Pediatric Mechanical Circulatory Support

Talking with caregivers of children living in the community with ventricular assist devices

A VAD is a mechanical pump used to support the functioning of a failing heart. As a pediatric therapy, a VAD is used as a temporary solution for poor heart function, a bridge to transplantation or recovery, or a destination therapy. The goal of this qualitative study was to explore the perspectives of family and professional caregivers of children who are supported by VADs in outpatient settings. Semi-structured interviews were conducted with 22 caregivers of school-aged children discharged home on VAD support. Interviews were transcribed, and data were analyzed using qualitative content analysis. Caregivers identified issues facing children on VAD support in the contexts of home, school, and other childhood places including being physically connected to a device; experiencing changes; living a medical life; negotiating restrictions; cost of care; family, kinship, and community; and, present and future living. While a child with a VAD may have much in common with other medically complex children, the technological complications and risks of living with a VAD are uniquely identified by caregivers as an issue, especially when considering the way that children with a VAD are connected to their device-implanted yet exterior, mobile yet restricted, and autonomous yet dependent.

The Ventricular Assist Device in the Life of the Child: A Phenomenological Pediatric Study

What is it like for a child to live with an artificial heart? The use of some medical therapies in children requires developmental considerations, is associated with psychosocial consequences, and calls for ethical sensitivities. A critical case is the ventricular assist device (VAD), a mechanical pump used to support the functioning of a failing heart. As a pediatric therapy, the device can be used as a temporary solution for poor heart function, a bridge to transplantation or recovery, or as a destination therapy. While the mechanical-technical operation of the VAD is well understood, the clinical-technical aspects of young people living with this device are largely unexplored. Drawing on interviews of school-aged children, the aim of this phenomenological study is to explore how a VAD may structure or condition a child's meaningful experience of their world outside the hospital. The driveline of an implanted VAD is the peripheral attachment, extruding through the skin to connect the controller-power supply. The materiality of the device may be interruptive, restrictive, and disturbing to the psycho-physical being and sense of self-identity of the child as a child. And while a child equipped with a VAD is not necessarily conspicuous among other children, the child may experience the device as an exposing presence, while living with the worry of a caregiver who takes on the role not simply of parent but of watchful health professional. A phenomenological understanding of the VAD should assist parents and caregiving health professionals knowing how to deal with specific issues arising in the life of the VAD child.

Recent advances in computational methodology for simulation of mechanical circulatory assist devices

Ventricular assist devices (VADs) provide mechanical circulatory support to offload the work of one or both ventricles during heart failure. They are used in the clinical setting as destination therapy, as bridge to transplant, or more recently as bridge to recovery to allow for myocardial remodeling. Recent developments in computational simulation allow for detailed assessment of VAD hemodynamics for device design and optimization for both children and adults. Here, we provide a focused review of the recent literature on finite element methods and optimization for VAD simulations. As VAD designs typically fall into two categories, pulsatile and continuous flow devices, we separately address computational challenges of both types of designs, and the interaction with the circulatory system with three representative case studies. In particular, we focus on recent advancements in finite element methodology that have increased the fidelity of VAD simulations. We outline key challenges, which extend to the incorporation of biological response such as thrombosis and hemolysis, as well as shape optimization methods and challenges in computational methodology.

Perioperative mechanical circulatory support in children with critical heart disease

OPINION STATEMENT

The treatment of cardiovascular failure in the perioperative period with the use of mechanical circulatory support is a well-recognized, well-developed, and commonly utilized treatment modality. Regardless of the exact circumstances of initiation, the use of a support device is a "bridge." Where there has been an acute myocardial insult, short-term assist devices can serve as a "bridge to immediate survival," a "bridge to recovery," or even a "bridge to the next decision." Mechanical circulatory support can serve as a treatment of cardiovascular decompensation caused by myocarditis, acute myocardial insult, low cardiac output following surgery, and congenital heart disease. The utilization of such support carries significant risks such as bleeding, infection, and thrombosis. However, these can be minimized in order to allow for the safe and effective deployment of this therapeutic strategy. One specific therapeutic domain in which these devices provide immediate impact is during cardiac arrest. Although outcomes of cardiac arrest remain poor, use of a mechanical device as an intervention has allowed salvage of otherwise certain mortality. However, it is important to note that the utility of support was most pronounced in patients that were not on either extreme of the survival prediction curve. This can be best summarized by the concept of "not too early, not too late." Therefore, it is the responsibility of the entire care team to find the appropriate patient population in which to "pull the trigger" on mechanical support as a therapy. This decision point is supported by a monitoring strategy that can be utilized to predict deterioration and intervene adequately. Most importantly, an effective monitoring strategy allows the practitioner to judge the effectiveness of treatment and support strategies and make adjustments in a timely manner, potentially with mechanical support in the perioperative period.

Ventricular assist device placement in an adult with D-transposition of the great arteries with prior Mustard operation

Adults with congenital heart defects and congestive heart failure are a challenging population because of their complex anatomy, prior surgical palliation, and hemodynamic status. We report one of the first cases of a ventricular assist device placement in a patient with decompensated heart failure and a history of D-transposition of the great vessels who had a prior atrial switch operation.

Mechanical circulatory support for the pediatric patient

In adult patients, mechanical circulatory support (MCS) devices are part of the standard of care for heart failure. There are several options available that clinicians may use to provide support for their patients and thus the choice of devices can be tailored to their individual needs. Unfortunately, this is not the case for pediatric patients with heart failure, where the options for MCS modalities are far more limited because of size constraints and regulatory hurdles. Furthermore, the pathophysiology of heart failure in children is not identical to that of adults; thus, the device selection and configuration require different considerations. Management of pediatric patients on MCS requires a highly specialized team of pediatric professionals. The nurse caring for a child on MCS is an active participant in all aspects of the patient's care and must have an in-depth understanding of the patient's underlying physiology, the circulatory physiology of the MCS system, the reason for mechanical support, and the goal of support.