Engineering investigation: the device in question was returned and upon initial inspection had the stent dislodged in the distal direction toward the distal tip.The crimped stent diameter was measured and was 2.1mm.This diameter is indicative of the (b)(4) stents measured during the quality performance testing inspection.The returned device balloon surface was evaluated to determine if the stent was crimped properly during manufacturing, when the stent is crimped on to the folded balloon the stent frame leaves impressions of the stent frame on the surface of the balloon.The crimped stent impressions were clearly visible indicating that the stent was properly crimped during manufacturing.A full review of the catheter lot history records for the devices in question was performed.The records indicate that this lot of catheters passed atriums final lot qualification testing.This inspection requires that the catheter lot must pass the following: ability of the stent and delivery system to be passed through the labeled introducer sheath.Ability to deploy the stent at nominal pressure (8atm).Ability to withdraw the deflated balloon catheter back through the labeled introducer sheath.Ability of the delivery system to withstand 5 inflate/deflate cycles at the rated burst pressure (12atm) without leaks or failures.Balloon burst testing.The balloon must burst over the rated burst pressure specified on the label (12atm) result: all (b)(4) quality inspection samples passed this final inspection without any non-conformances noted during the final lot qualification testing.Conclusion: based on the details of the event and the successful lot qualification test data, atrium can find no fault with the lot of stent delivery systems in question.Clinical evaluation: the procedure was a fenestrated endovascular aneurysm repair that required a large sheath in order to advance several devices at the same time to the target sites.If the delivery catheter comes in contact with one of the other devices or the endograft itself it could get caught and pulled off the catheter.If a stent becomes dislodged during deployment this may result in the need for further surgery or intervention to prevent complications.The instructions for use state adverse events that may occur with the use of any endoluminal device include, but are not limited to misplacement, migration and occlusion.A stent can become dislodged if the vessel has calcification or severe disease, if the vessel has not been properly pre-dilated, if the stent has not been sized correctly and if the physician uses force to advance or withdraw the catheter.The instructions for use state, "use of the icast is contraindicated in lesions that are heavily calcified or when it is not possible to access the site with standard placement techniques.".
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