COOK Medical Zenith Flex Series, Инструкция по эксплуатации

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• 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.
Table 12.1 lists the minimum imaging follow-up for patients with the Zenith
Flex AAA Endovascular Graft. Patients requiring enhanced follow-up should
have interim evaluations.
Table 12.1 Recommended Imaging Schedule for Endograft Patients
Angiogram
CT
(Contrast and
non-contrast)
Abdominal
Radiographs
Pre-procedure X 1 X 1
Procedural X
Pre-discharge (within 7 days) X 2,3,4 X
1 month X 2,3,4 X
3 month X 2,4,5
6 month X 2,4 X
12 month (annually thereafter) X 2,4 X
1
Imaging should be performed within 6 months before the procedure.
2 Duplex ultrasound may be used for those patients experiencing renal failure or who are
otherwise unable to undergo contrast enhanced CT scan. With ultrasound, non-contrast
CT is still recommended.
3
Either pre-discharge or 1 month CT recommended.
4 If Type I or III endoleak, prompt intervention and additional follow-up post-intervention
recommended, see Section 12.6, Additional Surveillance and Treatment .
5
Recommended if endoleak reported at pre-discharge or 1 month.
12.2 Contrast and Non-Contrast CT Recommendations
• Film sets should include all sequential images at lowest possible slice
thickness (≤3 mm). DO NOT perform large slice thickness (>3 mm) and/or
omit consecutive CT images/film sets, as it prevents precise anatomical and
device comparisons over time.
• All images should include a scale for each film/image. Images should be
arranged no smaller than 20:1 images on 14 inch x 17 inch sheets if film is
used.
• Both non-contrast and contrast runs are required, with matching or
corresponding table positions.
• Pre-contrast and contrast run slice thickness and interval must match.
• DO NOT change patient orientation or re-landmark patient between non-
contrast and contrast runs.
Non-contrast and contrast enhanced baseline and follow-up imaging are
important for optimal patient surveillance. It is important to follow acceptable
imaging protocols during the CT exam. Table 12.2 lists examples of
acceptable imaging protocols.
Table 12.2 Acceptable Imaging Protocols
Non-Contrast Contrast
IV contrast No Yes
Acceptable machines
Spiral capable of
>40 seconds
Spiral capable of >40 seconds
Injection volume n/a 150 cc
Injection rate n/a >2.5 cc/sec
Injection mode n/a Power
Bolus timing n/a
Test bolus: SmartPrep, C.A.R.E.
or equivalent
Coverage - start Diaphragm 1 cm superior to celiac axis
Coverage - finish Proximal femur Profunda femoris origin
Collimation <3 mm <3 mm
Reconstruction
2.5 mm throughout –
soft algorithm
2.5 mm throughout – soft
algorithm
Axial DFOV 32 cm 32 cm
Post-injection runs None None
12.3 Abdominal Radiographs
The following views are required:
• Four films: supine-frontal (AP), cross-table lateral, 30 degree LPO and 30
degree RPO views centered on umbilicus.
• Record the table-to-film distance and use the same distance at each
subsequent examination.
Ensure entire device is captured on each single image format lengthwise.
If there is any concern about the device integrity (e.g., kinking,
stent breaks, barb separation, relative component migration), it is
recommended to use magnified views. The attending physician should
evaluate films for device integrity (entire device length including
components) using 2-4X magnification visual aid.
12.4 Ultrasound
Ultrasound imaging may be performed in place of contrast CT when patient
factors preclude the use of image contrast media. Ultrasound may be
paired with non-contrast CT. A complete aortic duplex is to be videotaped
for maximum aneurysm diameter, endoleaks, stent patency and stenosis.
Included on the videotape should be the following information as outlined
below:
• Transverse and longitudinal imaging should be obtained from the level of
the proximal aorta demonstrating mesenteric and renal arteries to the iliac
bifurcations to determine if endoleaks are present utilizing color flow and
color power angiography (if accessible).
• Spectral analysis confirmation should be performed for any suspected
endoleaks.
• Transverse and longitudinal imaging of the maximum aneurysm should be
obtained.
12.5 MRI Safety and Compatibility
Non-clinical testing has demonstrated that the Zenith AAA Endovascular Graft
is MR Conditional. It can be scanned safely under the following conditions:
1.5 Tesla Systems:
• Static magnetic field of 1.5 Tesla
• Spatial gradient field of 450 Gauss/cm
• Maximum whole-body-averaged specific absorption rate (SAR) of
2.0 W/kg for 15 minutes of scanning
In non-clinical testing, the Zenith AAA Endovascular Graft produced a
temperature rise of less than or equal to 1.4 °C at a maximum whole-body-
averaged specific absorption rate (SAR) of 2.8 W/kg, as assessed by calorimetry
for 15 minutes of MR scanning in a 1.5 Tesla Magnetom, Siemens Medical
Magnetom, Numaris/4 Software, Version Syngo MR 2002B DHHS MR Scanner.
