Proximal outflow graft extrinsic compression of the Heartmate 3 centrifugal flow left ventricular assist device resulting in pump dysfunction

We herein report an unusual life-threatening complication with the Hearmate 3 centrifugal ventricular assist device: proximal outflow graft extrinsic compression due to external thrombus leading to pump dysfunction and urgent heart transplantation. Low flow alarms without other abnormalities lead to the diagnosis of outflow occlusion. There was no evidence for a twist of the outflow graft, and no evidence for outflow thrombosis. The location of the outflow occlusion was particularly difficult to diagnose due to metallic artifacts around the pump. This report underscores that this complication should be screened in case of persistent low-flow alarms with the Heartmate 3 centrifugal pump.