|
Investigation-evaluation: cook incorporated was notified that a patient had thrombosis of the right zenith flex with spiral-z technology aaa endovascular graft iliac leg (rpn: zsle-9-90-zt) five days after endovascular aortic repair (evar).The patient had medical history of hyperlipidemia, chronic obstructive pulmonary disease (copd), peripheral vascular disease (pvd), hypertension, and prior aortic surgery (evar).He quit smoking more than one year ago.Before the evar procedure, the patient was prescribed acetylsalicylic acid (asa) medication, a beta blocker, and a statin.At the time of the procedure, the patient was prescribed acetylsalicylic acid (asa).He underwent evar on (b)(6) 2024.The following cook grafts were implanted during the procedure: cook fenestrated proximal device (rpn: pre-loaded-fenestrated-prox ) zenith flex with spiral-z technology aaa endovascular graft iliac leg (rpn: zsle-16-56-zt) placed on the left.Zenith flex with spiral-z technology aaa endovascular graft iliac leg (rpn: zsle-16-90-zt) placed on the left.Zenith branch endovascular graft iliac bifurcation (rpn: zbis-12-61-41) placed on the left zenith flex with spiral-z technology aaa endovascular graft iliac leg (rpn: zsle-9-90-zt) placed on the right.The patient also received competitors stents in the superior mesenteric artery, right renal artery, and left renal artery.As planned during the procedure the femoral artery and iliac artery required dilation.Additionally, lumbar embolization and renal artery embolization were required.At the conclusion of the procedure, imaging was completed.All target vessels were patent and no endoleaks were present.At discharge, the patient was prescribed acetylsalicylic acid (asa), statin, beta blocker, clopidogrel, and lovenox.On (b)(6) 2023 (five days post procedure) it was discovered that the patient had " thrombosis of the right iliac leg" in the zenith flex with spiral-z technology aaa endovascular graft iliac leg (rpn: zsle-9-90-zt) placed on the right.A percutaneous thrombectomy was performed successfully on (b)(6) 2023) to treat the thrombosis.The patient experienced prolonged hospitalization due to the thrombosis in the right leg.The patient underwent imaging on (b)(6) 2023 (8 days post procedure), (b)(6) 2023 (179 days post procedure), and (b)(6) 2024 (204 days post procedure).All imaging showed that the stent grafts were all patent and no endoleaks were present.The focus of this report is the thrombosis of the zenith flex with spiral-z technology aaa endovascular graft iliac leg (rpn: zsle-9-90-zt) placed on the patient¿s right.Reviews of documentation including the complaint history, drawing, device history record (dhr), quality control, specifications, manufacturing instructions (mi), and instructions for use (ifu) of the device, were conducted during the investigation.The complaint device was not returned; therefore, no physical examinations could be performed.However, a document-based investigation evaluation was performed.A review of the device master record (dmr) concluded that sufficient inspection activities are in place to identify this failure mode prior to distribution.A review of the dhrs for the reported complaint device lot and the related subassembly lots revealed one related non-conformance in which one device was reworked and re-inspected prior to further processing.A complaint history search did not identify any other complaints for this device lot.It should be noted that this device is supplied via a one-device lot.Based on the available information, cook has concluded that the device was manufactured to specification and that there is no evidence suggesting nonconforming product exists either in house or in the field.Cook also reviewed product labeling.The ifu packaged with the device contains the following in relation to the reported failure mode: 4 warnings and precautions 4.1 general ¿ patients experiencing reduced blood flow through the graft limb and/or leaks may be required to undergo secondary interventions or surgical procedures.4.2 patient selection, treatment and follow-up ¿ zenith spiral-z 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.¿ adequate iliac or femoral access is required to introduce the device into the vasculature.Access vessel diameter (measured inner wall to inner wall) and morphology (minimal tortuosity, occlusive disease and/or calcification) should be compatible with vascular access techniques and delivery systems of a 14 french to 16 french vascular introducer sheath.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.A vascular conduit technique may be necessary to achieve success in some patients.¿ pre-existing regions of stenosis/narrowing (less than approximately 20 mm 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).The potential for this increased risk in these patients may preclude placement of an endovascular graft.Dilatation of these regions with a noncompliant balloon and/or stent placement may be necessary to help assure maintained graft patency and to reduce the risk of a thromboembolic event.Additionally, the completion angiogram (with stiff wire guide removed) should be reviewed carefully to determine if further treatment in these regions is necessary (e.G., adjunctive ballooning or stenting).Failure to remove the stiff wire guide prior to the angiogram could mask any limb kinking or narrowing that might occur when the wire guide is removed.