Mechanical circulatory support devices: methods to optimize hemodynamics during use

INTRODUCTION: Mechanical circulatory support (MCS) is an increasingly utilized mode of therapy in the management of advanced heart failure, both as bridge to heart transplantation and destination therapy. As MCS becomes more prevalent, it is ever more important to understand the complex hemodynamics of these devices, as well as the strategies for hemodynamic optimization. Areas covered: This review provides an overview of hemodynamics in the normal human heart and the failing heart. We discuss the various short-term mechanical circulatory support devices and their hemodynamic consequences. We will then discuss the differences between left ventricular assist devices, and the impact of these differences on hemodynamics. We will describe the strategies for hemodynamic optimization using echocardiographic and invasive ramp studies. Finally, we will discuss the impact of speed changes with exercise and discuss future directions for advancements in MCS therapies. Expert commentary: We advocate for a deeper understanding of the hemodynamics underpinning MCS devices. We also recommend the more widespread use of ramp studies for speed optimization, which have been well validated across a number of different left ventricular assist device types.