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Investigation ¿ evaluation: cook became aware on 04nov2021 of an event with a 75-year-old male patient.The complaint device was a zenith flex aaa endovascular graft (rpn: tffb-30-96-zt, lot 3816934), originally implanted (b)(6) 2013.The patient was compliant with protocols per the ifu since the initial placement of the graft.The patient was undergoing a ct scan on (b)(6) 2021 at hospital (b)(6) and it appeared that the suprarenal stent detached from the main body graft.The physician performed an additional procedure implanting a fenestrated graft to repair the issue.It was reported that the patient died three days after the procedure from a massive heart attack.The patient had a history of coronary heart disease.Reviews of the documentation including the complaint history, device history record, drawing, instructions for use (ifu), manufacturing instructions, quality control procedures and specifications of the device, were conducted during the investigation.The complaint device was not returned for evaluation; therefore, no physical examination could be conducted.However, medical imaging was provided for expert image review.Suprarenal and sealing stent separation discovered nine years after implantation was confirmed.Separation risk factors include absent seal zone apposition by the sealing stent and mainbody and iliac leg tortuosity.The sealing stent had lost all seal zone wall support, as it had been completely engulfed by the aneurysm.This was likely the single greatest stressor on the sealing to suprarenal stent sutures.The stress of the sutures was also increased by a likely circuitous mainbody and iliac leg path through the aneurysm.Simulating a path through the sac would have accommodated the mainbody and the distal components indicated that the original path could not have been straight, most likely bowing anterior and rightward.Aneurysm engulfment of the proximal seal zone was intrinsic to the aneurysm neck and proximal seal zone.Distal endoleaks were absent and the type 2 endoleak was very minor.Aneurysm erosion into the l2 and l3 lumbar vertebral bodies indicates that the proximal aneurysm had been much larger than the seal stent for a long time.Either the aneurysm began to engulf the sealing stent soon after implantation or the seal zone was originally outside the ifu.Additionally, a document-based investigation evaluation was performed.A review of the device master record (dmr) concluded appropriate inspections are in place relative to the reported device failure.A review of the device history record (dhr) for lot 3816934, graft subassembly lot fs3045537, graft kit lot fs2637849 found no nonconformances that could have contributed to the reported failure mode.The graft subassembly lot 1130259.3 was sewn by approved vendor sei medical s.A.Upon incoming inspection, zero nonconformance¿s were detected.It should be noted that there were no other complaints associated with the final product lot.Cook also reviewed product labeling.The device was packaged with ifu t_zaaaf_rev4.The ifu includes the following, warnings, precautions, and instructions for proper placement of the device.4.Warnings and precautions: 4.1 general: additional endovascular interventions or conversion to standard open surgical repair following initial endovascular repair should be considered for patients experiencing an enlarging aneurysm, unacceptable decrease in fixation length (vessel and component overlap) and/or endoleak.An increase in aneurysm size and/or persistent endoleak or migration may lead to aneurysm rupture.4.2 patient selection, treatment and follow-up: the zenith flex aaa endovascular graft is designed to treat aortic neck diameters no smaller than 18 mm and no larger than 32 mm.The zenith flex aaa endovascular graft is designed to treat proximal aortic necks (distal to the lowest renal artery) of at least 15 mm length.Iliac artery distal fixation site greater than 10 mm in length and 7.5 ¿ 20 mm in diameter (measured outer wall to outer wall) is required.These sizing measurements are critical to the performance of the endovascular repair.Key anatomical elements that may affect successful exclusion of the aneurysm include sever proximal neck angulation (>60 degrees for infrarenal neck to axis of aaa or >45 degrees for suprarenal neck relative to the immediate infrarenal neck); short proximal aortic neck (<15 mm); an inverted funnel shape (greater than 10% increase in diameter over 15 mm of proximal aortic neck length); and circumferential thrombus and/or calcification at the arterial implantation sites, specifically the proximal aortic neck and distal iliac artery interface.In the presence of anatomical limitations, a longer neck may be required to obtain adequate sealing and fixation.Irregular calcification and/or plaque may compromise the attachment and sealing at the fixation sites.Necks