A low-dose thrombolytic infusion protocol for safe and successful treatment of left ventricular assist device thrombosis: a case series

Background Pump thrombosis is a serious complication of continuous-flow left ventricular assist device (CF-LVAD) therapy. In this study, we aim to report a novel protocol of an intermittent, low-dose, and slow infusion of tissue plasminogen activator (alteplase).Case summary We treated seven LVAD pump thrombosis events (HeartMate (R) II and HeartWare) in four patients with a median age of 52 years (31-63), and all were female. The protocol was applied from January 2015 to December 2018, and it consisted of an intermittent, low-dose, and slow infusion of systemic thrombolytic therapy in the intensive care unit. This therapy resulted in successful resolution of pump thrombosis in six out of seven events. Bleeding complication occurred in one patient, which included a ruptured haemorrhagic ovarian cyst and a small cerebellar intra-parenchymal haemorrhage. All patients were discharged home in a stable condition, except one patient who died during hospitalization because of severe sepsis, pump thrombosis with subsequent pump exchange, and multi-organ failure.Discussion A low-dose, prolonged, and systemic thrombolytic infusion protocol is an effective and relatively safe treatment that can lead to a sustained resolution of pump thrombosis with low bleeding complications and failure rates.