|
Description of event according to article: following 2 unsuccessful retrieval attempts, 3 months after filter deployment, it was decided to leave the filter in place.4 years later the patient presented with left flank pain and gross hematuria.Ct and further venagraphy showed filter limb penetration of the overlying horseshoe kidney isthmus.The filter was tilted, with the proximal retrieval hook abutting into the vena cava wall at a point opposite to the right-sided origin of the middle renal vein draining the isthmus, with the right and left renal veins superiorly.The right renal artery passed anterior to the ivc, inferior to the middle renled to leverage the hook off the caval wall.The procedure was abandoned after a filter limb fractured and could not be located.4 days later the patient underwent open retrieval.After retraction of the right renal artery, caval control above and below the level of the renal isthmus, and looping of the renal veins, a 3-cm longitudinal venotomy was made.The retrieval hook was incorporated over a 1.5-cm length within the posteromedial caval wall.The hook was dissected out, and an attempt to collapse the filter through a 16f sheath failed.Using traction on a limb, we were able to deliver the filter, which was clogged with fresh thrombus.A 6f fogarty balloon successfully retrieved a fresh thrombus, with restoration of venous flow.Renal vein cross-clamp time was 26 minutes.After closure, an anticoagulant infusion was continued and switched to therapeutic-dose of a different anticoagulant 24 hours later.Postoperative ct of the chest did not locate the dislodged filter limb.The patient was discharged home 4 days later with a 3-month prescription for an anticoagulant.Patient outcome: at 2 months of follow-up, the patient was well with no further hematuria.
|
|
Manufacturers ref# (b)(4).Summary of investigational findings: the investigation is based on the article and a review of the contained figures.One figure in the article demonstrates a horseshoe kidney draped anterior to the ivc and aorta.Within the ivc there are multiple metallic tines consistent with clinical history of a celect ivc filter.One primary filter leg appears to demonstrate a grade 3 interaction with the wall of the ivc, extending into the parenchyma of the horseshoe kidney.Another primary leg appears to begin to extend through the wall of the ivc, suggesting at least a grade 2 interaction, but this cannot be confirmed.Another figure demonstrates approximately 22° of leftward filter tilt relative to the center line of the ivc, which resulted in the hook of the ivc filter abutting the wall of the ivc resulting in neointimal hyperplasia and ingrowth of the hook into the wall of the ivc.In addition, there is narrowing of the ivc in the region of the neck of the ivc filter suggesting an element of stenosis in this region.Per the report, patient was known to have a horseshoe kidney at time of placement and the filter was placed in the more typical location in the juxta renal/infrarenal ivc, but no placement imaging were submitted for review.Also, no imaging from the attempted retrieval's 3 months after placement was provided and there was no discussion as to why they were unsuccessful and of any advanced techniques potentially utilized during these attempts.4 years later, patient presented with left flank pain and gross hematuria due to the penetration of the filter into the renal parenchyma of the horseshoe kidney.Per the case report, advanced maneuvers including "bidirectional venous access, loop snare technique, and balloon angioplasty" failed to level the hook from the wall of the ivc and failed to retrieve the ivc filter.There is no discussion as to why endobronchial forceps were not used.In addition, the endovascular retrieval was abandoned after a reported limb fracture, although, the reported fractured limb was never identified on ct scan of the chest, nor could be found at the time of reported fracture.On all of the images submitted for review, the filter does appear to demonstrate a significant tilt which resulted in ingrowth of the filter hook into the wall of the ivc, and also either contributed to the accentuated penetration through the ivc wall and into the renal parenchyma or vice versa: nor can it be determined, if this occurred between the initial placement and the time of initial retrieval attempt or may have been a product of the initial failed retrieval attempts.In addition, as alluded to in the case report, patient's variant anatomy with a horseshoe kidney, resulted in extrinsic compression of the infrarenal ivc due to the location of the renal parenchyma anterior to the ivc, pressing on the ivc.This extrinsic compression likely directly contributed to the development of penetration of the filter legs over the extended dwell time.The complaint report states the horseshoe kidney anatomy was known at time of ivc filter placement.Given this known variant anatomy, a suprarenal ivc filter placement would have decreased the risk of renal parenchymal penetration.In addition, the reported fractured limb was never found, and there was no comment regarding the extracted ivc filter, if it was indeed missing a limb.Filter tilt is a known risk in relation to filter implant reported in the published scientific literature and may occur during placement or during implanting period.Vena cava wall perforation is a known potential complication of vena cava filters.Both symptomatic and asymptomatic events have been reported.Among other causes, vena cava wall perforation may inadvertently be initiated by improper deployment, excessive force or manipulations near an implanted filter (e.G., a surgical procedure in the vicinity of a filter) and (or) procedures that involve other devices being passed through an in situ filter.Filter fracture is a known potential complication of vena cava filters.Both symptomatic and asymptomatic events have been reported.Fracture of a filter leg can be due to repetitive motion on a filter leg in an unusual stressed position.Among other causes, filter fracture may be associated with a filter leg perforating the ivc, a filter leg being caught in a side branch (e.G.Renal vein), excessive force or manipulations near an implanted filter (e.G.A surgical procedure in the vicinity of a filter) and / or procedures that involve other devices being passed through an in situ filter.It has been reported that retrieval of a fractured filter or filter fragments using endovascular techniques is possible.Fracture of the wire is a known risk in relation to an implanted filter and reported in the published scientific literature.It is known from the published scientific literature that filter fragment embolized into the heart or lung may be safely retrieved.Filter retrieval is occasionally difficult.This is well-known from published scientific literature where filter retrievals are referred to as simple vs.Complex.Several case reports published in scientific literature describe complex cases with successful endovascular filter retrievals using additional, advanced techniques.There is no evidence to suggest that this celect filter was not manufactured according to specifications and nothing indicates that it did not perform as intended, e.G.Intended for the prevention of recurrent pulmonary embolism (pe) via placement in the vena cava.Cook medical will continue to monitor for similar events.This report is required by the fda under 21 cfr part 803.This report is based on unconfirmed information submitted by others.Neither the submission of this report nor any statement made in it is intended to be an admission that any cook device is defective or malfunctioned; that a death or serious injury occurred; or that any cook device caused or contributed to; or is likely to cause or contribute to a death or serious injury if a malfunction occurred.
|
