Use of Intracorporeal Durable LVAD Support in Children Using HVAD or HeartMate 3-A EUROMACS Analysis

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: <0.000) and had lower BSA values (1.3 vs. 1.6 m2, p: <0.000). Median support time was 204 days. Overall, 98 patients (69%) were discharged and sent home, while 87% were discharged in group HM3 (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.

Outcomes in small children on Berlin Heart EXCOR support: age and body surface area as clinical predictive factors

OBJECTIVES

The Berlin Heart EXCOR (BHE) offers circulatory support across all paediatric ages. Clinically, the necessary care and the outcomes differ in various age groups. The EUROMACS database was used to study age- and size-related outcomes for this specific device.

METHODS

All patients <19 years of age from the EUROMACS database supported with a BHE between 2000 and November 2021 were included. Maximally selected rank statistics were used to determine body surface area (BSA) cut-off values. Multivariable Cox proportional hazard regression using ridge penalization was performed to identify factors associated with outcomes.

RESULTS

In total, 303 patients were included [mean age: 2.0 years (interquartile range: 0.6-8.0, males: 48.5%)]. Age and BSA were not significantly associated with mortality (n = 74, P = 0.684, P = 0.679). Factors associated with a transplant (n = 175) were age (hazard ratio 1.07, P = 0.006) and aetiology other than congenital heart disease (hazard ratio 1.46, P = 0.020). Recovery rates (n = 42) were highest in patients with a BSA of <0.53 m2 (21.8% vs 4.3-7.6% at 1 year, P = 0.00534). Patients with a BSA of ≥0.73 m2 had a lower risk of early pump thrombosis but a higher risk of early bleeding compared to children with a BSA of <0.73 m2.

CONCLUSIONS

Mortality rates in Berlin Heart-supported patients cannot be predicted by age or BSA. Recovery rates are remarkably high in the smallest patient category (BSA <0.53 m2). This underscores that the BHE is a viable therapeutic option, even for the smallest and youngest patients.

Cerebrovascular accidents in paediatric patients supported by the Berlin Heart EXCOR

OBJECTIVES

Ventricular assist device support as a bridge to transplant or recovery is a well-established therapy in children on the cardiac transplant waiting list. The goal of this study was to investigate the incidence of and the associated factors for cerebrovascular accidents in paediatric patients supported by a Berlin Heart EXCOR.

METHODS

All patients <19 years of age supported by a Berlin Heart EXCOR between January 2011 and January 2021 from the European Registry for Patients with Mechanical Circulatory Support were included.

RESULTS

In total, 230 patients were included. A total of 140 (60.9%) patients had a diagnosis of dilated cardiomyopathy. 46 patients (20.0%) sustained 55 cerebrovascular accidents, with 70.9% of the episodes within 90 days after the ventricular assist device was implanted. The event rate of cerebrovascular accidents was highest in the first era (0.75). Pump thrombosis and secondary need for a right ventricular assist device were found to be associated with a cerebrovascular accident (hazard ratio 1.998, P = 0.040; hazard ratio 11.300, P = 0.037). At the 1-year follow-up, 44.4% of the patients had received a transplant, 13.1% were weaned after recovery and 24.5% had died. Event rates for mortality showed a significantly decreasing trend.

CONCLUSIONS

Paediatric ventricular assist device support is associated with important adverse events, especially in the early phase after the device is implanted. Pump thrombosis and the need for a secondary right ventricular assist device are associated with cerebrovascular accidents. Furthermore, an encouragingly high rate of recovery in this patient population was shown, and death rates declined. More complete input of data into the registry, especially concerning anticoagulation protocols, would improve the data.

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.

Current perspectives on mechanical circulatory support

Mechanical circulatory support gained a significant value in the armamentarium of heart failure therapy because of the increased awareness of the prevalence of heart failure and the tremendous advances in the field of mechanical circulatory support during the last decades. Current device technologies already complement a heart transplant as the gold standard of treatment for patients with end-stage heart failure refractory to conservative medical therapy. This article reviews important aspects of mechanical circulatory support therapy and focuses on currently debated issues.

Utilization and Outcomes of Children Treated with Direct Thrombin Inhibitors on Paracorporeal Ventricular Assist Device Support

Thrombotic and bleeding complications have historically been major causes of morbidity and mortality in pediatric ventricular assist device (VAD) support. Standard anticoagulation with unfractionated heparin is fraught with problems related to its heterogeneous biochemical composition and unpredictable pharmacokinetics. We sought to describe the utilization and outcomes in children with paracorporeal VAD support who are treated with direct thrombin inhibitors (DTIs) antithrombosis therapy. Retrospective multicenter review of all pediatric patients (aged <19 years) treated with a DTI (bivalirudin or argatroban) on paracorporeal VAD support, examining bleeding and thrombotic adverse events. From May 2012 to 2018, 43 children (21 females) at 10 centers in North America, median age 9.5 months (0.1-215 months) weighing 8.6 kg (2.8-150 kg), were implanted with paracorporeal VADs and treated with a DTI. Diagnoses included cardiomyopathy 40% (n = 17), congenital heart disease 37% (n = 16; single ventricle n = 5), graft vasculopathy 9% (n = 4), and other 14% (n = 6). First device implanted included Berlin Heart EXCOR 49% (n = 21), paracorporeal continuous flow device 44% (n = 19), and combination of devices in 7% (n = 3). Adverse events on DTI therapy included; major bleeding in 16% (n = 7) (2.6 events per 1,000 patient days of support on DTI), and stroke 12% (n = 5) (1.7 events per 1,000 patient days of support on DTI). Overall survival to transplantation (n = 30) or explantation (n = 8) was 88%. This is the largest multicenter experience of DTI use for anticoagulation therapy in pediatric VAD support. Outcomes are encouraging with lower major bleeding and stroke event rate than that reported in literature using other anticoagulation agents in pediatric VAD support.

