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).

Rivaroxaban versus standard anticoagulation for acute venous thromboembolism in childhood. Design of the EINSTEIN-Jr phase III study.

BACKGROUND: Venous thromboembolism (VTE) is a relatively rare condition in childhood with treatment mainly based on extrapolation from studies in adults. Therefore, clinical trials of anticoagulation in children require novel approaches to deal with numerous challenges. The EINSTEIN-Jr program identified pediatric rivaroxaban regimens commencing with in vitro dose finding studies followed by evaluation of children of different ages through phase I and II studies using extensive modeling to determine bodyweight-related doses. Use of this approach resulted in drug exposure similar to that observed in young adults treated with rivaroxaban 20 mg once-daily. METHODS: EINSTEIN-Jr phase III is a randomized, open-label, study comparing the efficacy and safety of rivaroxaban 20 mg-equivalent dose regimens with those of standard anticoagulation for the treatment of any types of acute VTE in children aged 0-18 years.A total of approximately 500 children are expected to be included during the 4-year study window. Flexibility of treatment duration is allowed with study treatment to be given for 3 months with the option to continue treatment in 3-month increments, up to a total of 12 months. However, based on most common current practice, children younger than 2 years with catheter-related thrombosis will have a main treatment period of 1 month with the option to prolong treatment in 1-month increments, up to a total of 3 months. CONCLUSIONS: EINSTEIN-Jr will compare previously established 20 mg-equivalent rivaroxaban dosing regimens with standard anticoagulation for the treatment of VTE in children. Demonstration of similarity of disease, as well as equivalent rivaroxaban exposure and exposure-response will enable extrapolation of efficacy from adult trials, which is critical given the challenges of enrollment in pediatric anticoagulation trials. TRIAL REGISTRATION: Clinicaltrials.gov NCT02234843, registered on 9 September 2014.

Evaluation of enoxaparin dosing requirements in infants and children. Better dosing to achieve therapeutic levels.

Increasing the starting dose of enoxaparin results in the early achievement of therapeutic anti-factor Xa levels in children receiving enoxaparin which is critical for effective therapy and the reduction of venipunctures. The aim of this study was: i) to determine the enoxaparin dose required to achieve therapeutic anti-factor Xa levels in infants and children, and ii) to establish whether increasing the starting dose of enoxaparin influenced the time required to reach the therapeutic range and the number of venipunctures required for dose-adjustment, and iii) the radiographic outcome of the thrombosis, where applicable. A retrospective chart review of children who received enoxaparin was carried out at the Stollery Children's Hospital, Edmonton, Alberta, Canada. Patients treated with standard-dose enoxaparin (1.5 mg/kg for children < or =3 months of age, 1.0 mg/kg for children > or =3 months of age), were compared with children who received a higher initial starting dose of enoxaparin (1.7 mg/kg for children > or =3 months of age, 1.2 mg/kg for children > or =3 months of age). Infants <3 months required an enoxaparin dose of 1.83 mg/kg, and those who received an increased initial enoxaparin dose resulted in faster attainment of therapeutic anti-factor Xa levels requiring significantly fewer venipunctures. Similarly, infants > or =3-12 months, 1-5 years, and 6-18 years, require enoxaparin 1.48 mg/kg, 1.23 mg/kg and 1.13 mg/kg, respectively, in order to achieve a therapeutic anti-factor Xa level. In conclusion, increasing the starting dose of enoxaparin may result in more rapid attainment of therapeutic range with fewer venipunctures, dose adjustments, and without an increase in adverse events.