MAUDE Adverse Event Report: COOK INC ZENITH FLEX WITH SPIRAL-Z TECHNOLOGY AAA ENDOVASCULAR GRAFT ILIAC LEG; MIH SYSTEM, ENDOVASCULAR GRAFT, AORTIC ANEURYSM TREATMENT

Model Number	G55247
Medical Device Problem Code	Occlusion Within Device (1423)
Health Effect - Clinical Codes	Stenosis (2263); Claudication (2550)
Date of Event	11/09/2017
Type of Reportable Event	Serious Injury
Additional Manufacturer Narrative
(b)(4).The event is currently under investigation.A follow up report will be submitted upon completion of the investigation.
Event or Problem Description
The area representative reported that a male patient with an abdominal aortic aneurysm (aaa) and common iliac artery (cia) aneurysm had a stand-alone cook iliac side branch (ibd) implanted in 2009.It is believed a left common iliac artery (lcia) covered stent was also implanted and doctor assumes it is self-expanding.In 2013, an aaa repair was performed using the following components, a zenith low profile aaa endovascular graft main body (intro from right side).A right bridging leg using a zenith flex with spiral-z technology aaa endovascular graft iliac leg.A zenith flex with spiral-z technology aaa endovascular graft iliac leg bridging from the contralateral trouser leg into the in situ lcia stent.A zenith flex with spiral-z technology aaa endovascular graft iliac leg on the left side extending all the way up to the contralateral trouser leg; which means there are three fabric layers at this point.The patient has felt an increase in buttock claudication, and ultrasound has shown up to 75% stenosis through the graft limbs.The doctor ordered a computerized tomographic angiography (cta) and booked the patient for surgery.On (b)(6) 2017, after gaining access, the doctor used a transducer and noted a pressure gradient at the distal edge of the zalb right trouser leg, zalb contralateral trouser leg, and where the zenith flex with spiral-z technology aaa endovascular graft iliac leg exits the in situ lcia stent.The doctor relined the two segments on the left, and one on the right, with 3 covered balloon expandable stents (10mm x 38mm on the right, and 2 x 9mm x 38mm on the left).He flared the distal ends of the two stents that extended into the 20mm graft on the right, and 24mm graft on the left with a 12mmx2cm pta balloon.This is the largest the stents would go.He used the transducer again and found the pressure gradient had resolved.The doctor was happy with the result.From the latest cta, the doctor has also noted the lcia has dilated and the distal sealing stent of the zenith flex with spiral-z technology aaa endovascular graft iliac leg has lost apposition.He will monitor and plans to put in an ibd on that side at a later date.Three mfr reports have been filed for the reported issue of stenosis through the graft limbs as listed below: mfr report # 1820334-2017-04258, zsle-20-74-zt - zenith flex with spiral-z technology aaa endovascular graft iliac leg; mfr report # 1820334-2017-04259, zsle-11-39-zt - zenith flex with spiral-z technology aaa endovascular graft iliac leg; mfr report # 1820334-2017-04260, zsle-24-90-zt - zenith flex with spiral-z technology aaa endovascular graft iliac leg.
Additional Manufacturer Narrative
Investigation/evaluation: the actual complaint device was not returned.Without the complaint device, a physical investigation was not able to be completed.Imaging was provided for review.A documentation investigation was performed.A review of the provided imaging, device history records, instructions for use, manufacturing instructions and quality control data was conducted.A computerized tomographic angiography (cta) performed four years after implantation was provided.Since an abdominal aortic aneurysm (aaa) or evidence of a prior aaa was not present, aaa endograft implantation four years after right common iliac (cia) and external iliac artery (eia) aneurysm exclusion was secondary to right cia growth.Per the imaging review, although bilateral endograft leg stenosis is confirmed and pressure drop on direct measurement indisputable, these stenoses were less likely to cause claudication than the patient's l3-4 spinal canal stenosis.First, because the most significant stenosis, the crowded contralateral leg lumen, was present immediately, it must have been asymptomatic because claudication was not reported until four years later.Second, since it usually takes sacrifice of both internal iliac arteries to cause permanent claudication, it is improbable that progression to moderate stenosis on the ipsilateral side would have been enough to tip the patient from normal to claudication.Third, even assuming the neointimal hyperplasia was sufficient, because claudication took four years to develop, the same four years provided ample time for the patient to compensate through collateralization.Finally, and most importantly, the severe l3-4 spinal canal stenosis likely caused neurogenic claudication.Implantation of three stent grafts inside a narrowed distal aorta reduced the left iliac endograft leg lumen to 5.6x6.9mm.The use of two left leg stents was likely intentional.If unplanned, a 13mm zsle stent sealing in the preexisting left cia stent would have been anticipated.The use of zsle-24-90 rather than a zsle 24-74 cannot be explained.A ridge caused by acute angulation of the ipsilateral bridging stent as it exited the ipsilateral gate exactly at the right cia ostium was a stimulus for neointimal hyperplasia formation.Had a zalb-24-84 been implanted, proximal right cia ipsilateral gate implantation would have eliminated the possibility by creating a smooth bridging stent gate transition.Based on the imaging review, there are many factors that contributed to the claudication rather than endograft leg stenosis.The contralateral leg lumen stenosis started at the completion of surgery due to the implantation of 3 grafts inside the already narrowed distal aorta.This would have likely led to claudication immediately but this was not reported until 4 years later when the patient¿s anatomy had time to compensate through collateralization.The instructions for use (ifu) for all of these products specifically states, pre-existing regions of stenosis/narrowing (less than approximately 20mm id in the aorta or 7 to 8 mm id in the iliacs have been shown to increase the risk of a thromboembolic event (e.G., graft limb occlusion).Each zenith device is shipped with instructions for use (ifu) listing the indications for use, contraindications, warnings and precautions, and the correct deployment procedure.Per the ifu: inspect the device and packaging to verify that no damage has occurred as a result of shipping.If damage has occurred, do not use the product and return to cook.Vessels that are significantly calcified, occlusive, tortuous or thrombus-lined may preclude placement of the endovascular graft and/or may increase the risk of embolization.As the sheath and/or wire guide is withdrawn, anatomy and graft position may change.Constantly monitor graft position and perform angiography to check position as necessary.The device history record was reviewed, for lot # 3771296 (finished assembly) and lot # fs3184579 (graft), no nonconformances related to the reported failure mode were noted.Based on the image review the likely cause of claudication reported is due to severe l3-4 spinal canal stenosis rather than bilateral endograft leg stenosis.Due to various facts, including: the contralateral leg stenosis was present immediately; however, claudication was not reported until four years.Secondly, the progression to moderate stenosis on the ipsilateral (right) side would not have caused claudication, as it usually takes sacrifice of both internal iliac arteries to cause claudication.Thirdly, even if neointimal hyperplasia was sufficient there was adequate time (four years) for the patient to compensate through collateralization.The distal aortic lumen diameter was 14.7x22mm four years after the implantation.The atherosclerotic distal abdominal aortic diameter was not aneurysmal and the distal aortic lumen diameter may have been more limited at implantation.The atherosclerotic condition would have caused reduction in the lumen diameter, increasing the risk of stenosis.The initial left zsle-11-39-zt was placed 16mm into the previously placed 45mm (13x45mm) stent extending from the zalb flow divider.The second left zsle-24-90-zt stent was implanted inside the zsle-11-39-zt, the contralateral gate and the previously placed 13mm.This narrowed the lumen to 5.6x9mm at edge of zsle-24-90-zt.Even if the left zsle-24-90 was not impinged on the internal iliac artery origin and could have been implanted 13mm more distal, the lumen would have still been 9mm inside the contralateral gate.Implantation of three stent grafts inside a narrowed distal aorta reduced the left iliac endograft lumen diameter.The use of two left stents was likely intentional, however, the use of zsle-24-90 rather than zsle-24-74 cannot be explained.Therefore, a possible root cause for stenosis is procedure related: patient condition related to occurrence.Per the quality engineering risk assessment, no further action is required.Monitoring will continue to be performed for similar complaints.The appropriate cook personnel have been notified of this event.

