Device Length Sizing Guidelines; Directions For Use; Anatomical Requirements; Proximal And Distal Component Overlap - COOK Medical Zenith Alpha Mode D'emploi

9.6 Device Length Sizing Guidelines

• Graft length should be selected to cover the aneurysm or ulcer measured
along the greater curve of the aneurysm, plus a minimum of 20 mm of seal
zone on the proximal and distal ends.
• To treat more focal aortic lesions, such as ulcers/saccular aneurysms, a
proximal component can be used alone.
• In aneurysms the graft may settle into the greater curve of the aneurysm
over time. Accordingly, extra graft length needs to be planned:
• A two-component repair (proximal and distal component) is
recommended, as it provides the ability to adapt to the length change
over time. A two-component repair (proximal and distal component) also
provides active fixation at both the proximal and distal seal sites.
• The minimum required amount of overlap between devices is three stents.
Less than a three-stent overlap may result in endoleak (with or without
component separation). However, no part of the distal component should
overlap the proximal sealing stent of the proximal component, and no
part of the proximal component should overlap the distal sealing stent of
the distal component, as doing so may cause malapposition to the vessel
wall. Device lengths should be selected accordingly.
• If an acceptable two-component (proximal and distal component)
treatment plan cannot be achieved (e.g., excessive aortic coverage, even
with maximal overlap of shortest components), the proximal component
must be selected with enough length to achieve and maintain the
minimum 20 mm sealing zones at both ends even when positioned in the
greater curve of the aneurysm. Clinical experience shows that failure to do
so could result in migration, endoleak, and aneurysm growth.

10 DIRECTIONS FOR USE

Anatomical Requirements

• Iliofemoral access vessel size and anatomy (minimal thrombus, calcium and/
or tortuosity) should be compatible with vascular access techniques and
accessories. Arterial conduit technique may be required.
• Proximal and distal aortic neck lengths should be a minimum of 20 mm.
• Aortic neck diameters measured outer-wall-to-outer-wall should be between
20-42 mm.
• A proximal neck diameter that is 4 mm or more larger than the distal neck
diameter requires the use of a proximal tapered component.
• No localized angulation should be larger than 45 degrees.
• Measurements to be taken during the pre-treatment assessment are shown
in Fig. 3.

Proximal and Distal Component Overlap

A minimum overlap of three stents is recommended; however, the proximal
sealing stent of the proximal component or distal sealing stent of the distal
component should not be overlapped.
Prior to use of the Zenith Alpha Thoracic Endovascular Graft, review the
Suggested Instructions for Use booklet. The following instructions are
intended to help guide the physician and do not take the place of physician
judgment.

General Use Information

Standard techniques for placement of arterial access sheaths, guiding catheters,
angiographic catheters, and wire guides should be employed during use
of the Zenith Alpha Thoracic Endovascular Graft. The Zenith Alpha Thoracic
Endovascular Graft is compatible with .035 inch diameter wire guides. Brachio-
femoral wire guide technique may be required if the patient has a difficult
anatomy.
Endovascular stenting is a surgical procedure, and blood loss from various
causes may occur, infrequently requiring intervention (including transfusion)
to prevent adverse outcomes. It is important to monitor blood loss from the
hemostatic valve throughout the procedure, but is specifically relevant during
and after manipulation of the gray positioner. After the gray positioner has
been removed, if blood loss is excessive, consider placing an uninflated molding
balloon or an introduction system dilator within the valve to restrict flow.

Pre-Implant Determinants

Verify from pre-implant planning that the correct device has been selected.
Determinants include:
• Femoral artery selection for introduction of the introduction system(s)
• Angulation of aorta, aneurysm, and iliac arteries
• Quality of the proximal and distal fixation sites
• Diameters of proximal and distal fixation sites and distal iliac arteries
• Length of proximal and distal fixation sites

Patient Preparation

1. Refer to institutional protocols relating to anesthesia, anticoagulation, and
monitoring of vital signs.
2. Position the patient on the imaging table to allow fluoroscopic visualization
from the aortic arch to the femoral bifurcations.
3. Expose the femoral artery using standard surgical technique.
4. Establish adequate proximal and distal vascular control of the femoral
artery.

