Clinical Trial Details
— Status: Completed
Administrative data
NCT number |
NCT03024554 |
Other study ID # |
12-2013 |
Secondary ID |
|
Status |
Completed |
Phase |
N/A
|
First received |
|
Last updated |
|
Start date |
April 2014 |
Est. completion date |
June 2022 |
Study information
Verified date |
July 2019 |
Source |
Cardiatis |
Contact |
n/a |
Is FDA regulated |
No |
Health authority |
|
Study type |
Interventional
|
Clinical Trial Summary
To determine the safety and efficacy of the BMFM® kit in the use for the endovascular
treatment of aortic aneurysms involving iliac arteries. The BMFM® kit is an adaptation of the
aortic MFM® to the aortoiliac bifurcation morphology. It should be noted that the aortic MFM®
has CE mark approval for the aortic aneurysm treatment.
Description:
Endovascular approaches to TAAAs have evolved during the past decade. The initial experiences
with fenestrated and branched endografts have shown that total endovascular repair is
effective and may reduce morbidity rates in patients with arch, thoracoabdominal and
pararenal aneurysms.
The Cleveland Clinic group has recently reported on their updated clinical experience with
the first 633 patients treated by fenestrated and branched endografts. Operative mortality
was 1.8% for pararenal, 5.2% for types I to III, and 2.3% for type IV TAAAs .
However, 30-40% of TAAA patients remain unsuitable for EVAR due to unfavorable proximal neck
anatomy. There is also an increased incidence of type I proximal endoleak when established
f-EVAR guidelines are disregarded, often leading to endovascular re-intervention or surgical
conversion.
Currently, the use of the bifurcated stent-graft for the infrarenal aneurysm involving iliac
arteries treatment has received wide distribution. The application of endovascular technology
to treat infrarenal aneurysm is now commonplace because the implantation of an infrarenal
endoprosthesis is a relatively simple procedure requiring adequately long proximal seal zone,
diameter measurements and accurate longitudinal device placement. However, designing and
implanting a device, which will accommodate the visceral branches, is more complex.
The infrarenal with unfavorable or insufficient proximal neck as well as juxtarenal
aneurysms, which involve iliac arteries, could be treated by combination of the Fenestrated
Stent Graft with the Bifurcated Stent Graft.
The principal limitation of this technology is the customized nature of fenestrated
stent-graft design. From planning to delivery, the process may take in excess of 6 weeks,
which restricts the application of f-EVAR to stable elective patients. This procedure is
complex, costly and the implantation time is quite long. It must be conducted in expert
centers with sophisticated infrastructure (hybrid room). Preservation of visceral aortic
branches requires precise graft construction and deployment.
There are reports in the literature of emergent f-EVAR, but the success of these procedures
relies on on-site modification of commercially available endografts.
Until an "off-the-shelf'' device is designed to be compatible with the majority of patients,
''off-label'' surgeon-modified devices remain the only option in emergencies when open repair
is prohibited. The "off-the-shelf" devices are likely to allow treatment of more than 60% to
80% of patients with complex aneurysms but these standardized designs have not yet been
tested clinically in large number of patients with long follow-up In the absence of widely
available endografts designs, a number of centers have reported creative techniques to
incorporate the visceral arteries, such as "chimney", "sandwich" , "octopus" , "periscope"
and physician-modified endografts. However, these approaches are limited by off-label
indications, lack of quality control, violation of basic engineering concepts and
questionable durability.
One of the drawbacks linked to the use of parallel endografts (mainly for the "chimney
technique") remains the imperfect seal inherent to this technique. This side by side
configuration leads to gutter along the parallel endografts, which can result in type I
endoleaks between the main body of the graft and branched grafts; "Gutter endoleaks"
continuously pressurize the aneurysm. The gutters between the main aortic graft, the chimney
graft (GC), and the aortic wall should be as narrow as possible to avoid endoleaks, which can
be harmful and -almost always- require re-intervention.
Thoraco Abdominal Aneurysms involving iliac arteries remain a challenge for EVAR. Dilatation
of the common iliac artery (CIA) often leaves no distal landing zone for commercially
available stent grafts, which have a maximum diameter of 28 mm. Furthermore, aneurysms
extended to the internal iliac artery (IIA) make endovascular repair even more difficult.
