American Journal of Transplantation 2015; 15: 453–460 Wiley Periodicals Inc.
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Copyright 2015 The American Society of Transplantation and the American Society of Transplant Surgeons doi: 10.1111/ajt.13003
Outpatient Management of Intra-Corporeal Left Ventricular Assist Device System in Children: A Multi-Center Experience y
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M. Schweiger1,*, , C. Vanderpluym2, , A. Jeewa3, C. E. Canter4, P. Jansz5, P. E. Parrino6, O. Miera7, J. Schmitto8, M. Mehegan4, I. Adachi3, M. Hu¨bler1 and D. Zimpfer9 1
Department of Congenital Cardiovascular Surgery, Children’s Hospital Zurich, Zurich, Switzerland 2 Boston Children’s Hospital, Boston, MA 3 Texas Children’s Hospital, Houston, TX 4 St. Louis Children’s Hospital, St. Louis, MO 5 St Vincent’s Hospital, Sydney, Australia 6 Ochsner Medical Center, New Orleans, LA 7 German Heart Institute, Berlin, Germany 8 Department of Cardio-, Thoracic-, Transplantation-, and Vascular Surgery, Hannover Medical School, Hannover, Germany 9 Department for Cardiac Surgery, Medical University Vienna, Vienna, Austria Corresponding author: Martin Schweiger,
[email protected] y Both authors contributed equally. Little is known about the outcomes of children supported on intracorporeal left ventricular assist device (HVAD), and the feasibility of outpatient management. All centers with pediatric patients discharged from the hospital on the device were identified using company database. A total of 14 centers were contacted, with 9 centers, contributing data retrospectively. From 2011 to 2013, 12 pediatric patients (7 females), mean aged 11.9 2.3 years (range 8–15), mean weight 43 19 kg (range 18–81), mean body surface area 1.3 0.3 m2 (range 0.76–1.96) were identified. Diagnosis included: dilated cardiomyopathy (CMP) (n ¼ 5), noncompaction CMP (n ¼ 4), toxic CMP (n ¼ 2) and viral CMP (n ¼ 1). Indications for support were permanent support (n ¼ 1), bridge to recovery (n ¼ 1) and bridge to transplantation (n ¼ 10). Prior to HVAD implantation, all patients received intravenous inotropes and two patients were on temporary mechanical support. Overall mortality was 0%. Mean duration of inpatient and outpatient support were 56 (range: 19–95 days) and 290 days (range: 42–790), respectively. Mean readmission rate was 0.02 per patient month (2.1 per patient). No adverse events involving emergency department occurred. Eight children resumed local schooling. Home discharge of children supported on HVAD is feasible and safe.
School integration can be achieved. There is wide center variability to discharge practice for children. Abbreviations: CMP, cardiomyopathy; ECLS, extracorporeal life support; ECMO, extracorporeal membrane oxygenation; EMS, emergency medical service; HTx, heart transplantation; HVAD, heartware ventricular assist device; LVAD, left ventricular assist device; MCS, mechanical circulatory support; N, number; PRA, panel reactive antibodies; VAD, ventricular assist device Received 13 June 2014, revised 04 August 2014 and accepted for publication 02 September 2014
Introduction The use of mechanical circulatory support (MCS) in children has evolved dramatically over the last 20 years. Extracorporeal membrane oxygenation (ECMO) has been the primary circulatory support strategy in children, due to its suitability for patients of all sizes, widespread availability and ease of implantation. However, ECMO support has been limited by life-threatening complications; namely, infection, bleeding and thromboembolism that accrue over days to weeks. As such, there has been growing momentum in the use of ‘‘durable’’ long term MCS for children in the form of ventricular assist devices (VAD). To date, the Berlin Heart EXCOR1 has been mainstay of long term VAD support for children. While the Berlin Heart is vastly superior to ECMO in terms of survival to transplantation, the device is far from perfect due its unacceptably high risk of thromboembolic events and paracorporeal design that precludes discharge from hospital (1,2). The armamentarium of VAD options for adults has expanded drastically over the last decade, with a shift from extracorporeal (externalized pumps) to intracorporeal (internalized pump) device design. The pediatric population has benefited greatly by the surge in device development, with increased miniaturization of device design allowing for implantation in smaller patients (1,3,4). One such device, the HeartWare1 HVAD system (Framingham, MA), is an intracorporeal centrifugal continuous flow VAD that is implanted directly into the left ventricular apex and remains housed within the pericardial space (5,6). There is 453
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expanding use of the HeartWare device in children and adolescent patients (7,8). Similar to adult patients, these children can be discharged home and resume regular activities of daily living. However, to date little is known about the outcomes of children supported on HeartWare1 VAD and the feasibility of outpatient management. We sought to describe the strategies to achieve outpatient management and outcomes for children supported with the HeartWare1 VAD (HVAD).
