analysis of data collected prospectively by the Pediatric Interagency Registry for Mechanical Circulatory Support Registry (Pedimacs) Registry. The Pedimacs database was queried for patients implanted between September 19, 2012, and September 30, 2019, who were alive on VAD support at 1-month postimplant on either a paracorporeal pulsatile or intracorporeal continuous device. Four factors on the 1-month follow-up were the focus of this study: mechanical ventilation, supplemental nutritional support, inotropic support, and ambulatory status. These factors were regarded as present if detected between 1-week and 1-month postimplant and were analyzed to determine their impact on survival following 1 month of VAD support and on successful discharge from hospital in patients with implantable continuous-flow devices. The eligible study cohort consisted of 414 patients with a mean age of 9.6 ± 6.2 years, weight of 40.8 ± 32.3 kg with the majority being male (56.7%) and having cardiomyopathy (68%). An isolated left ventricular assist device (LVAD) was the most common implant (85.5%). At implant, 40% were ventilated, 57% required nutritional support, 93% were on inotropes, and 58% were nonambulating. On the 1-month postimplant form, there were significant improvements in all four categories (14% ventilator support, 46% nutritional support, 53% on inotropes, and 25% nonambulating). However, there was no significant early change in the percentage of patients requiring supplemental nutrition in the paracorporeal pulsatile devices (88% vs. 82%; p = 0.2). Presence of these clinical parameters in early follow-up postimplant had a significant negative impact on survival and on the ability of patients with continuous-flow devices to be discharged. Presence of four specific clinical parameters early after VAD placement is associated with worse overall survival and an inability to discharge patients on VAD support. Ongoing work is needed for optimization of patients before implant and aggressive rehabilitation after implant to help improve long-term outcomes.

Management of circulatory failure after Fontan surgery

With improvement in survival after Fontan surgery resulting in an increasing number of older survivors, there are more patients with a Fontan circulation experiencing circulatory failure each year. Fontan circulatory failure may have a number of underlying etiologies. Once Fontan failure manifests, prognosis is poor, with patient freedom from death or transplant at 10 years of only about 40%. Medical treatments used include traditional heart failure medications such as renin-angiotensin-aldosterone system blockers and beta-blockers, diuretics for symptomatic management, antiarrhythmics for rhythm control, and phosphodiesterase-5 inhibitors to decrease PVR and improve preload. These oral medical therapies are typically not very effective and have little data demonstrating benefit; if there are no surgical or catheter-based interventions to improve the Fontan circulation, patients with severe symptoms often require inotropic medications or mechanical circulatory support. Mechanical circulatory support benefits patients with ventricular dysfunction but may not be as useful in patients with other forms of Fontan failure. Transplant remains the definitive treatment for circulatory failure after Fontan, but patients with a Fontan circulation face many challenges both before and after transplant. There remains significant room and urgent need for improvement in the management and outcomes of patients with circulatory failure after Fontan surgery.

Evolution of Ventricular Assist Device Support Strategy in Children with Univentricular Physiology

BACKGROUND

Since 2012, we have supported 18 children with single ventricle (SV) physiology on ventricular assist devices (VAD) as a bridge to decision, transplant, or recovery. We provide a detailed report of our cumulative surgical experience and lessons learned from these patients.

METHODS

We reviewed all SV-VADs between March 2012 and April 2020. Implanted SV-VADs intended for short-term support were excluded. Demographic and clinical data included palliation stage at the time of VAD implantation, cannulation configuration, device type, duration of support, circuit and device interventions, postoperative support, anticoagulation strategy, complications, mortality, and one-year survival post-discharge.

