Left ventricular assist device thrombosis in the setting of left ventricular recovery

Abstract

Figure 1 A ring of thrombus can be seen at pump bearing near the inflow cannula. Left ventricular assist device (LVAD) thrombosis has become increasingly recognized as a complication of mechanical circulatory support. Morbidity, including increased rate of stroke, and a marked increase in mortality are seen with LVAD thrombosis. Current management strategies for LVAD thrombosis include pump exchange, urgent transplantation, medical management, and pump explantation to recovery. The following report is a description of LVAD thrombosis occurring in the setting of left ventricular (LV) recovery. A 51-year-old white woman with non-ischemic cardiomyopathy underwent placement of a HeartMate II (Thoratec, Pleasanton, CA) LVAD as destination therapy and, after discharge, was enrolled in the RESTAGE clinical trial (ClinicalTrials.gov Identifier NCT01774656 [http://clinicaltrials. gov/ct2/show/NCT01774656?term=RESTAGE]. Her medica tions had been optimized per protocol, and serial cardiac echocardiograms demonstrated improving LV function. As the LV cavity size decreased and ventricular tachycardia was noted, the LVAD speed was reduced to 8,400 rpm 2 months after implantation. Approximately 9 months after LVAD placement, the patient presented to the emergency department following 3 firings of her implantable cardiac defibrillator for ventricular tachycardia. The patient was hemodynamically stable without signs or symptoms of heart failure, but laboratory analysis was suggestive of hemolysis, including anemia (hemoglobin 8 g/dl), elevated lactate dehydrogenase of 2,100 IU/liter, and a serum free hemoglobin of 43.5 mg/dl. International normalized ratio was 2.0. The patient was admitted for suspected LVAD thrombosis. Low-flow alarms were present on LVAD interrogation, and urinalysis confirmed hematuria. Intravenous heparin therapy was initiated. Computed tomography angiography confirmed satisfactory positions of the LVAD cannulas. Right heart catheterization and echocardiography were performed to assess for hemodynamic dependence on LVAD. On right heart catheterization, cardiac index was 2.34 liter/min/m by