Pediatric Ventricular Assist Device (Excor) as Bridge to Transplantation
April 15, 2013 | Emerging Technology Reports
ECRI Institute recognizes that many different ventricular assist devices (VADs) have been used or adapted for treating pediatric patients with heart failure (HF), especially very small and very young patients. The Berlin Heart Excor® is the only VAD approved for pediatric patients of any age and size, including neonates. This report focuses on the use of Excor in patients age five years or younger because this population has presented particular challenges regarding the unmet need for a suitably designed VAD that offers a solution when longer-term support is needed than extracorporeal membrane oxygenation can provide.
Proprietary names: Berlin Heart Excor® Pediatric Ventricular Assist Device Generic names: heart pump, pediatric heart pump, pediatric mechanical circulatory support, mechanical circulatory support, ventricular assist device (VAD), left ventricular assist device (LVAD), right ventricular assist device (RVAD), biventricular assist device (BiVAD), extracorporeal pulsatile ventricular assist device, paracorporeal pulsatile ventricular assist device
Pediatric heart failure (HF) is a progressive clinical and pathophysiologic condition in which the heart is unable to pump sufficient blood to meet the body's metabolic needs.1,2 In the United States, the most common cause of pediatric HF is structural congenital heart disease, which can cause volume and/or pressure overload in the ventricles.2,3 In children with structurally normal hearts, the majority of HF cases are caused by cardiac muscle abnormalities (i.e., cardiomyopathies), which impair the heart's ability to pump blood. Other cardiac (e.g., myocarditis, myocardial infarction, acquired valve disorders) and noncardiac (e.g., anemia, sepsis, renal failure) causes also exist.2,4
Clinical presentations of HF may differ among children of different age groups.2 Infants with HF typically exhibit rapid breathing, rapid heartbeat, reduced meal size, difficulty feeding because of shortness of breath, increased fatigue, and failure to thrive.4-6 HF diagnosis in pediatric patients is based on these signs and symptoms, along with noninvasive cardiac imaging (e.g., chest radiograph, echocardiography, cardiac magnetic resonance).3 The New York Heart Association (NYHA) classification system developed to assess HF severity in adults is commonly used to assess pediatric HF severity. The NYHA functional classification system categorizes HF into four classes: asymptomatic (class I), mild (class II), moderate (class III), and severe (class IV). Patients in class III or IV have advanced HF.7 The Interagency Registry for Mechanically Assisted Circulatory Support further subdivides NYHA classes III and IV into patient profiles, including critical cardiogenic shock (profile 1), progressive decline on inotropic support (profile 2), stable but inotrope dependent (profile 3), resting symptoms home on oral therapy (profile 4), and a continuum of class IV patients with restricted activity and with little fluid overload (profiles 5, 6, and 7).8 Despite wide use of the NYHA classification system, critics argue that it does not accurately assess HF in pediatric patients because of differences in HF presentation and difficulty applying activity-related measures to infants and children, but the NYHA can be used in older children and adolescents.2 Pediatric-specific assessments, which would be better suited for younger patients, include the Ross classification system and New York University Pediatric HF Index; however, neither measure has been validated.2 The Ross classification system grades infant HF severity based on historical variables and examination findings (i.e., meal size, feeding time, respiratory rate, respiratory pattern, heart rate, peripheral perfusion, presence of diastolic filling sounds, degree of liver enlargement).9 Ross rating score categories include no, mild, moderate, or severe HF.9 The New York University Pediatric HF Index grades HF in children based on physical signs and symptoms and prescription drug therapy.6 Scores in this index range from 0, which represents no HF, to 30, which represents severe HF.6