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The commander delivery system was returned to edwards lifesciences for evaluation.Visual inspection revealed a kink in the balloon shaft due to packaging, distal end of the delivery system stuck inside the sheath housing (balloon spring is damaged and guidewire lumen has separated), balloon separation at i/c bond, crimped valve not centered between the alignment markers, uneven flex tip gouging is indicative that valve diving occurred, adhesive attaching spring to guidewire lumen present, adhesive attaching end of guidewire lumen to nose tip assembly present, distal tip split on esheath, crack observed on tab ring, and tab ring unseated from slider (the tab ring likely unseated from the slider and cracked as a result of excessive torque being applied to it).Because the unseated tab ring was not reported, and nothing was noted during initial evaluations following receipt of the device, it is likely damage occurred during handling afterwards.Presence of adhesive on the guidewire shaft indicates that the guidewire shaft and nose tip assembly of the device were properly attached during manufacturing.Functional testing was performed and full fine adjust was able to be used after locking the balloon shaft at the warming marker.Additionally, the locknut/collet engagement force was within specification.Dimensional testing was performed on the double wall thickness of the crimp balloon and was found to be in within specification.In addition, the critical dimensions of the tab ring were also measured and were found to be above specification.However, because the component is pliable, deformation likely occurred when the tab ring was unseated and cracked during handling post-procedure.Procedural cine was provided and reviewed and the following observations were made: the valve diving occurred during valve alignment when placing the valve between the alignment markers.Cine was not provided of gross valve alignment and use of fine adjust (cine shows valve was already between the markers); therefore, it is unclear when valve diving started (i.E.During gross alignment or use of fine adjust).The physician was able to correct the diving.The valve moved proximally after retracting the flex tip from the native annulus to the triple markers.Resistance pulling valve into sheath occurred when valve was halfway past the sheath distal tip.The delivery system/sheath were retrieved as a unit, and the nose tip was still intact at this point.During balloon manufacturing, the balloon was 100% inspected for the following: working length, balloon diameter, proximal and distal leg ids, proximal leg od, and double wall thickness measurements.The balloon is 100% visually inspected for mechanical damage, defect, and deformation.The flex tip od is inspected during the flex tip assembly and bonding process.The nose tip/guidewire shaft bond is visually inspected.The crimp balloon to inflation balloon laser bond is inspected for defects or burns.The marker band is inspected to ensure the markers bands are completely showing after insertion into marker band placement tool and adequate adhesive coverage.The delivery system balloon undergoes 100% inspection for distorted/pinched folds and the balloon size is inspected.During final inspection the entire device from distal to proximal is visually inspected for missing components, incorrect assembly, device damage (e.G.Kinks, cuts), inflation/crimp balloon for distorted/pinched folds.During functional inspection, the fine adjust is inspected by ensuring if the balloon shaft and wind nut move together when the fine adjust knob is rotated and the wing nut is locked and the collet engagement is also inspected.During product verification (pv) testing, the delivery system is inspected for kinks and cracks, loose or missing components.The fine adjust functionally is verified.The balloon inflation/deflation time is tested, and retrieval force of system through sheath.The lot met statistical requirements as it exceeded the acceptance criteria of a lower specification limit.The inflation/crimp balloon bond was visually inspected and any delivery system with damaged bond is discarded.Testing was performed for the locknut/collet engagement force, the inflation balloon/crimp balloon tensile force, and the balloon spring/guidewire shaft tensile force, and all met statistical requirements.The above inspections during the manufacturing process and testing performed during pv support that it is unlikely a manufacturing non-conformance contributed to the reported.Review of history for lot revealed no similar complaints.A review of edwards lifesciences risk management documentation was performed for this case.The reported event is an anticipated risk of the transcatheter heart valve procedure, additional assessment of the failure mode is not required at this time.In this case, the crimped valve remained on the balloon because the balloon did not inflate, and the delivery system/valve was successfully retrieved with no patient impact.The complaints were confirmed through visual inspection and available imagery.A review of complaint history and manufacturing mitigation revealed no indication that a manufacturing non-conformance contributed to the event.A review of ifu/training materials revealed no deficiencies.A review of complaint history suggests that the following procedural and patient factors may have contributed to increased valve alignment forces, causing difficulty with valve alignment, fine adjust difficulty, and subsequently resulting in balloon torn and valve movement on balloon.A product risk assessment (pra) was previously initiated to investigate and document crimp balloon tears and valve movement on balloon and their associated risks, respectively.Both pras identify increased alignment forces experienced during the procedure as possible causes of both events (i.E.Tear adjacent to i/c bond and valve movement during flex tip retraction at the native annulus).Increased alignment forces can result from the following: performing valve alignment at a bend or angle (such as in a non-straight section of the aorta) can cause increased alignment forces.Additionally, performing valve alignment at a bend angle can cause the thv to unseat (non-coaxial placement of valve in relation to the flex tip) from the flex tip during alignment and ¿dive¿ into the lumen of the flex tip, resulting in even higher alignment forces.Under simulated conditions (tortuous anatomy), a previously performed engineering study was able to recreate high valve alignment forces with and without valve diving.Residual volume left in the balloon may also contribute to increased forces during valve alignment.This was recreated in a previously performed engineering study.A capa was previously initiated for further investigation and potential corrective/preventive action(s) regarding ¿delivery system ¿ valve movement on balloon¿.Visual inspection of the device and procedural cine reveals that valve diving did occur, suggesting that there were increased alignment forces present.Increased alignment forces would have led to difficulty with pulling the balloon shaft backwards during gross alignment, or using the fine adjust function during fine alignment, in addition to weakening and/or tearing the crimp balloon adjacent to the i/c bond.Subsequent release of the built up tension, by retracting the flex tip, could cause the valve to move off the balloon.Difficulty withdrawing the valve through the sheath occurred when half of the valve was past the sheath distal tip.If the valve was not coaxial with the flex tip, or a valve strut was caught on the sheath tip, difficulty or resistance during withdrawal may occur and subsequently lead to the sheath distal tip tear.Per procedure, the valve should be centered on the flex tip and the delivery system should be locked prior to retrieval, and excessive force should not be used.Additionally, instructions are provided stating that if resistance is felt, it may be because the valve is caught on the sheath tip.In such an event, the valve should be advanced past the sheath tip, and the delivery system should be rotated after ensuring the valve is centered on the flex tip, before trying again.After the entire valve is inside the sheath, just past the tip, the sheath and delivery system should be removed as a unit.While there is imagery provided of the initial sheath/delivery system withdrawal as a unit, it is unknown how the devices were subsequently handled/manipulated.It is possible that at some point (i.E.Either towards the end of retrieval, or after the devices were out of the patient), the delivery system was attempted to be pulled out of the sheath, causing the nose tip of the delivery system to become separated and stuck inside the sheath housing.The complaints were confirmed, but no manufacturing non-conformities were found in the returned sample.In this case, available information suggests patient/procedural factors may have contributed to the events however, a definitive root cause is unable to be determined at this time.Review of complaint history revealed that the occurrence rate did not exceed the march 2018 control limit for the respective applicable trend categories.No labeling or ifu inadequacies have been identified and review of complaint history revealed that the occurrence rates do not exceed control limits for the respective trend categories.Therefore, no corrective or preventative action is required.
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