Role of Echocardiography in the Evaluation of Left Ventricular Assist Devices: the Importance of Emerging Technologies

Abstract

The role of left ventricular assist devices (LVAD) in patients with end-stage heart failure is well known, both as a temporary treatment before transplantation and as destination therapy, in a scenario of a relative shortage of donors to satisfy the increasing requests for transplantation. The increased population of LVAD patients needs careful imaging assessment before, during, and after LVAD implantation; echocardiography is the best tool for their evaluation and is considered the diagnostic technique of choice for the assessment before, during, and after device implantation. Although the conventional echocardiographic assessment is quite effective in evaluating the main critical issues, the role of new technologies like three-dimensional echocardiography and myocardial deformation measurements is still not properly clarified. In this review, we aim to provide an overview of the main elements that should be considered in the assessment of these patients, underlining the role that could be played by new techniques to improve the diagnostic and prognostic effectiveness of echocardiography in this setting.

A new pathophysiology in heart failure patients

“…The intraventricular dynamics of the flows and the kinetic energy distribution present interesting differences between the native ventricle with reduced ejection fraction and the ventricle with implanted LVAD 16 . In the native ventricle, the flow presents a peculiar, well‐defined pattern: from the mitral valve, blood flow is posterolaterally directed toward the apical region, along the wall of the ventricle, from where it changes direction toward the aortic valve.…”

“…Specifically, patients with a LVAD could be evaluated in light of the peculiar intracardiac hemodynamic pattern due to the effects of continuous flow in the heart as well as in the peripheral vessels. Specifically, LVAD influences the left ventricular mechanics in all its phases 16 . However, intraventricular mechanical analysis in LVAD patients is rarely performed, and it is not a part of routine ultrasound evaluation.…”

“…heart failure, LVAD therapy, pathophysiology ventricle with implanted LVAD. 16 In the native ventricle, the flow presents a peculiar, well-defined pattern: from the mitral valve, blood flow is posterolaterally directed toward the apical region, along the wall of the ventricle, from where it changes direction toward the aortic valve. In ventricles with LVAD, the presence of the axial vortex and the size of the cannula determine a lower uniformity of kinetic energy distribution, and a significant slowing of flow in the apical site (Figure 1).…”

Left Ventricular Assist Device Infections

“…However, it has been previously acknowledged that echocardiography may be of limited use in evaluating for vegetations, due to reflections off of the device's reflective metal surfaces [50]. The role of echocardiography [70] and the application of newer techniques such as real time three dimensional (3D) echo has been reviewed [71] and discusses utility in evaluating native valves and presence of thrombus.…”

Changes in left and right ventricular two-dimensional echocardiographic speckle-tracking indices in pediatric LVAD population: A retrospective clinical study

“…However, most of these studies are focused on the research of predictors of RV failure post LVAD implantation, and most important, all of them are focused on adults. [11][12][13][14][15][16] Our objective was to study the changes in 2DSTEderived myocardial tissue deformation indices of LV and RV during short-term and long-term support in children with pulsatile-flow LVAD.…”