Manufacturer's investigation conclusion: no device-related issues were identified during evaluation of heartmate 3 lvas, (b)(6), that would have contributed to the reported event.A direct correlation between the device and the reported retinal stroke could not be conclusively determined through this evaluation.The suspected device thrombosis could not be confirmed through evaluation of the returned pump.The account reported that the patient was transplanted due to a retinal stroke that was suspected to have originated from device thrombosis.(b)(6) was returned assembled with the pump cable severed approximately 9 inches from the pump header, and the remaining portion of the pump cable as well as the modular cable were not returned.The sealed outflow graft attachment was returned attached to the pump cover outlet port.The outflow graft bend relief was returned attached to the pump with a flexible white tubing material extending the outflow graft bend relief and sutured at the anastomosis.The apical cuff was returned with the cuff lock engaged.Upon disassembly of the returned pump, examination of the blood-contacting surfaces revealed no adhered depositions or thrombus formations that would have contributed to a flow or functional issue.Visual inspection of the pump rotor and rotor well did not reveal any obvious surface scratches or defects.The left ventricular assist device (lvad) event and periodic log files retrieved from the returned device appeared to capture the device functioning as intended.(b)(6) was cleaned, rebuilt, and functionally tested on a mock circulatory loop.The device operated as intended and in accordance with manufacturing specifications.Incidental findings: incidental-ofg obstruction: upon removal of the outflow graft bend relief, a tissue ingrowth at the proximal end of the outflow graft was revealed (figure 1 of reference photos).A larger accumulation of tissue ingrowth between the graft and the bend relief was observed over the deformation.This ingrowth was smooth and appeared to have formed around the deformation, suggesting that the graft had been distorted for an undetermined amount of time while (b)(6) was supporting the patient.The relevant sections of the device history records for (b)(6) were reviewed and showed no deviations from manufacturing or quality assurance specifications.The heartmate 3 left ventricular assist system (lvas) instructions for use (ifu), rev.C, is currently available.Section 1 "introduction" lists adverse events that may be associated with the use of the heartmate 3 lvas, including arterial non-central nervous system (cns) thromboembolism, venous thromboembolism, and pump thrombosis.Section 5 "surgical procedures" (under ¿preparing the ventricular apex site¿) instructs to inspect the ventricular chamber for mural thrombi and crossing trabeculae following removal of the core and to address one or both, as needed.This section also states that pump function will be compromised in the presence of inlet obstruction.Section 5 (under ¿implant procedures¿) additionally warns to inspect the ventricle and remove any previously formed clots that may cause embolism or any trabeculae that may impede flow.Section 5 of the ifu, "surgical procedures", contains information on "preparing the sealed outflow graft" and explains that prior to implantation, the bend relief should be disengaged from the graft for the de-airing procedure.Section 5 also contains a sub-section on "attaching the sealed outflow graft to the aorta", which instructs the user to stretch the graft completely and then measure and cut the sealed outflow graft to the appropriate length.Section 5, under "attaching the sealed outflow graft to the pump", instructs the user to verify that the outflow graft is not twisted or kinked by checking the position of the black line on the graft above and below the bend relief and ensuring that the line is straight.Section 5, under "de-airing the pump", cautions the user: "do not rotate/twist the sealed graft.Check the alignment of the black line on the graft to verify that the sealed graft is not twisted or kinked." this section also explains how to attach the bend relief once the vent needle has been removed from the sealed outflow graft and leaks have been ruled out.Section 1 lists the outflow graft clip as a required component for implant.Section 5 further instructs the user to ¿attach the outflow graft clip to prevent post-operative outflow graft twisting¿ and warns that failure to install the outflow graft clip so that it is flush with the bend relief can allow graft twisting or abrasion which may lead to serious adverse events such as bleeding, graft occlusion, thrombosis, and/or death.Section 6 "patient care and management" (under "anticoagulation") contains information regarding the recommended anticoagulation therapy for patients using the device.This section also lists and thromboembolism as a potential late postimplant complication.No further information was provided.The manufacturer is closing the file on this event.
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