Skip to Main Content

INTRODUCTION

Heart failure affects more than 5 million Americans, of whom approximately 6% have advanced heart failure.1,2 Advanced heart failure is characterized by severe progressive symptoms despite optimal medical therapy, recurrent hospital admissions, and very poor prognoses. Therapeutic options include cardiac transplantation, mechanical circulatory support, and palliative care. Cardiac transplantation is limited by donor availability and recipient eligibility.3,4

Left ventricular assist devices (LVADs) provide mechanical circulatory support. They are pumps that move blood from the left ventricle to the aorta. LVADs were first approved in the mid-1990s to support patients as a bridge to transplant (BTT) until a suitable donor heart became available. They have advanced in recent years as a superior alternative to medical therapy in patients who are not eligible for transplantation (i.e., destination therapy [DT]).5 Strict criteria have been established and must be met for a patient to be considered a candidate for a LVAD as DT (Table 47-1).6

TABLE 47-1Indications for an LVAD

The introduction of smaller rotatory, continuous-flow, durable intracorporeal pumps has led to an exponential increase in the number of implants. More than 10,000 continuous-flow LVADs (CF-LVADs) have been implanted in the United States.7,8 The 1-year survival after CF-LVAD implantation for DT has been reported to be approximately 80%.9 The complication rates are high. Within 1 year of implantation, approximately 80% of patients are readmitted for LVAD-associated causes (e.g., device infection, device malfunction, or management of nontherapeutic anticoagulation) and non–LVAD-associated causes (e.g., infections, progressive right ventricular failure, psychosocial issues).10,11 This significant morbidity, along with the increasing number of patients supported by LVADs, requires that Emergency Physicians understand the function and complications of LVADs.12-14

LVAD DEVICES

PUMP FUNDAMENTALS

The LVAD can be conceptualized as a pump that uses energy to move fluid from one site to another (Figures 47-1 and 47-2).15 LVADs have an inflow cannula (i.e., suction pipe) in the left ventricle, a pump, an outflow cannula (i.e., discharge pipe) in the ascending aorta, and a driveline that connects the pump with the system controller. The system controller is connected to a power source (i.e., batteries or direct power). Continuous-flow pumps can be divided into axial and centrifugal. An axial pump uses a propeller in a pipe and transmits rotational energy without a change in the direction of blood. A centrifugal pump uses ...

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.