RESULTS

Five SV-newborns without prior surgical palliation, 8 infants post-Norwood/hybrid procedure, 4 post-Glenn, and 1 post-Fontan were initially supported with either continuous flow13/18(72%) or pulsatile flow 5/18(28%) devices. 3/18(17%) transitioned to another device during support. Before VAD conversion, 9/18(50%) were supported by extracorporeal membrane oxygenation. Outcomes include; 7/18(39%) transplanted, 2/18(11%) recovered, and 9/18(50%) died prior to discharge. Of these deaths, 2 occurred following transplant, 2 following explant and 5 had redirection of care while on support secondary to previously undiagnosed pulmonary veno-occlusive disease (n=2) or severe neurologic events (n=3). Overall, 6/18(33%) experienced neurologic injury. At last follow-up 9/18(50%) children were alive [1.2(0.8-4.3) years post-explant/transplant].

CONCLUSIONS

Our experience shows that SV children, including newborns, can be successfully bridged to desired end-points with proper patient selection and using specific cannulation strategies. Continuing utilization of this strategy is warranted for future children requiring VAD support.

Outcomes From Three Decades of Infant and Pediatric Heart Transplantation

Infants are a unique transplant population due to a suspected immunologic advantage, in addition to differences in size and physiology. Consequently, we expect infants to have significantly different diagnoses, comorbidities, and outcomes than pediatric transplant recipients. In this study, we compare patterns and trends in pediatric and infant heart transplantation during three decades. The United Network for Organ Sharing (UNOS) database was queried for transplants occurring between January 1990 and December 2018. Patients were categorized as pediatric (1-17) or infant (0-1). Congenital heart disease (CHD) primary diagnoses have increased from 37% to 42% in pediatric patients (p = 0.001) and decreased from 80% to 61% in infants during the 1990s and 2010s (p < 0.001). Those with CHD had worse outcomes in both age groups (p < 0.001). Infants who underwent ABO-incompatible transplants had similar survival as compared to those with compatible transplants (p = 0.18). Overall, infants had better long-term survival and long-term graft survival than pediatric patients; however, they had worse short-term survival (p < 0.001). Death due to rejection or graft failure was less likely in infants (p = 0.034). However, death from infection was over twice as common (p < 0.001). In summary, pediatric and infant heart transplant recipients differ in diagnoses, comorbidities, and outcomes, necessitating different care for these populations.

Surgical strategies for the management of end-stage heart failure in infants and children: A 15-year experience with a patient-tailored approach

End‐stage heart failure (ESHF) in pediatric age is an ongoing challenge. Heart transplantation is the final option, but its long‐term outcomes are still suboptimal in children. An alternative patient‐tailored surgical protocol to manage ESHF in children is described. Retrospective, single‐center analysis of pediatric patients admitted to our institution between April 2004 and February 2021 for ESHF. Our current protocol is as follows: (a) Patients <1 year with isolated left ventricular dysfunction due to dilated cardiomyopathy underwent pulmonary artery banding (PAB). (b) Patients <10 years and <20 kg, who did not meet previous criteria were managed with Berlin Heart EXCOR. (c) Patients >10 years or >20 kg, underwent placement of intracorporeal Heartware. Primary outcomes were survival, transplant incidence, and postoperative adverse events. A total of 24 patients (mean age 5.3 ± 5.9 years) underwent 26 procedures: PAB in 6 patients, Berlin Heart in 11, and Heartware in 7. Two patients shifted from PAB to Berlin Heart. Overall survival at 1‐year follow‐up and 5‐year follow‐up was 78.7% (95%CI = 62%‐95.4%) and 74.1% (95%CI = 56.1%‐92.1%), respectively. Berlin Heart was adopted in higher‐risk settings showing inferior outcomes, whereas a PAB enabled 67% of patients to avoid transplantation, with no mortality. An integrated, patient‐tailored surgical strategy, comprehensive of PAB and different types of ventricular assist devices, can provide satisfactory medium‐term results for bridging to transplant or recovery. The early postoperative period is critical and requires strict clinical vigilance. Selected infants can benefit from PAB that has demonstrated to be a safe bridge to recovery.

