24
• The Zenith Flex AAA Endovascular Graft with the H&L-B One-Shot
Introduction System is not recommended in patients unable to undergo, or
who will not be compliant with, the necessary preoperative and
postoperative imaging and implantation studies as described in Section 12,
IMAGING GUIDELINES AND POSTOPERATIVE FOLLOW-UP.
• After endovascular graft placement, patients should be regularly monitored
for perigraft flow, aneurysm growth or changes in the structure or position
of the endovascular graft. At a minimum, annual imaging is required,
including: 1) abdominal radiographs to examine device integrity (separation
between components, stent fracture or barb separation) and 2) contrast and
non-contrast CT to examine aneurysm changes, perigraft flow, patency,
tortuosity and progressive disease. If renal complications or other factors
preclude the use of image contrast media, abdominal radiographs and
duplex ultrasound may provide similar information.
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
(Tables 10.5.1 and 10.5.2). 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
(Refer to Section 11, DIRECTIONS FOR USE)
• Appropriate procedural imaging is required to successfully position the
Zenith Flex AAA Endovascular Graft and assure accurate apposition to the
aortic wall.
• Do not bend or kink the delivery system. Doing so may cause damage to the
delivery system and the Zenith Flex AAA Endovascular Graft.
• To avoid any twist in the endovascular graft, during any rotation of the
delivery system, be careful to rotate all of the components of the system
together (from outer sheath to inner cannula).
• Do not continue advancing any portion of the delivery system if resistance
is felt during advancement of the wire guide or delivery system. Stop and
assess the cause of resistance; vessel, catheter or graft damage may occur.
Exercise particular care in areas of stenosis, intravascular thrombosis or in
calcified or tortuous vessels.
• Inadvertent partial deployment or migration of the endoprosthesis may
require surgical removal.
• Unless medically indicated, do not deploy the Zenith Flex AAA Endovascular
Graft in a location that will occlude arteries necessary to supply blood flow
to organs or extremities. Do not cover significant renal or mesenteric
arteries (exception is the inferior mesenteric artery) with the endoprosthesis.
Vessel occlusion may occur. During the clinical study, this device was not
studied in patients with two occluded internal iliac arteries.
• Do not attempt to re-sheath the graft after partial or complete deployment.
• Repositioning the stent graft distally after partial deployment of the covered
proximal stent may result in damage to the stent graft and/or vessel injury.
• 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.
• Systemic anticoagulation should be used during the implantation
procedure based on hospital and physician preferred protocol. If heparin is
contraindicated, an alternative anticoagulant should be considered.
• To activate the hydrophilic coating on the outside of the Flexor introducer
sheath, the surface must be wiped with sterile gauze pads soaked in saline
solution. Always keep the sheath hydrated for optimal performance.
• Minimize handling of the constrained endoprosthesis during preparation
and insertion to decrease the risk of endoprosthesis contamination and
infection.
• Maintain wire guide position during delivery system insertion.
• Fluoroscopy should be used during introduction and deployment to
confirm proper operation of the delivery system components, proper
placement of the graft, and desired procedural outcome.
• The use of the Zenith Flex AAA Endovascular Graft with the H&L-B One-Shot
Introduction System requires administration of intravascular contrast.
Patients with preexisting renal insufficiency may have an increased risk of
renal failure postoperatively. Care should be taken to limit the amount of
contrast media used during the procedure and to observe preventative
methods of treatment to decrease renal compromise (e.g., adequate
hydration).
• As the sheath and/or wire guide is withdrawn, anatomy and graft position
may change. Constantly monitor graft position and perform angiography to
check position as necessary.
• The Zenith Flex AAA Endovascular Graft incorporates a suprarenal stent with
fixation barbs. Exercise extreme caution when manipulating interventional
and angiographic devices in the region of the suprarenal stent.
• Use caution during manipulation of catheters, wires and sheaths within an
aneurysm. Significant disturbances may dislodge fragments of thrombus,
which can cause distal embolization, or rupture of the aneurysm.
• Avoid damaging the graft or disturbing graft positioning after placement in
the event reinstrumentation (secondary intervention) of the graft is
necessary.
