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Per the instructions for use (ifu), balloon rupture is a potential risk of the tavr procedure.The device was not returned for evaluation.A dhr review was performed and did not reveal any manufacturing nonconformance issues that would have contributed to the complaint event.Imagery was provided of the patient's anatomy and the patient's stj had severe calcification present.Transcatheter delivery balloon burst complaints have been previously investigated by edwards and documented in a clinical technical summary written by edwards lifesciences.A detailed root cause analysis revealed that it is very unlikely that a product defect contributes to this type of event.There are extensive manufacturing inspections in place to prevent this type of malfunction (visual and dimensional inspections, leak testing, and functional balloon burst testing performed to every manufactured lot).The thv delivery system balloons are subject to increased risk of burst due to contact with a highly calcified annulus.Analysis revealed that these types of ruptures are typically caused by puncture from calcium on the native aortic valve when the inflated delivery system balloon comes in contact with the native annular calcification at full inflation/deployment.The burst balloon was unable to be confirmed due to unavailability of the complaint device and relevant imagery.Since the device was not returned, engineering was unable to perform any visual, functional, or dimensional analysis, and therefore no manufacturing non-conformances were able to be identified.The 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 deployment of balloons on thv delivery systems are subject to increased risk of burst in a calcified landing zone.As reported and per the imagery provided, 'the patient's stj was severely calcified and small with sharp protruding calcification noted'.The presence of calcification can create a 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 following mechanisms such as puncture, local overstretching, open cell impingement, or stress concentration.Additionally, it was noted that an additional volume of +3cc was added to the balloon.The prescribed nominal inflation volume is provided in the ifu that was documented in the technical summary.It is possible the balloon was overinflated, subjecting the balloon to pressures high enough to cause the balloon to burst.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.Review of available information suggests that patient factors (calcification) and procedural factors (over-inflation) contributed to the balloon burst.
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