Imaging for Ventricular Function and Myocardial Recovery on Nonpulsatile Ventricular Assist Devices

Advances in the field of device support have led to increased use of continuous-flow left ventricular assist devices (LVADs) to improve outcomes in patients with end-stage heart disease. Newer-generation LVADs have become the pump of choice for bridging to heart transplantation and as destination therapy for patients with contraindications to transplantation.1 Different imaging modalities have played a major role in LVAD preoperative, early postoperative, and long-term follow-up management. The primary imaging modality to monitor patients with continuous-flow LVADs is echocardiography. The present review highlights the role of echocardiography and the other imaging modalities in the assessment of ventricular size and function, intracardiac hemodynamics, and myocardial recovery of patients with continuous-flow LVADs. The evolving role of echocardiography in facilitating the identification of optimal pump speed settings in patients supported by continuous-flow LVADs will be discussed, along with a summary of the protocol we use for image acquisition and reporting. Furthermore, we will provide a summary of echocardiographic findings associated with continuous-flow LVAD-related complications and device dysfunction.Second-generation continuous-flow LVAD rotary pumps offer several advantages over pulsatile first-generation pumps, including smaller size and, importantly, greater long-term mechanical reliability. The different types of continuous-flow LVADs and device characteristics, including pump speeds, are listed in Table 1. The rotating impeller within the pump generates either axial flow (blood flow parallel to the impeller axis) or centrifugal flow (blood flow at a right angle to the impeller axis) from the left ventricular (LV) apex, through the device, to the ascending aorta. The HeartMate II (HM II; Thoratec Corp, Pleasanton, CA) is the only continuous-flow pump approved by the US Food and Drug Administration to act as a bridge to cardiac transplantation and as destination therapy. Operating speeds for this device are between 6000 and 15 000 revolutions per minute (rpm), which clinically translates …