• Before deployment of the suprarenal stent, verify that the position of the
access wire guide extends just distal to the aortic arch.
• Verify that the predetermined contralateral iliac leg is selected for insertion
on the contralateral side of the patient before implantation.
4.6 Molding Balloon Use
• Do not inflate the balloon in the vessel outside of the graft, as doing so may
cause damage to the vessel. Use the balloon in accordance with its labeling.
• Use care in inflating the balloon within the graft in the presence of
calcification, as excessive inflation may cause damage to the vessel.
• Confirm complete deflation of the balloon prior to repositioning.
• For added hemostasis, the Captor Hemostatic Valve can be loosened or
tightened to accommodate the insertion and subsequent withdrawal of a
molding balloon.
4.7 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:
Address:
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
5 ADVERSE EVENTS
5.1 Observed Adverse Events
A U.S. multicenter, prospective study of a previous version of the device
(Zenith AAA Endovascular Graft) conducted at 15 centers which included
352 endovascular patients (200 standard risk, 100 high risk and 52 roll-in) and
80 control patients provides the basis of the observed adverse event rates
in Table 5.1.1. Patients were enrolled in the standard risk arm if they were
physiologically capable of withstanding an open or endovascular repair and
had anatomy suitable for treatment with the Zenith AAA Endovascular Graft
with the H&L-B One-Shot Introduction System. Patients with suitable anatomy,
but at higher risk of morbidity or mortality with open repair were enrolled
into the high risk arm. Initial patients treated in the study were enrolled in the
roll-in arm. The control group included patients whose vascular anatomy may
not have been suitable for endovascular AAA repair.
Table 5.1.1 Death and Rupture from Clinical Study
Death and Rupture
Zenith Standard Risk
1
Surgical Standard Risk
P
value
Zenith High Risk
Zenith Roll-in
All death
(0-30 days)
2
0.5%
(1/199)
2.5%
(2/80)
.20
2.0%
(2/100)
1.9%
(1/52)
(31-365 days)
3
3.0%
(6/198)
1.3%
(1/78)
.68
7.1%
(7/98)
9.8%
(5/51)
AAA-related
0.0%
(0/198)
1.3%
(1/78)
.29
3.1%
(3/98)
0.0%
(0/51)
Non-AAA-related
3.0%
(6/198)
0.0%
(0/78)
.19
4.1%
(4/98)
9.8%
(5/51)
(0-365 days)
2,3,4
3.5%
(7/199)
3.8%
(3/80)
>.99
9.0%
(9/100)
11.5%
(6/52)
AAA-related
0.5%
(1/199)
3.8%
(3/80)
.07
5.0%
(5/100)
1.9%
(1/52)
Non-AAA-related
3.0%
(6/199)
0.0%
(0/80)
.19
4.0%
(4/100)
9.6%
(5/52)
Rupture
(0-30 days)
0.0%
(0/199)
n/a
n/a
0.0%
(0/100)
0.0%
(0/52)
(31-365 days)
0.0%
(0/198)
n/a
n/a
1.0%
(1/98)
0.0%
(0/51)
(0-365 days)
0.0%
(0/199)
n/a
n/a
1.0%
(1/100)
0.0%
(0/52)
1
Denominator of 199 because one standard risk patient did not receive a device.
2
All deaths (0-30 days) were considered AAA and procedure related.
3
Of the deaths (31-365 days), four were considered AAA related: 1 surgical (septic shock from ischemic colitis) and 3 high risk (pancreatitis with renal failure and sepsis, hemorrhage
from upper abdominal aneurysm [not treated AAA] and multiple system failure).
4
Of the deaths (0-365 days), ten were considered AAA related: 1 standard risk (cardiac failure), 3 surgical (massive hemorrhage, mesenteric ischemia and septic shock from ischemic
colitis), 5 high risk (respiratory failure, cardiac failure with pulmonary embolism, pancreatitis with renal failure and sepsis, hemorrhage from upper abdominal aneurysm [not treated
AAA] and multiple system failure) and 1 roll-in (suspected cardiac failure).