Permanent Implantable Cardiac Support Systems

BACKGROUND

Nearly 1000 permanent ventricular assist devices (VADs) are implanted in patients with severe congestive heart failure in Germany each year. VADs are miniaturized centrifugal pumps that generate continuous blood flow; they are powered and controlled through a cable that passes through the skin. Para- corporeal systems are only rarely implanted, usually in children.

METHODS

In this selective review of the literature, including guidelines and registry data, we discuss the indications, therapeutic effects, and complications of permanently implantable cardiac support systems.

RESULTS

The optimal time for VAD implantation cannot be precisely defined. A comparative assessment of the various available systems is not possible, as no randomized trials have been performed on this topic. Registry data indicate that 69% to 81% of patients survive one year after VAD implantation, which is signifi- cantly better than the natural course of (conservatively treated) severe congestive heart failure. The distance patients are able to walk is 129 to 220 m longer at six months, depending on the system implanted. Scores on the EQ-5D health status questionnaire are 28 to 37 points better at six months. The potential severe compli- cations include infection, right-heart failure, hemorrhage, pump thrombosis, stroke, and death.

CONCLUSION

A VAD system can be implanted as an alternative to cardiac transplan- tation or as a bridging treatment until the patient can be listed for transplantation and receive the transplant. Because of the organ s , only a minority of VAD patients ever receive a transplant.

"The heart supporters": systematic review for ventricle assist devices in congenital heart surgery

Ventricular assist device (VAD) implantation is a widely used procedure in children with cardiac failure refractory to medical therapy as a long-term bridge to recovery or transplant. This strategy has proved to be of an enormous advantage in the cure of these children. The aim of this review is to evaluate the current strategies used for clinical monitoring of paediatric patients with a VAD, focusing on the management of several aspects such as anticoagulant and antiplatelet therapy, haemorrhagic and thrombotic complications, as well as the effects that VADs have on the exposure, effectiveness and the safety of drugs. The sources used for this research are MEDLINE, PubMed and Cochrane Library. The use of key words such as "paediatric ventricular assist device", "clinical management", "anticoagulant therapy" and "infections" retrieved 146 papers. With the application of the inclusion criteria, 42 articles have been selected, but following further analysis, only 21 were eligible. The post-implant process is still complicated due to the lack of guidelines regarding clinical management and for the frequent occurrence of adverse events including bleeding, infection and thromboembolic episodes. From these findings, we can highlight the importance of establishing a suitable antithrombotic therapy, as well as ensuring that the prevention and treatment of infection are paramount during the management of these patients. The clinical management of VAD paediatric children is complex and challenging. At the moment, there are no guidelines regarding strategies to adopt, but from the analysed surveys, it has been possible to highlight a relative coherence between adopted therapies in different centres worldwide.

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

OBJECTIVES:

EUROMACS is a registry of the European Association for Cardio-Thoracic Surgery (EACTS) whose purpose is to gather clinical data related to durable mechanical circulatory support for scientific purposes and to publish annual reports. Because the treatment of children with end-stage heart failure has several significantly different characteristics than the treatment of adults, data and outcomes of interventions are analysed in this dedicated paediatric report.

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 31 December 2017 were analysed. This report includes updates of patient characteristics, implant frequency, outcome (including mortality rates, transplants and recovery rates) as well as adverse events.

RESULTS:

Twenty-five hospitals contributed 237 registered implants in 210 patients (81 ♀, 129 ♂) to the registry. The most frequent diagnosis was any form of cardiomyopathy (71.4%) followed by congenital heart disease (18.6%). Overall mean support time on a device was 11.6 months (±16.5 standard deviation). A total of 173 children (82.4%) survived to transplant, recovery or are ongoing; 37 patients (17.6%) died while on support within the observed follow-up time. At 12 months 38% of patients received transplants, 7% were weaned from their device and 15% died. At 24 months, 51% of patients received transplants, 17% died while on support, 22% were on a device and 9% were explanted due to myocardial recovery. The adverse events rate per 100 patient-months was 11.97 for device malfunction, 2.83 for major bleeding, 2.83 for major infection and 1.52 for neurological events within the first 3 months after implantation.

CONCLUSIONS:

The first paediatric EUROMACS report reveals a low transplant rate in European countries within the first 2 years of implantation compared to US data. The 1-year survival rate seems to be satisfactory. Device malfunction including pump chamber changes due to thrombosis was the most frequent adverse event.