¿ follow-up imaging should be carefully reviewed for narrowing with in the graft leg.Patients with a graft leg lumen of less than approximately 5 mm id may be at increased risk of a thromboembolic event (e.G., graft limb occlusion).Reintervention (e.G., noncompliant ballooning or stenting in these regions) should be considered to help assure maintained graft patency and to reduce the risk of a thromboembolic event.¿ patients with poor outflow or a hypercoagulable state (e.G., cancer) may be at an increased risk of a thromboembolic event.¿ the zenith spiral-z iliac leg with the z-trak introduction system is not recommended in patient who cannot tolerate contrast agents necessary for intraoperative and postoperative follow-up imaging.All patients should be monitored closely and checked periodically for a change in the condition of their disease and the integrity of the endoprosthesis.¿ 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 spiral-z aaa iliac leg.If contrast-enhanced spiral cta with 3-d reconstruction is not available, the patient should be referred to a facility with these capabilities.Lengths ¿ 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 postoperative follow-up.¿ after endovascular graft placement, patients should be regularly monitored for perigraft flow, aneurysm growth or changes in the structure position of the endovascular graft.At a minimum, annual imaging is required, including: 1) abdominal radiographs to examine device integrity (separation between components or stent fracture) 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.4.5 implant procedure ¿ 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.¿ inaccurate placement and/or incomplete sealing of the zenith spiral-z aaa iliac leg within the vessel may result in increased risk of endoleak, migration or inadvertent occlusion of the internal iliac arteries.¿ 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.¿ excessive overlap 10 mm above the main body bifurcation may increase the risk of limb thrombosis.5.2 potential adverse events ¿ claudication (e.G., buttock, lower limb) ¿ endoprosthesis: improper component placement; incomplete component deployment; component migration; component separation from another graft component; suture break; occlusion; infection; stent fracture; graft material wear; dilatation; erosion; puncture; perigraft flow; and corrosion ¿ graft or native vessel occlusion ¿ surgical conversion to open repair.7.1 individualization of treatment additional considerations for patient selection include, but are not limited to: ¿ patient¿s age and life expectancy ¿ co-morbidities (e.G., cardiac, pulmonary, or renal insufficiency prior to surgery, morbid obesity) ¿ patient¿s suitability for open surgical repair ¿ patient¿s ability to tolerate general, regional, or local anesthesia.¿ iliofemoral access vessel size and morphology (minimal thrombus, calcification and/or tortuosity) should be compatible with vascular access techniques and accessories of the delivery profile of a 14 french to 16 french vascular introducer sheath.¿ freedom from significant femoral/iliac artery occlusive disease that would impede flow through the endovascular graft.8 patient counseling information ¿ 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 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 is required and should be considered a life-long commitment to the patient¿s health and well-being.¿ physicians must advise all patients that it is important to seek prompt medical attention if they experience signs of limb occlusion, aneurysm enlargement or rupture.Signs of graft limb occlusion include pain in the hip(s) or leg(s) during walking or at rest or discoloration or coolness of the leg.Aneurysm rupture may be asymptomatic, but usually presents as: pain; numbness; weakness in the legs; any back, chest, abdominal or groin pain; dizziness; fainting; rapid heartbeat or sudden weakness.Physicians should refer patients to the patient guide regarding risks occurring during or after implantation of the device.Procedure-related risks 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 visits additional health practitioners, particularly for any additional diagnostic procedures (e.G., mri).11 directions for use ¿ iliofemoral access vessel size and morphology (minimal thrombus, calcium and/or tortuosity) should be compatible with vascular access techniques and accessories.Arterial conduit techniques may be required.12 imaging guidelines and postoperative follow-up 12.1 general ¿ the long-term performance of endovascular grafts with secondary endovascular intervention using additional components 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 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 an individual basis and prescribe follow-up relative to the needs and circumstances of each individual patient.The minimum requirement for patient follow-up (described in the instructions for use for the zenith aaa device that was used) should be maintained even in the absence of clinical symptoms (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.