Implantable Mechanical Circulatory Support: Demystifying Patients With Ventricular Assist Devices and Artificial Hearts

Abstract

Engineering advancements have expanded the role for mechanical circulatory support devices in the patient with heart failure. More patients with mechanical circulatory support are being discharged from the implanting institution and will be seen by clinicians outside the immediate surgical or heart-failure team. This review provides a practical understanding of device design and physiology, general troubleshooting, and limitations and complications for implantable left ventricular assist devices (pulsatile-flow and continuous-flow pumps) and the total artificial heart.

ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure 2012

“…MCS is an umbrella term describing a number of different technologies used to provide both short‐ and longer term assistance in patients with either chronic HF or AHF. A variety of terms have been used to describe the use of these technologies ( Table ) ,. The most experience is with MCS in end‐stage HF, initially as bridge to transplantation (BTT), but more recently as destination therapy (DT).…”

“…Typically, patients with end‐stage HF considered for MCS are on continuous inotropic support ( Table ) ,,. Evaluation of right ventricular function is crucial as post‐operative right ventricular failure greatly increases perioperative mortality and reduces survival to, and after, transplantation.…”

Hemolysis from Aortic Regurgitation Mimicking Pump Thrombosis in a Patient with a HeartMate II Left Ventricular Assist Device

“…5,6 A combination of power spikes and evidence of intravascular hemolysis caused high suspicion for a pump thrombus in contact with the rotor. 3 However, the absence of heart failure, maintenance of device speed, hypertension, and proper unloading of the LV were against this diagnosis. Cyclical acute power spikes may suggest passage of extraneous thrombus, from the left atrium, ventricle, or aortic root, if AR is present.…”

“…The current opinion for troubleshooting complications of LVAD therapy suggests that pump thrombosis should be strongly considered if there is fluctuating power and evidence of intravascular hemolysis. 3,4 A case is presented where a combination of an elevated mean arterial pressure (MAP) and the development of aortic regurgitation (AR) mimicked a device thrombus in a patient with a HeartMate II (HM II; Thoratec Corporation, Pleasanton, CA) LVAD implanted for destination therapy.…”

Rotary mechanical circulatory support systems

“…The spinning rotor draws blood into the pumping chamber along the rotor's axis and propels it tangentially through an outflow graft aligned perpendicular to the inflow cannula. 51 Motor drive and magnetic levitation coils share the same stator. Thus, no separate motor or bearing exists.…”