• Brand Name: ZENITH FLEX WITH SPIRAL-Z TECHNOLOGY AAA ENDOVASCULAR GRAFT ILIAC LEG
• Common Device Name: MIH SYSTEM, ENDOVASCULAR GRAFT, AORTIC ANEURYSM TREATMENT
• Manufacturer (Section D): COOK INC; 750 daniels way; bloomington IN 47404
• MDR Report Key: 7088730
• Report Number: 1820334-2017-04260
• Device Sequence Number: 1260356
• Product Code: MIH
• UDI-Device Identifier: 10827002552477
• UDI-Public: (01)10827002552477(17)151001(10)3771296
• Combination Product (Y/N): N
• PMA/510(K) Number: P020018
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Reporter Type: Manufacturer
• Report Source: company representative,foreig
• Initial Reporter Occupation: Physician
• Type of Report: Initial,Followup
• Report Date (Section B): 03/23/2018

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Is this an Adverse Event Report?: No
• Is this a Product Problem Report?: No
• Operator of Device: Health Professional
• Device Model Number: G55247
• Device Catalogue Number: ZSLE-24-90-ZT
• Was Device Available for Evaluation?: No
• Initial Date Received by Manufacturer: 11/17/2017
• Supplement Date Received by Manufacturer: 02/22/2018
• Initial Report FDA Received Date: 12/06/2017
• Supplement Report FDA Received Date: 03/23/2018
• Is This a Single-Use Device that was Reprocessed and Reused on a Patient? (Y/N): No
• Patient Sequence Number: 1
• Outcome Attributed to Adverse Event: Required Intervention