10.1 The Zenith Alpha Thoracic Endovascular Graft

10.1.1 Proximal and Distal Components Preparation/Flush

1. Remove the yellow-hubbed inner stylet from the dilator tip. Verify that the
Captor Sleeve is within the Captor Hemostatic Valve; do not remove the
Captor Sleeve. (Fig. 4)
2. Elevate the distal tip of the system and flush through the hemostatic valve
until fluid exits the tip of the introducer sheath. (Fig. 5) Continue to inject
a full 60 mL of flushing solution through the device. Discontinue injection
and close the stopcock on the connecting tube.
NOTE: Graft flushing solution of heparinized saline is often used.
3. Attach a syringe with heparinized saline to the hub on the blue rotation
handle. (Fig. 6) Flush until fluid exits the distal sideports and dilator tip.
4. Soak sterile gauze pads in saline solution and use them to wipe the Flexor
Introducer Sheath to activate the hydrophilic coating. Hydrate both sheath
and dilator tip liberally.

10.1.2 Placement of Proximal Component

1. Puncture the selected artery using standard technique with an 18 gage
access needle. Upon vessel entry, insert:
• Wire guide – (standard .035 inch, 260/300 cm, 15 mm J tip or Bentson)
• Appropriate size sheath (e.g., 5 French)
• Pigtail flush catheter (often radiopaque-banded sizing catheters; e.g., Cook
Centimeter Sizing CSC-20 catheter)
2. Perform angiography at the appropriate level. If using radiopaque markers,
adjust position of the catheter as necessary and repeat angiography.
3. Ensure the graft system has been flushed and primed with heparinized
saline (appropriate flush solution), and that all air has been removed.
4. Give systemic heparin. Flush all catheters and wet all wire guides with
heparinized saline. Reflush catheters and rewet wire guides after each
exchange.
5. Replace the standard wire guide with a stiff .035 inch, 260/300 cm, LESDC
wire guide and advance through the catheter and up to the aortic arch.
NOTE: If the anatomy is difficult, consider using a brachio-femoral approach
instead.
6. Remove the pigtail flush catheter and sheath.
NOTE: At this stage, the second femoral artery can be accessed for
angiographic catheter placement. Alternatively, consider using a brachial
approach.
7. Introduce the freshly hydrated introduction system over the wire guide and
advance it until the desired graft position is reached.
CAUTION: To avoid inadvertent displacement of the graft during
withdrawal of the sheath, it may be appropriate to momentarily
decrease the patient's mean arterial pressure to approximately
80 mm Hg (at the discretion of the physician).
CAUTION: To avoid twisting the endovascular graft, never rotate
the introduction system when you introduce it. Allow the device to
conform naturally to the curves and tortuosity of the vessels.
NOTE: The dilator tip will soften at body temperature.
8. Verify wire guide position in the aortic arch. Ensure correct graft position.
CAUTION: Care should be taken not to advance the sheath while the
stent graft is still within it. Advancing the sheath at this stage may
cause the barbs to perforate the introducer sheath.
9. Ensure that the Captor Hemostatic Valve on the Flexor Introducer Sheath is
turned to the open position. (Fig. 7)
10. Stabilize the gray positioner (introduction system shaft) and withdraw the
sheath until the graft is fully expanded and the valve assembly with the
Captor Sleeve docks with the black gripper. (Fig. 8)
CAUTION: As the sheath is withdrawn, anatomy and graft position may
change. Prior to complete unsheathing of the graft, check distal gold
markers to make sure visceral arteries will not be covered. Constantly
monitor graft position and perform angiography to check position as
necessary.
CAUTION: During sheath withdrawal, the proximal barbs are exposed
and are in contact with the vessel wall. At this stage it may be possible
to advance the device, but retraction may cause aortic wall damage.
NOTE: If extreme difficulty is encountered when attempting to withdraw
the sheath, place the device in a less tortuous position that enables the
sheath to be retracted. Very carefully withdraw the sheath until it just
begins to retract, and stop. Move back to original position and continue
deployment.
11. Verify graft position and, if necessary, adjust it forward. Recheck graft
position with angiography.
NOTE: If an angiographic catheter is placed parallel to the stent graft, use
the catheter to perform position angiography.
12. While holding the black gripper, turn the black safety-lock knob in the
direction of the arrows until a slight click is felt, indicating that the blue
rotation handle is engaged. (Fig. 9) Make sure the black safety-lock knob is
in the unlocked position.
13. Under fluoroscopy, turn the blue rotation handle in the direction of the
arrow until a stop is felt. (Fig. 10) This indicates that the uncovered stent
and proximal end of the graft have opened and that the distal attachment
to the introducer has been released.
NOTE: If the blue rotation handle stops before completing the rotation (so
that the proximal end of the graft is not released from the introduction
system), verify the position of the black safety-lock knob and, if necessary,
turn it counterclockwise to the unlocked position.
NOTE: If the black safety-lock knob is removed from the system after it has
been turned counterclockwise to the unlocked position, the blue rotation
handle will remain engaged. Continue with the procedure.
NOTE: If it is still difficult to rotate the blue rotation handle, refer to
Section 12, RELEASE TROUBLESHOOTING for instructions on how to
disassemble the blue rotation handle.
14. Remove the introduction system, leaving the wire guide in the graft.
CAUTION: To avoid entangling any catheters left in situ, rotate the
introduction system during withdrawal.
NOTE: Inaccuracies in device size selection or placement, changes or
anomalies in patient anatomy, or procedural complications may require
placement of additional endovascular grafts and extensions to achieve the
minimum length of proximal and distal seal and length of overlap between
components.

