Manufacturer's investigation conclusion: although multiple yellow wrench advisories associated with driveline faults were confirmed via the submitted log file, the entire portion of the driveline was not returned and a specific cause for the driveline faults could not be confirmed.Additionally, evaluation of heartmate ii lvas, serial number (b)(6), confirmed driveline (dl) wire damage.(b)(6) was returned assembled with the dl cut approximately 12" from the pump housing and the distal portion of the dl was not returned.The inflow conduit (inlet tube, flex section, and inlet elbow), the outflow graft, and the outflow graft bend relief were not returned.The outflow elbow was returned connected to the pumps outlet port.Evaluation of the outflow elbow revealed no evidence of depositions or thrombus formations.Visual examination of the pump¿s blood-contacting surfaces upon disassembly of (b)(6) also revealed no evidence of developed depositions or developed thrombus formations.The disassembled pumps bearings, rotor, and blood-contacting surfaces were examined under a microscope and no anomalies were observed.Electrical continuity testing of the dl did not reveal any discontinuities or shorts.However, hipot and visual examination of the dl revealed a breach to the insulation of the brown wire located approximately 8.75¿ from the pump housing.The observed wire damage appeared to be the result of abrasion against the braided shield due to repetitive flexing.The breach in the brown wire is not consistent with the same phase causing the driveline fault alarms, therefore the observed damage is not related to the alarms.Analysis of the submitted log files also revealed multiple yellow wrench advisories associated with driveline faults which were silenced throughout the entirety of the log file.These driveline faults appeared to result from an issue with phase 3.The other phases did not appear to contribute to the fault.The pump remained above the low-speed limit and appeared to be functioning as intended.The heartmate ii lvas ifu and patient handbook outline indications of driveline wire damage as well as how to respond to such events.These documents also address how to care for the driveline; however, all heartmate ii lvad drivelines have the potential for wire/shield breakdown to occur dependent on duration of use and movement/flexing over time.Additionally, these documents outline all system controller alarms as well as the appropriate actions associated with them.No further information was provided.The manufacturer is closing the file on this event.
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