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Investigation-evaluation cook identified an occlusion of the zenith flex with spiral-z technology aaa endovascular graft iliac leg during the investigation for a suprarenal stent separation on a cook zenith low profile aaa endovascular graft main body.The patient had a computed tomography (ct) scan completed for planning and sizing for an upcoming evar on (b)(6) 2014.He underwent an endovascular aortic repair (evar) on (b)(6) 2015 where cook devices were implanted.The patient was compliant with post operative follow up.Eight years after the index the procedure (date unknown), the patient was symptomatic and required hospital admission.It was discovered that the suprarenal stent on the cook main body graft had detached from the fabric of the main body graft.During the manufacturer's investigation into the suprarenal stent separation, imaging was provided.The imaging was reviewed and indicated complete occlusion of the left zenith flex with spiral-z technology aaa endovascular graft iliac leg.There appeared to be progressive disease of the aneurysm and thrombus was present in the aortic neck.The customer reported that the patient would require an aortic cuff to address the separation.It is expected that the occluded iliac leg will be treated when the aortic cuff is placed.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.Additionally, 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 dhr for the reported complaint device lot revealed no recorded non-conformances relevant to the failure mode.A complaint history search did not identify any other lot related complaints.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: 4.1 general ¿ additional endovascular interventions or conversion to standard open surgical repair following initial endovascular repair should be considered for patients experiencing enlarging aneurysms, unacceptable decrease in fixation length (vessel and component overlap) and/or endoleak.An increase in aneurysms, size and/or persistent endoleak or migration may lead to aneurysm rupture.¿ 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 sire 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 guides 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 within the leg graft.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 aaa iliac leg with the z-trak introduction system is not recommended in patients 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.¿ inability to maintain patency of at least one internal iliac artery or occlusion of an indispensable inferior mesenteric artery may increase the risk of pelvic/bowel ischemia 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.4.5 implant procedure ¿ inaccurate placement and/or incomplete sealing of the zenith spiral-z endovascular aaa iliac leg within the vessel may result in increased risk of endoleak, migration or inadvertent occlusion of the internal iliac arteries ¿ excessive overlap 10mm above the main body bifurcation may increase the risk of limb thrombosis.5.2 potential adverse events adverse events that may occur and/or require intervention include, but are not limited to: ¿ aortic damage, including perforation, dissection, bleeding, rupture and death.¿ arterial or venous thrombosis and/or pseudoaneurysm.¿ endoprosthesis: improper component placement; incomplete component deployment; component migration; component separation from another graft component/ suture break; occlusion; infection; stent fracture; graft material wear; dilation; erosion; puncture; peri graft flow; and corrosion.¿ graft or native vessel occlusion.¿ renal complications and subsequent attendant problems (e.G., dehiscence, infection) ¿ vessel damage.7.1 individualization of treatment the risks and benefits should be carefully considered for each patient before use of the zenith spiral-z aaa iliac leg.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 anatomical suitability for endovascular repair.¿ the risk of aneurysm rupture compared to the risk of treatment with zenith spiral-z aaa iliac leg.¿ 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 ¿ zenith spiral-z iliac artery distal fixation site greater than 10 mm in length and 7.5-20mm in diameter (measured outer wall to outer wall).¿ freedom from significant femoral/iliac artery occlusive disease that would impede flow through the endovascular graft.The final treatment decision is at the discretion of the physician and patient.8 patient counseling information: in addition to the risks and benefits of an endovascular repair, the physician should assess the patient¿s commitment and compliance to postoperative follow-up as necessary to ensure continuing safe and effective results.Listed below are additional topics to discuss with the patient as to expectations after an endovascular repair: ¿ 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.¿ 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 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.Imaging was provided for the investigation.The imaging was reviewed, and the reviewer concluded the following: ¿impression: 1.An infrarenal aaa is repaired using a zalb-24-118 main body graft, an ipsilateral zsle13-90 leg on the right, and a contralateral zsle-24-74 leg on the left.2.At 8 years postop, there is complete separation of the proximal zalb graft from the suprarenal stent.The proximal graft has migrated 14 mm distal to the suprarenal stent with loss of graft wall apposition but no endoleak is seen around the graft.3.The cause of the component separation cannot be determined from the imaging provided.However, the proximal neck length is only 12 mm on preop imaging and is outside the ifu for repair with this device.The suprarenal stent is positioned 2 mm below the rra, so the proximal graft would have had 10 mm or less of graft wall apposition.Combined with the aortic tortuosity and 48-degree angulation at the mid infrarenal segment, this may have led to shearing force at the junction of the suprarenal stent and minimally seated (wall apposed) proximal graft segment.4.There is a thin layer of focal posterior mural thrombus at 12 mm below the rra on preop imaging, but this was unlikely to be a contributing factor to the component separation as it is minimal in burden and no thrombus is seen in the rest of the neck proximal to this where the suprarenal stent junction would be positioned.5.Also at 8 years, there is complete occlusion of the left zsle leg graft with moderate mural thrombus in the zalb graft.There is severe tortuosity of the left cia on preop imaging resulting in 82-degree angulation at the mid leg graft.The aortic angulation on preop imaging also results in a significant 70-degree angulation at the mid zalb graft immediately above the proximal edge of the left zsle leg, which likely caused turbulent flow at the zsle origin.Finally, the left leg is positioned 16 mm above the flow divider.The ifu warns: ¿excessive overlap 10 mm above the main body graft bifurcation may increase the risk of limb thrombosis." all these findings likely contributed to the left zsle leg occlusion.¿ based on the information provided, no product returned, and the results of the investigation a definitive root cause for this event could not be established.Cook has determined patient anatomy was a likely contributing factor to the thrombus formation.The appropriate personnel have been notified.Cook will continue to monitor for similar complaints.Per the risk assessment no further action is required.This report includes information known at this time.A follow-up report will be submitted should additional relevant information become available.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.
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