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	G55229
Medical Device Problem Code	Occlusion Within Device (1423)
Health Effect - Clinical Codes	Thrombus (2101); Stenosis (2263); No Code Available (3191)
Date of Event	11/24/2017
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 receipt of additional information or completion of the investigation.
Event or Problem Description
The user facility reported a male patient with an abdominal aortic aneurysm (aaa) underwent an endovascular aneurysm repair (evar) on (b)(6) 2017.As reported, the patient was implanted with a zenith flex aaa endovascular graft bifurcated main body graft and two zenith¿ spiral-z¿ aaa iliac legs; a contralateral leg (zsle-11-122-zt) and an ipsilateral leg (zsle-16-56-zt) with no problems occurring.On (b)(6) 2017, the patient complained of coldness of the lower legs, so an ankle brachial index (abi) test was performed.The abi level reading was 0.4.The level right after the evar was 1.0.A computerized tomography (ct) scan was performed and found clots inside the contralateral leg graft (zsle-11-122-zt) near the bifurcation of the external iliac artery and the internal iliac artery.Because of stenosis due to the clots, the physician planned removal of the clots and endovenous laser treatment (evt) the next day, and administered one tablet of plavix (antiplatelet drug).On (b)(6) 2017, the abi level had increased to 0.8 before performing angiography, the clots appeared to be dissolved on the angiographic image, and the percentage of stenosis was 70%.Due to this improvement tendency, no more intervention was considered, but placement of another manufacturer¿s stent in the contralateral leg graft at the external iliac artery was performed because it was likely the clots dissolved due to the efficacy of plavix (antiplatelet drug).After placement of another manufacturer's stent, the pulse of the lower leg became tactual.It was reported that the patient is doing fine.
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 provided imaging, the device history record, instructions for use, manufacturing instructions, and quality control data was conducted.Select implantation angiography images, a two-week post implantation computerized tomographic angiography (cta) and select images of the 15 days post implantation secondary intervention were provided.Severe stenosis caused by thrombus in the distal left zsle is confirmed.The risk of thrombus formation was increased by a narrow distal aorta, longitudinal compression of the zsle in the external iliac artery (eia), and a patient specific tendency to form thrombus on the graft material.Significant findings relative to the patient's anatomy were observed.The distal aorta was narrow.Significant findings relative to the disease state were observed.The patient displayed an increased tendency to form thrombus on the graft fabric.Significant findings relative to the use of the device were observed.The zsle 11-122 was implanted with 10 mm of longitudinal compression in the left eia segment.Fabric redundancy created by the compression increased the risk of thrombus formation.Significant findings relative to the design or performance of the device were observed.Mural thrombus formation caused severe left zsle stenosis and moderate right zsle stenosis.Cause of adverse events was not observed.The image review confirmed the presence of severe stenosis causing thrombus in the distal left zsle.Each zenith device is shipped with instructions for use (ifu) listing the indications for use, contraindications, warnings and precautions, and the correct deployment procedure.Thrombosis can occur for a variety of reasons, such as genetic predisposition, iliac tortuosity, external compression, stenosis, improper overlap, narrow inner iliac lumen, vessel damage, and rough surfaces.Tortuosity, compression, and pulsation can create high shear forces within the leg that stimulate thrombus growth.Where a small thrombus has formed, the clot can enlarge because the blood flow slows around the clot, allowing clot-forming elements to be deposited.Pulsation and a small inner lumen can occur through graft oversizing or undersizing.A contributing factor to this complaint was patient anatomy because the distal aorta was narrow.At implantation balloon angioplasty expanded the distal aorta from the flow divider through the aortic bifurcation 25 mm right to left, but as soon as the balloons were deflated the aorta recoiled.This resulted in the narrowing of the lumen to 15 mm x 19 mm at the flow divider and 12.5 mm x 20 mm at the aortic bifurcation on the subsequent cta.Narrowing of the distal aorta would have decreased the diameter of the inner iliac lumen creating high shear forces as well as fabric redundancy resulting in an increased risk of thrombus formation.Evidence of longitudinal compression in the left eia segment of the zsle was noted in the image review.The left contralateral zsle-11-122 was implanted in the left eia to a length of 112 mm.Based on the spacing of the zsle spirals, it was evident that the longitudinal compression occurred in the left eia segment of the zsle.This 10 mm of longitudinal compression would have created fabric redundancy which increases the risk of thrombus formation.The patient displayed an increased tendency to form thrombus on the graft fabric.Image review reported thrombus on the left zsle (severe - 70% stenosis), right zsle (moderate - 50% stenosis) and main body (thin layer coated fabric).This complaint has been confirmed based on the image review findings.After review of the device history record, design history files and image review, there is no evidence to suggest that the device was manufactured out of specifications.Contributing factors to the thrombus formation are the patient's increased propensity to form thrombus on the graft fabric, narrowed distal aorta, and 10 mm of longitudinal compression in the left contralateral eia segment.The root cause for the reported event is likely procedure related ¿ patient condition related to occurrence.Measures have been initiated to address this failure mode.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: 7128114
• Report Number: 1820334-2017-04266
• Device Sequence Number: 11298973
• Product Code: MIH
• UDI-Device Identifier: 10827002552293
• UDI-Public: (01)10827002552293(17)201002(10)8235280
• Combination Product (Y/N): N
• PMA/510(K) Number: P020018
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2017
• Reporter Type: Manufacturer
• Report Source: foreign,health professional,u
• Initial Reporter Occupation: Physician
• Type of Report: Initial,Followup
• Report Date (Section B): 04/16/2018

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: G55229
• Device Catalogue Number: ZSLE-11-122-ZT
• Was Device Available for Evaluation?: No
• Initial Date Received by Manufacturer: 11/24/2017
• Supplement Date Received by Manufacturer: 04/05/2018
• Initial Report FDA Received Date: 12/19/2017
• Supplement Report FDA Received Date: 04/16/2018
• 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