Imaging in Mechanical Circulatory Support: Computed Tomography

Transthoracic echocardiography is an integral and the first line imaging modality before and after LVAD placement to provide hemodynamic and structural assessment, in particular for the evaluation of post implant cardiac function, device function optimization and detection of complications. Body habitus, the need for a good acoustic window, the presence of acoustic shadowing from LVAD metallic components, as well as post-surgical changes can limit the use of echocardiography. The American Association for Thoracic Surgery/International Society for Heart and Lung Transplantation recommend the use of 3-D multi-slice computed tomography (MSCT) angiography for evaluation of LVAD graft obstruction and/or pump malposition. MSCT has been used in all aspects of LVAD care, including pre-surgical planning; evaluation of complications included the assessment of potential obstruction of the LVAD system, which can be classified into pre-pump (inflow cannula [IC]), intra-pump (the motor) and post pump (outflow cannula [OC]) [Scandroglio AM, et al. J Am Coll Cardiol, 2016, 67, 2758–68]. In addition, MSCT also plays a role in LVAD infection assessment. Fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography computed tomography (PET/CT) has been described as a useful modality in the evaluation of LVAD infection, especially when there is diagnostic uncertainty after initial testing.