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In december 2020, cook received a literature article titled "long-term outcomes of endovascular aortic aneurysm repair with the zenith aaa endovascular graft: a single-center study" published online in the japanese journal of radiology in october 2019.The purpose of the article was to present a retrospective study for the long-term results obtained with endovascular abdominal aortic aneurysm (aaa) repair (evar) using the zenith aaa endovascular graft from a single institution.Between august 2007 and december 2013, 95 consecutive patients underwent evar using the zenith aaa endograft at a single institution encompassing three university hospitals.Eighty-one patients were male, 14 were female, and the median age was (b)(6) (range 51¿95) years old.The standard indication for evar included an aaa larger than 5 cm, or patients with a smaller aaa but with iliac aneurysms larger than 3 cm in maximum diameter.A rapidly increasing aaa sac diameter of more than 5 mm within 6 months and symptomatic aaa in emergency treatment were also included.All patients were at high risk for open repair because of their comorbidities or high age, and had suitable anatomy for a zenith aaa endovascular graft.Evar was performed in some patients who had exclusion-criteria anatomy, although the physicians essentially complied with the instructions for use (ifu).Anatomic exclusion criteria included a proximal neck length < 15 mm, a proximal neck diameter > 32 mm or < 18 mm, a neck angle > 60 degrees, and an angle between the neck and aaa > 45 degrees.The zenith endovascular graft used in the procedures consists of a three modular system composed by a bifurcated aortic main body with suprarenal bare stent aortic fixation and two iliac legs.The zenith had minor unspecified modifications, and the second-generation zenith flex aortic main body was used from july 2010.All patients received general anesthesia, and surgical access was via the femoral arteries.The internal iliac arteries were embolized if there were coexisting common or internal iliac artery aneurysms or the common iliac arteries were unstable for distal landing zones.Although we did not routinely embolize branch arteries, such as inferior mesenteric arteries (ima), lumbar arteries, or accessory renal arteries, under certain criteria, some branch arteries with markedly large diameters were embolized based on the operator¿s decision to prevent type 2 endoleaks.These embolizations were performed just before the stent-graft placement during the same evar procedure.The follow-up imaging protocol included non-enhanced, arterial, and delayed venous phase contrast-enhanced aortoiliac computed tomography (ct) at 1 week, 6 months, and 1 year after the procedures and annually thereafter.This report covers a type 3 endoleak that was observed in one patient.The endoleak disappeared spontaneously during follow-up.Kawamata, h., tajima, h., ueda, t.Et al.Long-term outcomes of endovascular aortic aneurysm repair with the zenith aaa endovascular graft: a single-center study.Jpn j radiol 38, 77¿84 (2020).Https://doi.Org/10.1007/s11604-019-00892-6.
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On (b)(6) 2020, cook became aware of a published journal article describing the experiences of a facility in japan in use of zenith aaa endovascular grafts.The article appeared in the japanese journal of radiology and was published on (b)(6) 2019 (https://doi.Org/10.1007/s11604-019-00892-6).In the article, ¿long-term outcomes of endovascular aortic aneurysm repair with the zenith aaa endovascular graft: a single-center study,¿ the authors describe their experiences in using zenith flex aaa endovascular grafts.This event concerns a reported adverse event that a type 3 endoleak was observed in one patient.The type 3 endoleak was reportedly resolved spontaneously during follow up.A review of the complaint history, instructions for use (ifu), quality control, and specifications of the device was 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 design history file (dhf) showed that this device is both safe and effective for its intended use.A review of the device history record (dhr) was unable to be completed due to a lack of lot information from the user facility.It should be noted that this device is distributed via a one-device lot.Based on the available information, cook has concluded that there is no evidence suggesting nonconforming product exists either in house or in field.Cook also reviewed product labeling.The current product instructions for use (ifu), [t_zaaaf_rev5] ¿zenith flex® aaa endovascular graft with the z-trak¿ introduction system¿, provides the following information to the user related to the reported failure mode: ¿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 in 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 requirements are critical to the performance of the endovascular repair.¿ key anatomical elements that may affect successful exclusion of the aneurysm include severe 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.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.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 ¿ appropriate procedural imaging is required to successfully position the zenith flex aaa endovascular graft and assure accurate apposition to the aortic wall.¿ 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.¿ inadequate fixation of the zenith flex aaa endovascular graft may result in increased risk of migration of the stent graft.Incorrect deployment or migration of the endoprosthesis may require surgical intervention.4.6 molding balloon use ¿ use care in inflating the balloon within the graft in the presence of calcification as excessive inflation ma cause damage to the vessel.5 adverse events 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 ¿ endoleak ¿ endoprosthesis: improper component placement; component migration 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 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.Device-related risks include occlusion, endoleak, aneurysm enlargement, fracture, potential for reintervention and open surgical conversion, rupture, and death.11 directions for use 11.1 bifurcated system 11.1.12 molding balloon insertion 5.Expand the molding balloon with diluted contrast media (as directed by the manufacturer) in the area of the most proximal covered stent and the infrarenal neck, starting proximally and working in the distal direction.Final angiogram 1.Position angiographic catheter just above the levels of the renal arteries.Perform angiography to verify that the renal arteries are patent and that there are no endoleaks.Verify patency of internal iliac arteries.2.Confirm there are no endoleaks or kinks and verify position of proximal gold radiopaque markers.Remove the sheaths, wires and catheters.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 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 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 requirements for patient follow-up (described in the instructions for use for the zenith flex aaa endovascular graft) 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.12.6 additional surveillance and treatment additional surveillance and possible treatment is recommended for: ¿ aneurysms with type iii endoleak consideration for reintervention or conversion to open repair should include the attending physician¿s assessment of an individual patient¿s comorbidities, life expectancy and the patient¿s personal choices.Patients should be counseled that subsequent reinterventions including catheter based and open surgical conversion are possible following endograft placement." based on the information provided, no product returned, and the results of our investigation, a definitive root cause for this event was unable to be established.However, endoleaks are a known inherent risk of using this device.The appropriate personnel have been notified.Cook will continue to monitor for similar complaints.Per the quality engineering risk assessment no further action is required.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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