The device was received and inspected.Upon initial inspection the stent was still in its original crimped position between the radiopaque marker bands and was securely in position.The proximal and distal balloon cones were slightly opened and had dried blood within the balloon.This indicates that there was a leak in the system.The shaft at the proximal balloon weld was also badly kinked and damaged and the balloon badly deformed.The manifold of the catheter has been removed as well and not provided with the returned device.To determine if the device would have been functional a toughy-borst adapter was placed over the shaft where the manifold had been removed and a 20cc syringe filled with water attached to the adapter.The tip of the catheter was clamped to prevent the fluid escaping through the guidewire lumen.Upon attempting to deploy the stent a gross leak was noted at the proximal balloon weld.The leak prevented pressure from entering the balloon.It appears that based on the condition of the returned product that there is a strong possibility the guide wire apposition was lost during the procedure.The details provided indicated that "the stent/balloon had been folded over".For the stent and balloon to have been folded over the stent and balloon would have had to have been outside the introducer sheath and no wire within the guidewire lumen of the catheter at the area of the proximal balloon weld.If the guide wire was then advanced it is possible that the wire could go through the catheter wall if enough force was generated.Flouroscopic images of the procedure were provided and are difficult to determine the series of events based on these images.The first image shows what looks like the balloon/stent inside of a previously deployed stent.There is no sign that the wire is in place at this time and is possible that the stent has actually folded over in this image.There appears to be no guide wire extending beyond the intended target.In this case the previously deployed stent.The second image shows the stent outside of the introducer sheath and actually next to the sheath.It appears also that the balloon/stent are folded over and again no visible presence of a guidewire protruding outside the distal tip of the catheter.During the process of manufacturing every catheter produced is 100% pressure tested at the rated burst pressure of the product (10atm) following manufacturing procedure catheter leak check to ensure the integrity of the catheter system.The leak observed in the balloon weld of the catheter was a gross leak and would have been easily detected at this process step in manufacturing.During the stent crimping operation 12mm v12/icast otw stent delivery system the process requires the stent to be held in the crimped head and a positive pressure of 285psi be held for 40 seconds to the entire system.If a gross leak developed or was present at this operation it would have created an audible pop and or hiss from the air leaving the catheter system.The proximal weld area and distal weld area of every device manufactured in visually inspected at 20x magnification for any defects (voids/moisture defects and embedded particulate in the weld zone, incomplete or excessive welds, gaps at the weld, and collapsed lumens per the visual aid and manufacturing procedure balloon proximal thermal welding, otw stent delivery, 12mm ld.As this hole in the proximal weld was very easily seen it surely would have been detected during one of the many process procedure steps of manufacturing.A review of the device history records show that this lot of large diameter v12 catheter assemblies passed all quality and performance requirements without any non-conformances noted during the manufacture of the production lot of catheters.The equipment used in the manufacturing process was also reviewed and found to have been set-up properly.During the lot qualification testing that every advanta v12 is tested to, the proximal balloon weld test data was evaluated to ensure it met the minimum proximal weld tensile requirements.The proximal balloon weld tensile force requirement as documented in the product part specification drawing ps004362 ¿balloon catheter, otw stent delivery, 2l, 12mm¿ is that the minimum tensile strength of the proximal balloon bond should be 18n.The data as documented in the device history records show that the minimum tensile strength was 25 n.This exceeds the requirement by 7n.Based on the review of the details, the images received and evaluation of the returned product, the complaint cannot be confirmed.There is no evidence to conclude that the device was faulty.The product met all quality and performance requirements at the time of manufacture.The most probable cause is that guide wire apposition was lost causing the stent/balloon to fold over during advancement and upon attempting to advance the guide wire back through the lumen, the wire ruptured through the catheter shaft due to the bend at the proximal weld area.
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