Inflow cannula obstruction of the HeartWare left ventricular assist device: what do we really know?

In the setting of HeartWare left ventricular assist device (HVAD, Medtronic) implantation, pre-pump blood flow obstruction has been described due to intraventricular thrombus formation occluding the inflow cannula. This phenomenon often evolves in suboptimal pump performance, and requires prompt management to prevent its progression. However, to date, effective strategies and tools for the diagnosis and management of this complication are poorly described. We report a case of HVAD inflow cannula obstruction that drove later in-pump thrombosis and, eventually, complete cannula occlusion, and discuss gap of knowledge and limitations of currently available diagnostic and therapeutic tools in this scenario. Furthermore, we reinforce the value of time-frequency analysis of the HVAD log files to early identify abnormal pump operation associated with inflow cannula obstruction despite unremarkable trends of pump parameters.