Paracorporeal Support in Pediatric Patients: The Role of the Patient-Device Interaction

BACKGROUND

Ventricular assist devices (VADs) are important in the treatment of pediatric heart failure. While paracorporeal pulsatile (PP) devices have historically been used, there has been increased use of paracorporeal continuous (PC) devices. We sought to compare the outcomes of children supported with a PP, PC, or combination of devices.

METHODS

Retrospective review (2005-19) of patients <19 years of age from a single center, who received a PC, PP or combination of devices. Patient characteristics were compared between device strategies and Kaplan-Meier survival analysis was performed.

RESULTS

Sixty-six patients were included (62% male, 62% non-congenital heart disease, median age 0.9 years (IQR 0.2, 4.9), median weight 8.5 kg (IQR 4.3, 17.7). PC devices were used in 45% of patients, PP in 35% and a combination in 20%. Patients on PC devices had a lower median weight (p=.02), a higher proportion of CHD (p=.02) and more patients requiring pre-VAD dialysis (p=.01). There was no difference in pre-VAD ECMO (p=.15) use. There was a difference in survival between the three device strategies (p=.02) CONCLUSIONS: Differences in survival was evident, with those on PC support having worse outcomes. Transition from PC to a PP devices was associated with a survival advantage. These findings may be driven by differences in patient characteristics across device strategies. Further studies are required to confirm these findings and to better understand the interaction between patient characteristics and device options.

The evolution of long-term pediatric ventricular assistance devices: a critical review

Introduction: The gap between the number of heart failure patients and the number of potential heart donors has never been larger than today, especially among the pediatric population. The use of mechanical circulatory support is seen as a potential alternative for clinicians to treat more patients. This treatment has proven its efficiency on short-term use. However, in order to replace heart transplant, the techniques should be used over longer periods of time.Areas covered: This review aims at furnishing an engineering vision of the evolution of ventricular assistance devices used in pediatrics. A critical analysis of the clinical complications related to devices generation is made to give an overview of the design improvements made since their inception.Expert opinion: The long-term use of a foreign device in the body is not without consequences, especially among fragile pediatric patients. Moreover, the size of their body parts increases the technical difficulties of such procedure. The balance between the living cells of the body is disturbed by the devices, mostly by the shear stress generated. To provide a safe mechanical circulatory support for long-term use, the devices should be more hemocompatible, preserving blood cells, adapted to the patient's systemic grid and miniaturized for pediatric use.

Clinical course and outcome after treatment with ventricular assist devices in paediatric patients: A single-centre experience

BACKGROUND

Heart failure is a rare condition in the paediatric population, associated with high morbidity and mortality. When medical therapy is no longer sufficient, mechanical circulatory support such as a ventricular assist device can be used to bridge these children to transplant or recovery. Coagulation-related complications such as thrombi, embolism and bleeding events represent the greatest challenge in paediatric patients on mechanical support. We aimed to describe the outcomes and coagulation-related complications in this patient population at our institution.

METHODS

A total of 20 patients with either Berlin Heart EXCOR® or HeartWare® implantation were reviewed in this retrospective study. Study endpoints were survival to heart transplant, weaning due to recovery or death. Thrombotic events were defined as thrombus formation in the device or in the patient, or cardioembolic strokes. Bleeding events were defined as events requiring interventional surgery or transfusion of red blood cells.

RESULTS

The aetiology of heart failure included cardiomyopathy (n = 12), end-stage congenital heart disease (n = 6) and myocarditis (n = 2). Of the 20 patients, 12 were bridged to transplant, 7 recovered and could be weaned and 1 died. The median duration of mechanical support was 84 days (range: 20-524 days). At least one major or minor bleeding event occurred in 45% of the patients. Thrombotic events occurred 21 times in 10 patients. Four of the patients (20%) had no bleeding or thromboembolic event.

CONCLUSION

In all, 95% of the patients were successfully bridged to transplant or recovery. Bleeding events and thrombotic events were common.