exhibiting these key anatomical elements may be more conducive to graft migration or endoleak.Multiple large, patent lumbar arteries, mural thrombus and a patent inferior mesenteric artery may all predispose a patient to type ii endoleaks.Patients with uncorrectable coagulopathy may also have an increased risk of type ii endoleak or bleeding complications.Successful patient selection requires specific imaging and accurate measurements; please see section 4.3 pre-procedure measurement techniques and imaging.4.3 pre-procedure measurement techniques and imaging: clinical experience indicates that contrast-enhanced spiral computed tomographic angiography (cta) with 3-d reconstruction is the strongly recommended imaging modality to accurately assess patient anatomy prior to treatment with the zenith flex aaa endovascular graft.If contrast-enhanced spiral cta with 3-d reconstruction is not available, the patient should be referred to a facility with these capabilities.Lengths: the long-term performance of endovascular grafts has not yet been established.All patients should be advised that endovascular treatment requires life-long, regular follow-up to assess their health and the performance of their endovascular graft.Patients with specific clinical findings (e.G., endoleaks, enlarging aneurysm or changes in the structure or position of the endovascular graft) should receive enhanced follow-up.Specific follow-up guidelines are described in section 12, imaging guidelines and postoprative follow-up.After endovascular graft placement, patients should be regularly monitored for perigraft flow, aneurysm growth or changes in the structure or position of the endovascular graft.At a minimum, annual imaging is required, including: 1) abdominal radiographs to examine device integrity (separation between components, stent fracture or barb separation) and 2) contrast and non-contrast ct to examine aneurysm changes, perigraft flow, patency, tortuosity, and progressive disease.If renal complications or other factors preclude the use of image contrast media, abdominal radiographs and duplex ultrasound may provide similar information.4.4 device selection: strict adherence to the zenith flex aaa endovascular graft ifu sizing guide is strongly recommended when selecting the appropriate device size (tables 10.5.1 through 10.5.2).Appropriate device oversizing has been incorporated into the ifu sizing guide.Sizing outside of this range can result in endoleak, fracture, migration, device infolding or compression.4.5 implant procedure: do not bend or kink the delivery system.Doing so may cause damage to the delivery system and the zenith flex aaa endovascular graft.Do not continue advancing any portion of the delivery system if resistance is felt during advancement of the wire guide or delivery system.Stop and assess the cause of resistance; vessel, catheter or graft damage may occur.Exercise particular care in areas of stenosis, intravascular thrombosis or in calcified or tortuous vessels.Repositioning the stent graft distally after partial deployment of the covered proximal stent may result in damage to the stent graft and/or vessel injury.Inaccurate placement and/or incomplete sealing of the zenith flex aaa endovascular graft within the vessel may result in increased risk of endoleak, migration or inadvertent occlusion of the renal or internal iliac arteries.Renal artery patency must be maintained to prevent/reduce the risk of renal failure and subsequent complications.Fluoroscopy should be used during introduction and deployment to confirm proper operation of the delivery system components, proper placement of the graft, and desired procedural outcome.The zenith flex aaa endovascular graft incorporates a suprarenal stent with fixation barbs.Exercise extreme caution when manipulating interventional and angiographic devices in the region of the suprarenal stent.Before deployment of the suprarenal stent, verify that the position of the access wire guide extends just distal to the aortic arch.4.6 molding balloon use: confirm complete deflation of the balloon prior to repositioning.5 adverse events: 5.2 potential adverse events: aneurysm enlargement, claudication (e.G., buttock, lower limb), endoleak, endoprosthesis: improper component placement; incomplete component deployment; component migration; suture break; occlusion; infection; stent fracture; graft material wear; dilatation; erosion; puncture; perigraft flow; barb separation and corrosion.8 patient counseling information: the long-term performance of endovascular grafts has not yet been established.All patients should be advised that endovascular treatment requires lifelong, regular follow-up to assess their health and the performance of their endovascular graft.Patients with specific clinical findings (e.G., endoleaks, enlarging aneurysms or changes in the structure or position of the endovascular graft) should