Use of Mechanical Circulatory Support Devices in End-Stage Heart Failure Patients

Role of acute mechanical circulatory support devices in cardiogenic shock

Cardiogenic shock is a state of low cardiac output that is associated with significant morbidity and mortality. A considerable proportion of patients with cardiogenic shock respond poorly to medical management and require acute mechanical circulatory support (AMCS) devices to improve tissue perfusion as well as to support the heart. In the last two decades, many new AMCS devices have been introduced to support the right, left, and both ventricles. All these devices vary in terms of the support they provide to the body and heart, mechanism of functioning, method of insertion, and adverse events. In this review, we compare and contrast the available percutaneous and surgically placed AMCS devices used in cardiogenic shock and discuss the associated clinical and hemodynamic data to make a conscious decision about choosing a device.

Heart Transplantation After Ventricular Assist Device Therapy: Benefits, Risks, and Outcomes

Heart transplantation is an established treatment for end-stage heart failure. Due to the increase in demand and persistent scarcity of organ, mechanical circulatory devices have played a major role in therapy for advanced heart failure. Usage of left ventricular assist device (LVAD) has gone up from 6% in 2006 to 43% in 2013 as per the United Network of Organ Sharing database. Majority of patients presenting for a heart transplantation are often bridged with an assist device prior for management of heart failure while on wait-list. On one hand, it is well established that LVADs improve survival on wait-list; on the other hand, the effect of LVAD on morbidity and survival after a heart transplantation is still unclear. In this article, we review the available literature and attempt to infer the outcomes given the risks and benefits of heart transplantation with prior LVAD patients.

Rotary mechanical circulatory support systems

A detailed survey of the current trends and recent advances in rotary mechanical circulatory support systems is presented in this paper. Rather than clinical reports, the focus is on technological aspects of these rehabilitating devices as a reference for engineers and biomedical researchers. Existing trends in flow regimes, flow control, and bearing mechanisms are summarized. System specifications and applications of the most prominent continuous-flow ventricular assistive devices are provided. Based on the flow regime, pumps are categorized as axial flow, centrifugal flow, and mixed flow. Unique characteristics of each system are unveiled through an examination of the structure, bearing mechanism, impeller design, flow rate, and biocompatibility. A discussion on the current limitations is provided to invite more studies and further improvements.