The maximum whole-body-averaged specific absorption rate (SAR) was
2.8 W/kg, which corresponds to a calorimetry measured value of 1.5 W/kg.
3.0 Tesla Systems:
• Static magnetic field of 3.0 Tesla
• Spatial gradient field of 720 Gauss/cm
• Maximum whole-body-averaged specific absorption rate (SAR) of
2.0 W/kg for 15 minutes of scanning
In non-clinical testing, the Zenith AAA Endovascular Graft produced a
temperature rise of less than or equal to 1.9 °C at a maximum whole-
body-averaged specific absorption rate (SAR) of 3.0 W/kg, as assessed by
calorimetry for 15 minutes of MR scanning in a 3.0 Tesla Excite, GE Electric
Healthcare, G3.0-052B Software, MR Scanner. The maximum whole-body-
averaged specific absorption rate (SAR) was 3.0 W/kg, which corresponds to a
calorimetry measured value of 2.8 W/kg.
The image artifact extends throughout the anatomical region containing the
device, obscuring the view of immediately adjacent anatomical structures
within approximately 20 cm of the device, as well as the entire device and its
lumen, when scanned in non-clinical testing using the sequence: Fast spin
echo, in a 3.0 Tesla, Excite, GE Electric Healthcare, with G3.0-052B Software, MR
system with body radiofrequency coil.
For all scanners, the image artifact dissipates as the distance from the device
to the area of interest increases. MR scans of the head and neck and lower
extremities may be obtained without image artifact. Image artifact may be
present in scans of the abdominal region and upper extremities, depending
on distance from the device to the area of interest.
Clinical information is available for seventeen patients who received MRI scans
after stent-graft implantation. There have been no reported adverse events
or device problems in any of these patients as a result of having received an
MRI. Additionally, there have been well over 50,000 Zenith AAA Endovascular
Grafts implanted worldwide, in which there have been no reported adverse
events or device problems as a result of MRI.
Cook recommends that the patient register the MR conditions disclosed in
this IFU with the MedicAlert Foundation. The MedicAlert Foundation can be
contacted in the following manners:
Mail: MedicAlert Foundation International
2323 Colorado Avenue
Turlock, CA 95382 USA
Phone: 888-633-4298 (toll free)
+1 209-668-3333 from outside the US
Fax: +1 209-669-2450
Web: www.medicalert.org
12.6 Additional Surveillance and Treatment
Additional surveillance and possible treatment is recommended for:
• Aneurysms with Type I endoleak
• Aneurysms with Type III endoleak
• Aneurysm enlargement, ≥5 mm of maximum diameter (regardless of
endoleak status)
• Migration
• Inadequate seal length
Consideration for reintervention or conversion to open repair should include
the attending physician's assessment of an individual patient's co-morbidities,
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.
13 PATIENT TRACKING INFORMATION
In addition to these Instructions for Use, the Zenith Flex AAA Endovascular
Graft with the H&L-B One-Shot Introduction System is packaged with a Device
Tracking Form which the hospital staff is required to complete and forward
to COOK for the purposes of tracking all patients who receive the Zenith Flex
AAA Endovascular Graft (as required by U. S. Federal Regulation).
14 TROUBLESHOOTING
NOTE: Technical assistance from a Cook product specialist may be obtained
by contacting your local Cook representative.
14.1 Trigger-Wire Release Troubleshooting
CAUTION: The following steps should be performed only if unable to
remove the proximal trigger-wire as described in section 11.1.7.
14.1.1 Main Body Proximal (Top) Deployment
1. If the black (top cap) trigger-wire release mechanism cannot be removed
from the handle, cut the wire adjacent to the release mechanism (Fig. 37)
and remove the release mechanism from the handle.
2. Stabilize the gray positioner while withdrawing the sheath to fully deploy
the ipsilateral limb.
3. Remove the safety lock from the white trigger-wire release mechanism.
4. Withdraw and remove the trigger-wire by sliding the white trigger-wire
release mechanism off the handle, and then remove via its slot over the
device inner cannula.
5. Using locking forceps, clamp and secure the cut end of the top cap
trigger-wire. (Fig. 38)
6. Loosen the pin vise and, while maintaining inner cannula and trigger-wire
position, advance the gray positioner and sheath into the graft until the
tip of the gray positioner is approximately 2 cm from the gold markers.
(Fig. 39) The advanced gray positioner provides added support to the
inner cannula.
NOTE: Maintain gentle tension on the trigger-wire to remove any slack in the
wire as the gray positioner and sheath are being advanced.
NOTE: Ensure that the tip of the gray positioner is not advanced into the top
cap.
7. Lock the pin vise. Confirm that the trigger-wire is secured to the forceps.
8. Stabilize the gray positioner and slowly advance the sheath until the
sheath tip is 2 mm from the gold markers. (Fig. 40)
NOTE: Take care not to advance the graft itself during sheath advancement.
9. Stabilize the sheath and retract the gray positioner with inner cannula to
draw the top cap over the suprarenal stent. (Fig. 41)
10. Verify position of the gold markers inferior to the renal arteries.
11. Remove the trigger-wire.
12. Withdraw the sheath until the tapered tip of the gray positioner is
exposed.
13. Advance a molding balloon through the contralateral limb of the main
body and position it just superior to the graft bifurcation.
14. Inflate the balloon to the full diameter of the graft. (Fig. 42)
15. Loosen the pin vise.
16. Stabilize the gray positioner and balloon catheter, and advance the inner
cannula to deploy the top cap.
17. Tighten the pin vise.
18. Deflate the balloon and advance the contralateral wire guide into the
thoracic aorta.
NOTE: Due to early ipsilateral leg deployment and trigger-wire release, it is
suggested to leave the molding balloon in or just above the contralateral
limb for graft stabilization during placement of the ipsilateral limb.