title: Treatment of thrombus formation associated with the MicroMed DeBakey VAD using recombinant tissue plasminogen activator.
abstract: BACKGROUND
  The latest generation of left ventricular assist devices consists of nonpulsatile impeller pumps. In these small pumps, thrombus formation inside the device does not lead to thromboembolic end-organ dysfunction but may dramatically impair pump flow. We report on our experience with thrombus-related pump dysfunctions of the MicroMed DeBakey left ventricular assist device and its treatment.
  
  
  METHODS
  Eight of 22 patients with a MicroMed DeBakey VAD presented with a critically reduced pump flow. In 7 cases, an increased power demand indicative of progressive thrombus formation associated with the device was evident, whereas 1 case presented with thrombus formation within the inflow conduit associated with a very low power demand. Brief spontaneously resolving pump stops had been noted in 6 patients. All 8 patients were treated with 100 mg of recombinant tissue plasminogen activator (rt-PA), administered via an IV line.
  
  
  RESULTS
  Rt-PA lysis led to an increase of pump flow along with a reduction of power demand within a short time in all patients. No severe bleeding complications occurred. However, 4 patients experienced transient epistaxis. All patients could be discharged from intensive care immediately after discontinuation of thrombolytic therapy.
  
  
  CONCLUSIONS
  Rt-PA lysis is a very effective tool for thrombus-related pump dysfunction in patients with impeller pumps, which renders emergency surgical exchange unnecessary in most cases.
mesh_terms: D000293:Adolescent; D000328:Adult; D003328:Coronary Thrombosis / Q000188:drug therapy* / Q000209:etiology / Q000473:pathology; D005260:Female; D005343:Fibrinolytic Agents / Q000627:therapeutic use*; D006353:Heart-Assist Devices / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011994:Recombinant Proteins / Q000627:therapeutic use; D010959:Tissue Plasminogen Activator / Q000235:genetics / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D005343:Fibrinolytic Agents; D011994:Recombinant Proteins; D010959:Tissue Plasminogen Activator