Methods Study population Using the HeartWare1 Inc., database, all centers that had discharged pediatric patients with the HeartWare1 HVAD system between 2011 and 2013 were contacted. Of the 14 centers identified, 9 (4 USA, 1 Australia, 4 Europe) agreed to participate and contribute data retrospectively. Out of the 5 centers not participating 2 answered but never provided data and 3 never provided data. Inclusion criteria for the study cohort included: patient 18 years at time of implantation who had been discharged from hospital and managed as outpatients.
HVAD systems out of a total of 20 (60%) patients who underwent HVAD implantation at the participating nine centers worldwide. Reason for not discharge patients home were transplanted prior to discharge (n:4), not familiar with outpatient management (n:2), social reasons (n:2). Only patients discharged home were included in the study. Patient characteristics at time of HVAD implantation are presented in Table 1. Of the 12 patients forming the study cohort, all were on intravenous inotropes prior to HVAD implantation, and 2 patients were supported on temporary MCS (ECMO, n ¼ 1; intra-aortic balloon pump, n ¼ 1). Underlying diagnosis included: dilated cardiomyopathy (n ¼ 5), noncompaction cardiomyopathy (n ¼ 4), chemotoxicity induced cardiomyopathy (n ¼ 2), viral myocarditis (n ¼ 1). Indications for LVAD placement were bridge to decision (n ¼ 1) and bridge to transplant (n ¼ 11). All implants were performed with cardiopulmonary bypass and four additional procedures were completed in three patients (tricuspid valve annuloplasty [n ¼ 1], patent foramen ovale closure [n ¼ 1], aortic valve reconstruction [n ¼ 1] and right atrial thrombus removal [n ¼ 1]). However, after a period of rehabilitation one patient and family decided they
Study design and definitions The primary study hypothesis is that outpatient management of pediatric patients with HVAD system is feasible; with low rate of readmission, adverse events and mortality. We sought to describe the baseline characteristics and outcomes of pediatric patients with HVAD system who were discharged home. Demographic and clinical variables were defined at the time of HVAD implantation and at time of discharge. PostHVAD implant variables include: presence of right heat failure, duration of inpatient and outpatient support, number and reason for readmission, number of adverse events and survival to transplantation. Right heart failure was defined as the need for MCS in the form of ECMO or placement of right VAD. Antithrombotic practices, as defined by the use of anticoagulation and antiplatelet therapies, were described across centers. Participating centers were surveyed regarding outpatient training strategies; including training of emergency response services (EMS), primary care provider/pediatrician and school staff. We received approval from each participating center’s institutional review board. All data were collected retrospectively from written and electronic medical records. Participating centers were also surveyed regarding; training methods for home discharge, frequency of outpatient visits and outpatient anticoagulation management.
Statistical analysis Summary data are presented as median (25th, 75th percentile), mean (standard deviation) (SD) or number (percent). Data were analyzed using statistical software SPSS software (version 15.0; SPSS, Inc., Chicago, IL). All statistical tests were two-sided and a p-value
