The patient was implanted with a left ventricular assist device (lvad).It was reported that the patient was explanted on (b)(6) 2017.During the procedure, a tear in the outflow graft bend relief was observed, and partial thrombosis was found in the outflow graft.The outflow graft had been damaged due to the bend relief causing abrasion and a tear, and thrombus was seen in that area.The patient was not symptomatic prior to the explant.The tear and thrombus were observed upon explant.
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The pump was returned assembled with the driveline cut approximately 11.5 inches from the pump housing; however, the distal portion of the driveline was not returned.Examination of the sealed inflow conduit, the sealed outflow graft, and the outlet elbow revealed no evidence of developed depositions or thrombus formations.The sealed outflow graft was returned severed at its hardware.A remnant of graft material that was left attached to the hardware appeared slightly frayed.A specific cause for this fraying could not be conclusively determined since the graft was cut at the time of the explant; however, the fraying could have resulted from the reported disconnection of the sealed outflow graft bend relief.The sealed outflow graft bend relief was also returned severed at its hardware.One of the bend relief¿s attachment tabs was slightly displaced, but there were no other unusual signs of wear or damage.Upon disassembly of the pump, examination revealed a deposition surrounding the bearing ball within the proximal side of the outlet stator.Its lack of concentric layering indicates that this deposition did not initially form in the outlet stator.The origin of this deposition could not be determined; however, its areas of slight denaturation suggest that it was present while the pump was supporting the patient.A specific cause for the development of this deposition and a correlation to the reported sealed outflow graft bend relief disconnect could not be conclusively determined.Upon removal of the observed deposition, the device was cleaned.The disassembled pump¿s bearings, rotor, and blood-contacting surfaces were microscopically examined and no anomalies were observed.Electrical continuity testing of the driveline did not reveal any discontinuities or shorts.The pump was reassembled and functionally tested under normal operating conditions using a mock circulatory loop.The data retrieved from this testing revealed normal pump power consumption and pressure values, and the device functioned as intended.Reports of disconnection of the bend relief from the sealed outflow graft have been addressed through the manufacturer's corrective/preventative action system, updated device labeling, an urgent medical device correction notice (2916596-2/24/12-001-c) and a sealed outflow graft bend relief collar (sobr collar) used to secure the bend relief to the sealed outflow graft and increase the assembly¿s resistance to forces that would tend to dislodge the bend relief.This design modification was approved in a pma supplement and has been implemented.Device thrombosis is listed in the instructions for use as a potential adverse event that may be associated with the use of the heartmate ii left ventricular assist system.A review of the device history records revealed no deviations from manufacturing or quality assurance specifications.The manufacturer is closing the file on this event.
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