receive enhanced follow-up.Specific follow-up guidelines are described in section 12, imaging guidelines and postoperative follow-up.Patients should be counseled on the importance of adhering to the follow-up schedule, both during the first year and at yearly intervals thereafter.Patients should be told that regular and consistent follow-up is a critical part of ensuring the ongoing safety and effectiveness of endovascular treatment of aaas.At a minimum, annual imaging and adherence to routine postoperative follow-up requirements are required and should be considered a lifelong commitment to the patient¿s health and well-being.Physicians should refer patients to the patient guide regarding risks occurring during or after implantation of the device.Procedure-related risk include cardiac, pulmonary, neurologic, bowel and bleeding complications.Device-related risks include occlusion, endoleak, aneurysm enlargement, fracture, potential for reintervention and open surgical conversion, rupture and death (see section 5.1, observed adverse events and section 5.2, potential adverse events).The physician should complete the patient i.D.Card and give it to the patient so that he/she can carry it with him/her at all times.The patient should refer to the card anytime he/she visit additional health practitioners, particularly for any additional diagnostic procedures (e.G., mri).12 imaging guidelines and postoperative follow-up: 12.1 general: the long-term performance of endovascular grafts has not yet been established.All patients should be advised that endovascular treatment requires lifelong, regular follow-up to assess their health and performance of their endovascular graft.Patients with specific clinical findings (e.G., endoleaks, enlarging aneurysms or changes in the structure or position of the endovascular graft) should receive additional follow-up.Patients should be counseled on the importance of adhering to the follow-up schedule, both during the first year and at yearly intervals thereafter.Patients should be told that regular and consistent follow-up is a critical part of ensuring the ongoing safety and effectiveness of endovascular treatment of aaas.Physicians should evaluate patients on and individual basis and prescribe their follow-up relative to the needs and circumstances of each individual patient.The recommended imaging schedule is presented in table 12.1.1 this schedule was used in the pivotal trial and is recommended even in the absence of clinical findings (e.G., pain, numbness, weakness).Patients with specific clinical findings (e.G., endoleaks, enlarging aneurysms or changes in the structure or position of the stent graft) should receive follow-up at more frequent intervals.The combination of contrast and non-contrast ct imaging provides information on aneurysm diameter change, endoleak, patency, tortuosity, progressive disease, fixation length and other morphological changes.The abdominal radiographs provide information on device integrity (separation between components, stent fracture and barb separation).Duplex ultrasound imaging may provide information on aneurysm diameter change, endoleak, patency, tortuosity and progressive disease.In this circumstance, a non-contrast ct should be performed to use in conjunction with the ultrasound.Ultrasound may be a less reliable and sensitive diagnostic method compared to ct.12.6 additional surveillance and treatment: aneurysms with type i endoleak, aneurysms with type iii endoleak, migration.After review of the ifu, cook has concluded the device labeling contains appropriate warnings, precautions and instructions to the user related to the reported failure.Evidence provided by the complaint facility, device failure analysis, device history record, complaint history, manufacturing documents, and verification testing, suggests that the device was manufactured to specification.There is no evidence of nonconforming devices from the complaint lot in house or in the field.Based on the information provided, no returned product and the results of our investigation, a definitive cause for the failure could not be established.While the cause in this case is not known, it is possible that the patient anatomy may have contributed to this incident.The appropriate personnel have been notified.Per the risk assessment no further action is required.We will continue to monitor for similar complaints.This report is required by the fda under 21 cfr part 803 and is based on unconfirmed information submitted by others.Neither the submission of this report nor any statement contained herein is intended to be an admission that any cook device is defective or malfunctioned, that a death or serious injury occurred, nor that any cook device caused, contributed to, or is likely to cause or contribute to a death or serious injury if a malfunction occurred.
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