 The objectives are to assess the efficacy and safety of the Proteus DigitalTM micro-sensor in an exploratory investigation among heart failure patients with LVADs. Medication adherence, specifically to anticoagulation is critically important in the post-implant period to maintain LVAD function and to decrease thromboembolic complications; however, commonly results in significant bleeding resulting in significant morbidity and mortality. In addition, the anticipated degree of anticoagulation is unpredictable after LVAD implantation due to factors related to changes in hepatic blood flow and endothelial dysfunction. Enrolling 10 patients will provide results into the function of micro-sensor and to provide a preliminary assessment of sensor-based activity, signal strength and signal duration in LVAD recipients. Participants will be enrolled during an in-patient hospitalization to assess the efficacy and safety of the device in a monitored setting. 