Role of contrast CT for the diagnosis and the prognosis of suspected LVAD thrombosis

BACKGROUND: There is an urgent need for further studies evaluating the role of imaging modalities in the management of left ventricular assist device (LVAD) thrombosis. This study reviews the role of computed tomography (CT) in the diagnosis of suspected LVAD thrombosis. METHODS: All contrast chest CTs performed in patients with suspected LVAD thrombosis at the University of Minnesota between January 2008 and April 2014 were reviewed. Significant CT findings were identified, operative notes were reviewed, and patient outcomes were reported. RESULTS: A total of 32 contrast chest CT examinations were performed in 24 patients with suspected LVAD thrombosis. LVAD thrombus was identified on CT in two patients (one in the outflow graft and one in the inflow cannula), and complications were found in two patients (one with inflow cannula malposition and one with outflow graft stenosis at aortic anastomosis site). Thirteen patients (67%) underwent LVAD explantation for clinically presumed LVAD thrombosis (LVAD exchange in seven, orthotopic heart transplant in six). LVAD thrombus was confirmed at the time of surgery in eight patients (62%; six in the motor, two in the outflow graft). CONCLUSIONS: CT has a low sensitivity but high specificity for detecting LVAD thrombus. The sensitivity is higher, but still modest for the detection of thrombus in the outflow cannula.