Correction to h6; component code, type of investigation, investigation findings, investigation conclusion.The commander delivery system was not returned for evaluation.Without the device returned for evaluation, visual inspection, functional testing, and dimensional analysis were unable to be completed.Procedural and patient imagery were returned, and the following was observed: the patient's mitral valve exhibits evidence of calcification, photo imagery shows that the nosecone separated from the delivery system, and the balloon material separated from the inflation balloon.A device history record (dhr) review was performed and did not reveal any manufacturing non-conformances that would have contributed to the complaint event.A lot history review was performed and revealed no other complaints relating to the complaint code.The following instructions for use (ifu) were reviewed: commander delivery system with s3, delivery system esheath+ introducer set device prep manual, delivery system esheath+ introducer set procedural manual (us), and valve-in-valve mitral position supplemental training manual.Based on this review, no ifu/training deficiencies were identified.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.The complaints for balloon burst, system components separate during use, and withdrawal difficulty were confirmed by an imagery review of the complaint device.However, no manufacturing non-conformance was identified during the evaluation.The complaint unable to cross the septal wall was unable to be confirmed as neither the complaint device nor applicable procedural imagery was provided for evaluation.Due to the unavailability of the device, engineering was unable to perform any visual, functional, or dimensional analysis; therefore, a manufacturing non-conformance was unable to be determined.Additionally, a review of the dhr and lot history did not provide any indication that a manufacturing non-conformance would have contributed to the complaint.A review of the ifu and training manuals revealed no deficiencies.An existing technical summary has been documented for root cause analysis on balloon bursts in a calcified landing zone.The technical summary provides a rationale as to why it is unlikely that a product defect or manufacturing non-conformance contributed to this type of event, including factors on why the deployment of balloons on thv delivery systems is subject to increased risk of burst in a calcified landing zone.3mensio imagery and case notes confirm evidence of calcification in the patient landing zone.The presence of calcification can create challenging anatomy for balloon inflation.While the balloons are sufficiently designed and tested for rated burst pressures well above their inflation pressure, calcified nodules can compromise the structure of the balloon wall via the following mechanisms such as puncture, local overstretching, open cell impingement, or stress concentration.As the balloon bursts, the altered balloon profile can be more susceptible to catching on the distal end of the sheath tip/vasculature which would have then led to the experienced retrieval difficulty.As a result, additional pull force/excessive device manipulation could have been applied to overcome the withdrawal difficulty which then led to the reported separation.In addition, the technical summary outlines the extensive manufacturing mitigations in place to prevent this type of malfunction (visual and dimensional inspections, leak testing, and functional balloon burst testing that occurs with every manufactured lot).These inspections and testing further support that it is unlikely that a defect present in manufacturing contributed to the complaint.The technical summary also outlines the instructions for valve deployment.It should be noted that these mitigations are still in place.In this case, a review of available information suggests that patient factors (calcification) contributed to the balloon burst while procedural factors (withdrawal of burst balloon, excessive manipulation) contributed to the withdrawal difficulty and separation.As reported, "the rep indicated it was difficult crossing the interatrial septum, was tight to cross with the equipment." per the training manuals, difficulty crossing the septal wall can be caused by the following factors: flexing delivery system incorrectly, orienting e-logo incorrectly, patient anatomy not accurately assessed, user torques delivery system, and balloon shaft not locked after valve alignment.It is possible that the interatrial septum was not adequately dilated for the delivery system to advance through, resulting in the reported crossing difficulty.However, without applicable procedural imagery, a definitive root cause is unable to be determined at this time.Complaint histories for all reported events are reviewed against trending control limits monthly, and any excursions above the control limits are assessed and documented as part of this monthly review.No corrective or preventative actions are required.
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