10.1.3 Placement of Distal Component

1. If an angiographic catheter is placed in the femoral artery, it should
be repositioned to demonstrate the aortic anatomy where the distal
component is to be deployed.
2. Introduce the freshly hydrated introduction system over the wire guide
until the desired graft position is reached, with at minimum a three-stent
overlap (75 mm) with the proximal component. No part of the distal
component should overlap the proximal sealing stent of the proximal
component, and no part of the proximal component should overlap
the distal sealing stent of the distal component, as doing so may cause
malapposition to the vessel wall.
3. Check the graft position by angiography and adjust if necessary.
4. Ensure that the Captor Hemostatic Valve on the Flexor Introducer Sheath is
turned to the open position. (Fig. 7)
5. Stabilize the gray positioner (introduction system shaft) and begin
withdrawing the sheath.
CAUTION: As the sheath is withdrawn, anatomy and graft position may
change. Constantly monitor graft position and perform angiography to
check position as necessary.
NOTE: If extreme difficulty is encountered when attempting to withdraw
the sheath, place the device in a less tortuous position that enables the
sheath to be retracted. Very carefully withdraw the sheath until it just
begins to retract, and stop. Move back to original position and continue
deployment.
6. Withdraw the sheath until the Captor Valve with the Captor Sleeve docks
with the black telescoping gripper and the graft is fully expanded. (Fig. 11)
7. To release the distal attachment, hold the black telescoping gripper and
turn the black safety-lock knob in the direction of the arrows until a slight
click is felt, indicating that the blue rotation handle is engaged. Make sure
the black safety-lock knob is in the unlocked position. (Fig. 12) Turn the
blue rotation handle in the direction of the arrow next to label 1 until a stop
is felt. (Fig. 13)
NOTE: If the blue rotation handle stops before completing the rotation,
verify the position of the black safety-lock knob and, if necessary, turn it
counterclockwise to the unlocked position.
NOTE: If the black safety-lock knob is removed from the system after it has
been turned counterclockwise to the unlocked position, the blue rotation
handle will remain engaged. Continue with the procedure.
8. Turn the gray safety-lock knob indicated by label 2, on the black
telescoping gripper in the direction of the arrows until a slight click is felt,
indicating that the black telescoping gripper is engaged. (Fig. 14)
NOTE: Care should be taken to avoid landing the bare stent in regions of
localized angulation > 45 degrees. If the bare stent is landed in localized
angulations > 45 degrees, it may be difficult to release the bottom cap
(Clinical experience). Using a brachio-femoral wire guide technique can
increase support of the system and ease the release of the bottom cap.
9. To release the distal bare stent, stabilize the introduction system and slide
the sheath together with the black telescoping gripper (by holding the
Captor Valve) in a distal direction until it locks automatically into position
next to the blue rotation handle. (Fig. 15) The release window on the blue
rotation handle next to label 3 will turn green. (Fig. 16) If the window has
not turned green, slide the black telescoping gripper until it locks with the
blue rotation handle.
23