¿ duplex ultrasound imaging may provide information on aneurysm diameter change, endoleak, patency, tortuosity, and progressive disease.¿ imaging was provided for the investigation.The image reviewer noted ¿this consists of a pre-procedure ct scan from (b)(6) 2022, and shows a previous evar, as well as what looks like some sort of extended graft down the r.Iliac artery as far as just above the groin.There appears to be a suture line there, where it is anastomosed to the distal external iliac artery just before it becomes the common femoral artery.There is also a lot of heavy calcifications of the old aneurysm sac, which makes visualization of the endograft very difficult.The patient has also had spinal surgery with some lumbar rods inserted bilaterally, which also contribute to the difficulty in seeing things properly.The r.Internal iliac has been excluded by the presumed r.External iliac graft, as well as what appears to be multiple coils in the internal iliac artery.The l.Internal iliac is patent but heavily calcified.We also have some selected angio runs from the procedure performed on the (b)(6) 2023 (9 months after the ct scan) and this imaging consists of 5 brief angio runs, and a cone beam ct at the end of the procedure.Again, good visualization is difficult due to all the calcification, coils, and lumbar spinal rods.These images show good cannulation of both renal arteries, and the sma, along with a good deployment of the zbis on the left side.There is no imaging specifically of the right iliac graft components or the external iliac, although both iliac limbs can be partially seen on the cone beam ct.There is no evidence of any kinking or compression in the parts that can be seen.We also have a duplex ultrasound scan ¿ two selected runs ¿ done 5 days post-procedure, which confirms the occlusion of the right iliac limb of the endograft.This was treated by secondary endovascular means, including percutaneous thrombectomy, which was successful.Subsequent follow-up imaging out to 204 days showed all graft components patent and no endoleaks.The cause of the apparently spontaneous thrombosis of the r.Iliac graft limb remains unknown.There are no obvious kinks or compression on the few bits of imaging where that graft component is visible.However, the patient had a lot of foreign material including previous evar, new fevar, zbis, multiple (lots) of coils, lumbar spinal rods, and probably a previous r.External iliac graft (not a stent graft ¿ a plain graft), so may well have been pro-thrombotic.It could be classified as a procedural complication in a patient who was predisposed to thrombosis due to multiple foreign bodies, previous surgery, and possibly ineffective anti-platelet meds.¿ an imaging report was provided by the site and indicated the angiography of the occluded right limb showed folding of the iliac limb.That imaging was not provided by the site for the investigation.The image reviewer concluded based on imaging provided and the image report of the site that this event ¿could be classified as a procedural complication in a patient who was predisposed to thrombosis due to multiple foreign bodies, previous surgery, and possibly ineffective anti-platelet meds.¿ based on the information provided, no product returned, and the results of the investigation, a definitive cause for the failure could not be established.A potential root cause has been traced to patient condition or medial procedure.The image reviewer stated, ¿the cause of the apparently spontaneous thrombosis of the right iliac graft limb remains unknown.There are no obvious kinks or compression on the few bits of imaging where that graft component is visible.However, the patient had a lot of foreign material including previous evar, new fevar, zbis, multiple (lots) of coils, lumbar spinal rods, and probably a previous right external iliac graft (not a stent graft ¿ a plain graft), so may well have been pro-thrombotic.If we can find out if they¿d been taking anti-platelet medications or not during those 5 days post-op, that may give us a clue as to why thrombosis occurred.However, i don¿t consider this to be a fault or failure of the endograft components.It could be classified as a procedural complication in a patient who was predisposed to thrombosis due to multiple foreign bodies, previous surgery, and possibly ineffective anti-platelet meds.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 or that a death or serious injury occurred; nor is it admission that any cook device caused, contributed to, or is likely to cause or contribute to a death or serious injury if a malfunction occurred.
|
