Section d7, h4, h6 (patient code): correction.Section d10, h3: additional information.Manufacturer's investigation conclusion: the evaluation of heartmate ii lvas, serial number (b)(6), identified an internal driveline issue that could have contributed to the report of the pump not being able to maintain the set speed while connected to the power module, which was confirmed through the evaluation of the submitted system controller log file.The submitted log file captured several transient pump stops and low speed hazard events from 21:39:35 through 21:52:29 on (b)(6) 2020 while at least one system controller power cable was connected to a power module.Power elevations up to 19.7 w were observed during some of these events, and low flow hazard events were noted at times when a low speed hazard was active by design.It was reported that the patient underwent a pump exchange to a heartmate 3 on (b)(6)2020.(b)(6) was returned assembled with the driveline severed approximately 6¿ from the pump housing.The distal end of the driveline was returned in a segment measuring approximately 32¿, and the remainder of the driveline was not returned.Internal metal braided shield breakdown was observed approximately 9.5¿ through 10.5¿ from the pump housing.Electrical continuity testing of the driveline revealed that a short to shield was able to be induced in the yellow wire upon manipulation of the driveline at the location of the observed metal braided shield breakdown.Visual inspection of the underlying wires of the driveline revealed a breach in the insulation of the yellow wire approximately 9.5¿ from the pump housing, exposing the inner conductors.This damage appears consistent with fatigue failure due to repetitive flexing and abrasion against the metal braided shield.If the exposed inner conductors of the yellow wire made contact with the metal braided shield while the system controller was tethered to a grounded power source such as the power module, the resulting electrical short to ground could have resulted in the pump stops and low speed events observed in the submitted log file.Incidental findings: upon disassembly of the motor capsule from the outlet housing, a significant amount of silicone material appeared to have been removed from the motor capsule and adhered to the interior of the outlet housing.An exact duration that the silicone was adhered to the outlet housing and a specific cause for this finding could not be conclusively established through this evaluation.The silicone encapsulation issue did not appear to have affected device functionality.The relevant sections of the device history records for (b)(6) were reviewed and showed no deviations from manufacturing or quality assurance specifications.The implant kit was shipped on (b)(6)2018.The heartmate ii lvas patient handbook contains a section on ¿caring for the driveline¿; however, all heartmate ii lvad drivelines have the potential for wire/shield breakdown to occur dependent upon length of use and patient handling.Section 5 entitled ¿alarms and troubleshooting¿ outlines all system controller alarms and provides information regarding how to respond to and troubleshoot the alarms.Heartmate ii lvas ifu section 6 entitled ¿patient care and management¿ outline indications of driveline damage as well as how to respond to such events.Section 7 entitled ¿alarms and troubleshooting¿ outlines all system controller alarms, including the low flow hazard alarm, and provides information regarding how to respond to and troubleshoot the alarms.No further information was provided.The manufacturer is closing the file on this event.
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