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DOI: 10.1055/s-0037-1598794
Micro-Embolic Signals Correlate with Pump Thrombus Formation and Non-Thrombotic Outflow Graft Occlusion in Patients with Left Ventricular Assist Devices
Publication History
Publication Date:
03 February 2017 (online)
Objectives: Micro-emboli are detectable as high intensity transient signals (HITS) with Doppler ultrasound in different clinical conditions including patients with left ventricular assist devices (LVAD). In LVAD patients HITS represent micro-emboli of mostly gaseous nature. The cause of their formation, however, has not been determined.
Methods: From June 2014 to September 2016 LVAD patients were systematically screed for HITS in the LVAD outflow graft by transthoracic echocardiography. The occurrence of HITS was then correlated with pump thrombus formation (PT) and non-thrombotic outflow graft occlusion.
Results: HITS were detected in the outflow graft of 20 LVAD patients (Thoratec Heartmate II n = 12, Heartware HVAD n = 8). HITS correlated with PT in 14 patients (Heartmate II n = 7, HVAD n = 7) and non-thrombotic outflow graft stenosis in 6 patients (Heartmate II n = 5, HVAD n = 1). Patients with PT either underwent thrombolysis (n = 7), pump exchange (n = 2), LVAD weaning (n = 1) or no treatment if no hard clinical treatment indication was present (n = 5). In PT patients HITS disappeared after successful thrombolysis or pump exchange. Of note, pump thrombus formation or non-thrombotic outflow graft stenosis could be macroscopically assured at the time of transplant in the remaining patients.
Conclusion: HITS detection by transthoracic echocardiography identifies patients with pump thrombus formation and non-thrombotic outflow graft occlusion and might develop as a very sensitive screening tool for pump pathology and hypocoagulation monitoring.