Recurrent short-to-shield phenomenon requiring LVAD exchange: a rare complication

Left ventricular assist device (LVAD) therapy is a common alternative approach for a patient with end-stage heart failure with HeartMate II (HM II) being one of the most common LVAD implants. The short-to-shield (STS) phenomenon is an uncommon drive-line (DL) dysfunction resulted from broken insulator causing an underlying wire to contact a metallic shield in a DL. This leads to a short circuit and a pump stoppage. We reported a case of 66-year-old man status post-implantation of HM II who presented with STS phenomenon. A tear at the distal end of the DL was found, and the patient underwent replacement of the extracorporeal part of DL twice. After the second repair, the pump functioned normally when tested in the hospital but the STS occurred again at home. The patient then underwent LVAD replacement surgery and insulation breach was found at one of the wires in intracorporeal part of the DL. After the surgery, the patient sustained recurrent episodes of STS and had to undergo a third extracorporeal DL repair surgery. Analysis of the removed DL confirmed an insulation breach. The STS has been resolved since then. Our case is unique as it is very rare to sustain another episode of STS shortly after a pump exchange. It also shows that the occurrence of STS can be intermittent and the area of insulation breach can be different from the area of the visualized tear. As a result, closed monitoring after DL repair must be strictly implemented.