The European Registry for Patients with Mechanical Circulatory Support (EUROMACS): second EUROMACS Paediatric (Paedi-EUROMACS) report

OBJECTIVES

A second paediatric report has been generated from the European Registry for Patients with Mechanical Circulatory Support (EUROMACS). The purpose of EUROMACS, which is operated by the European Association for Cardio-Thoracic Surgery, is to gather data related to durable mechanical circulatory support for scientific purposes and to publish reports with respect to the course of mechanical circulatory support therapy. Since the first report issued, efforts to increase compliance and participation have been extended. Additionally, the data provided the opportunity to analyse patients of younger age and lower weight.

METHODS

Participating hospitals contributed pre-, peri- and long-term postoperative data on mechanical circulatory support implants to the registry. Data for all implants in paediatric patients (≤19 years of age) performed from 1 January 2000 to 1 July 2019 were analysed. This report includes updates of patient characteristics, implant frequency, outcome (including mortality rates, transplants and recovery rates) as well as adverse events including neurological dysfunction, device malfunction, major infection and bleeding.

RESULTS

Twenty-nine hospitals contributed 398 registered implants in 353 patients (150 female, 203 male) to the registry. The most frequent aetiology of heart failure was any form of cardiomyopathy (61%), followed by congenital heart disease and myocarditis (16.4% and 16.1%, respectively). Competing outcomes analysis revealed that a total of 80% survived to transplant or recovery or are ongoing; at the 2-year follow-up examination, 20% died while on support. At 12 months, 46.7% received transplants, 8.7% were weaned from their device and 18.5% died. The 3-month adverse events rate was 1.69 per patient-year for device malfunction including pump exchange, 0.48 for major bleeding, 0.64 for major infection and 0.78 for neurological events.

CONCLUSIONS

The overall survival rate was 81.5% at 12 months following ventricular assist device implant. The comparison of survival rates of the early and later eras shows no significant difference. A focus on specific subgroups showed that survival was less in patients of younger age (<1 year of age) (P = 0.01) and lower weight (<20 kg) (P = 0.015). Transplant rates at 6 months continue to be low (33.2%) The fact that the EUROMACS registry is embedded within the European Association for Cardio-Thoracic Surgery Quality Improvement Programme offers opportunities to focus on improving outcomes.

Ventricular Assist Device Therapy in the Fontan Circulation

The number of Fontan patients with circulatory failure and systolic dysfunction is growing rapidly. The last decade has demonstrated that ventricular assist device (VAD) is an effective therapy in properly selected patients. Herein, we discuss the current approach to patient selection, implantation, and patient management.

Diagnosis and Management of Myocarditis: An Evidence-Based Review for the Emergency Medicine Clinician

BACKGROUND

Myocarditis is a potentially fatal condition that can be misdiagnosed in the emergency department (ED) setting.

OBJECTIVE

The purpose of this narrative review article is to provide a summary of the background, pathophysiology, diagnosis, and management of myocarditis, with a focus on emergency clinicians.

DISCUSSION

Myocarditis occurs when inflammation of the heart musculature causes cardiac dysfunction. Symptoms may range from mild to severe and are often preceded by a viral prodrome. Laboratory assessment and an electrocardiogram can be helpful for the diagnosis, but echocardiography is the ideal test in the ED setting. Some patients may also require advanced imaging, though this will often occur during hospitalization or follow-up. Treatment is primarily focused on respiratory and hemodynamic support. Initial hemodynamic management includes vasopressors and inotropes, whereas more severe cases may require an intra-aortic balloon pump, extracorporeal membrane oxygenation, or a ventricular assist device. Nonsteroidal anti-inflammatory drugs should be avoided while intravenous immunoglobulin is controversial.

CONCLUSION

Myocarditis is a serious condition with the potential for significant morbidity and mortality. It is important for clinicians to be aware of the current evidence regarding the diagnosis, management, and disposition of these patients.