MAUDE Adverse Event Report: COOK IRELAND LTD ZILVER PTX 35 DRUG-ELUTING STEN; NIU STENT, SUPERFICIAL FEMORAL ARTERY, DRUG-ELUTING

Device Problem Insufficient Information (3190)

Patient Problems Aneurysm (1708); Surgical procedure, additional (2564)

Event Type  Injury  

Event Description

The physician tried to cross a long chronic total occlusion and went subintimal in the distal sfa.The physician was able to pop back in to the true lumen but was still not able to cross the distal sfa.So, he crossed with spectranetics laser.After crossing, he deployed several overlapping zilver ptx stents.A few months later, the pt came back with pseudoaneurysms.The district manager asked the physician if he thought the pseudoaneurysm was caused by crossing the lesion with the laser.The physician said that he did not think so because there were pseudoaneurysms in the proximal segment and he had not crossed with the laser there.The physician had to realign the zilver ptx stents with viabahn (covered stent).No further adverse effects to the pt have been reported as occurring.As per image review received, 4 zilver ptx stents are involved in the event.Reference also related mdr report numbers 3001845648-2015-00053, 00054, and 00055.

Manufacturer Narrative

The zilver ptx stent involved in this complaint remains implanted in the patient therefore is not available for evaluation.With the information provided a document based investigation was carried out.Three still images of an angiography monitor were provided to support the complaint investigation.According to the information provided by the district manager, photo one was pre-treatment, photo two was post treatment, and photo three was on follow-up angiography at the lime when pseudoaneurysms were discovered.The images are not dated: however from the available complaint information, it is known that a follow-up angiography was conducted a few months after initial stent placement.Images received and reviewed as follows: "findings:.Photo three demonstrates a mid and inferior sfa segment.It overlaps the inferior portion of photo two.Pseudoaneurysms are present at the superior and inferior ends of the shifted stent segment.The image demonstrates 40mm and 60mm zilver stents.The length of most inferior stent cannot be determined.Combining photo two and three, at least four zilver stents and a viabahn were initially placed the pseudoaneurysms developed at the most inferior stent superior end and the most inferior 60mm stent superior end.Impression: although it is possible that the drug coating injured a very thin remnant of vessel wall initially containing the contrast column, the pseudoaneurysms are much more likely related to an extravascular or near extravascular recanalization than the drug coating.First, the drug should have diffusely involved the sfa rather than occurring in just two locations.Second, the initial placement of a mid-proximal sfa viabahn stent demonstrates that this segment likely ruptured during the initial procedure.This segment was most likely intraluminal based on the imaging and the complaint report.Rupture in this location demonstrates the vessel was very fragile.Third, the pseudoaneurysms developed at the ends of a rightward shift in the stent's course.The shift corresponds to intramural spiraling with intraluminal exit and reentry at each end.It is at the beginning and end of an intramural recanalization that the vessel is often weakened most severely- first by probing and then by the acute course change of the stents.Last, the more inferior pseudoaneurysm did involve the distal sfa; the segment acknowledged at risk of being extravascular as it required laser recanalization.Upon review of the only prior known post zilver ptx sfa pseudoaneurysm case, review of coronary artery aneurysm formation post stenting, and review of non-human drug coated stent studies, the most likely cause of aneurysm formation is a near or extravascular stent location rather than the zilver ptx anti-proliferative properties.The ptx was clearly extravascular in the only preceding sfa pseudoaneurysm complaint.The zilver ptx lacks polymer associated with a vigorous inflammatory potential.Failed past attempts to exclude aneurysms with uncovered stents demonstrate that neointimal hyperplasia could not prevent pseudoaneurysm development.Drug coated coronary stents are no more prone to coronary aneurysm formation than bare metal coronary stents.(j am coll cardio intv 2008,1(10):14-21.) in this case, the recanalization channel was extra or near extravascular and steered back into the lumen by chance or laser reentry.Consequently, the pseudoaneurysms would have likely developed whether the zilver was coated or not.Based on the images provided, the customer complaint can be confirmed as pseudoaneurysms were demonstrated at the superior and inferior ends of the shifted stent segment.According to the image review, the most likely cause of aneurysm formation is a near extravascular or extravascular stent location rather than the zilver ptx anti-proliferative properties.Pseudoaneurysms would have likely developed whether the zilver stent was coated or not.Based on the above it can be stated that it is unlikely that this event could have occurred due to zilver ptx stent malfunction.As per instruction for use, pseudoaneurysm formation is listed as a potential adverse events associated with the placement of this device prior to distribution all zilver ptx devices are subject to visual inspection and functional checks to ensure device integrity.A review of the relevant manufacturing records could not be conducted as no lot number was provided.According to the initial reporter, the physician had to realign the zilver ptx stents with viabahn (covered stent) and the patient did not experience any adverse effects due to this occurrence.Quality engineering will continue to monitor complaints of this nature for potential emerging trends.

• Brand Name: ZILVER PTX 35 DRUG-ELUTING STEN
• Type of Device: NIU STENT, SUPERFICIAL FEMORAL ARTERY, DRUG-ELUTING
• Manufacturer (Section D): COOK IRELAND LTD; limerick ; EI
• Manufacturer Contact: sinead quaid, sr specialist ; 61334440
• MDR Report Key: 4608496
• MDR Text Key: 22036024
• Report Number: 3001845648-2015-00056
• Device Sequence Number: 1
• Product Code: NIU
• Combination Product (y/n): N
• Reporter Country Code: US
• PMA/PMN Number: P100022/S001
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: Health Professional,User Facility,Company Representative
• Reporter Occupation: Unknown
• Type of Report: Initial
• Report Date: 02/16/2015

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Date FDA Received: 03/12/2015
• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: No
• Device Operator: Health Professional
• Other Device ID Number: UDI: UNK
• Was Device Available for Evaluation?: No
• Was the Report Sent to FDA?: No
• Event Location: Hospital
• Date Manufacturer Received: 02/18/2015
• Was Device Evaluated by Manufacturer?: Device Not Returned to Manufacturer
• Is the Device Single Use?: Yes
• Is This a Reprocessed and Reused Single-Use Device?: No
• Type of Device Usage: Initial
• Patient Sequence Number: 1
• Patient Outcome(s): Life Threatening; Required Intervention
• Patient Age: 85 YR