A common method allowing endovascular treatment of these aneurysms is occlusion of the IIA,
thereby creating a distal landing zone in the external iliac artery (EIA). However,
sacrificing the pelvic blood flow while occluding the internal iliac artery often results in
buttock claudication and impotence, as well as other complications such as colonic
infarction, gut or spinal cord ischemia. The frequency of these complications varies between
13% and 55% and they can impair quality of life substantially.
Successful treatment of aortoiliac aneurysms involves branch vessel preservation and
long-term protection from rupture. While EVAR has totally eclipsed open surgery because of
its lower mortality and morbidities, the durability of EVAR can be questioned because of the
need for re-intervention and incidence of late aneurysm-related complications . Notably,
long-term failure can arise because of the loss of proper seal at the proximal or distal
landing zone of the stent-graft (type I endoleaks). Importantly, common iliac diameter can be
considered as a predictor of late sac enlargement, as well as implantation outside
Manufacturer's Instructions For Use (IFU). Furthermore, Benharash et al. managed to
demonstrate that iliac fixation is of high importance for the prevention of device migration,
regardless of proximal attachment type.
Iliac artery involvement incidence in abdominal aortic aneurysms (AAAs) is estimated at 20 to
30 %. Hence, nearly a third of all patients presenting with AAAs for repair might not fit
within the IFU for standard EVAR device based on iliac diameters. A common approach to ensure
appropriate landing zone for iliac components of endografts involves extension into the
external iliac artery, with or without concomitant hypogastric artery embolization and
coverage. While unilateral coiling has been demonstrated to have relatively low rates of
complication, occlusion of the hypogastric artery due to stent graft placement can lead to
major complications, as mentioned above. Given the significant morbidity associated with
these complications, industry has developed branch technology for hypogastric preservation.
The Multilayer Flow Modulator (MFM®) provides a less complex interventional approach for
aortic aneurysm treatment. This device is an uncovered, self-expanding wire mesh with high
radial force and flexibility. It is designed to modulate blood-flow dynamics by relieving
local peak wall shear stress (PWSS), achieving stabilization of aneurysm-sac or false lumen
pressure and preserving side-branch patency.
The clinical benefits of this technology have been assessed and shown in case reports and
clinical studies of thoracoabdominal aneurysm, type B dissection, pararenal aortic aneurysm
and peripheral artery aneurysm (celiac, hepatic, renal, iliac, subclavian) (48-79). Also the
prospective multicenter registry of peripheral and visceral aneurysms (69) and the
prospective multicenter STRATO Trial of TAAA (78), show good results at 12-month follow-up.
The MFM® eliminates flow vortex pressure and laminates the outside the device along the
aneurysm wall in the same direction of the blood stream. Laminated flow possess unique and
protective effects on endothelial cells as well as the ability to promote thrombus
progressive formation within the aneurysmal sac. The MFM® addresses not only those issues in
a very unique fashion, providing a uniform interface between the artery wall and the blood
flow, but its favorable compliance means the device will not be subjected to the same drag
forces a conventional stent graft will undergo..
Laminating the blood flow within the aneurysm, promoting thrombus formation within the
aneurysmal sac and re-establishing a favorable biochemical and biomechanical balance of
endothelial homeostasis, the MFM® addresses aneurysm related issues and outcomes in a novel
manner. With aneurysmal stabilization and thrombosis, the MFM® excludes the aneurysm from the
circulation rather physically and physiologically than mechanically, as other conventional
grafts do. Thanks to the intrinsic porosity of the device, branches are kept patent and well
perfused, thus abolishing the risk for collaterals occlusion and consequent ischemia.
STREAMLINER study is an international, multicentre, prospective, non-randomized study. It is
designed to evaluate the safety and efficacy of BMFM® kit use. Approximately 40 patients,
from up to 12 centres in Europe, Israel, Morocco, Bahrain and Turkey, will be enrolled and
screened per the protocol-required inclusion, exclusion criteria, in order to obtain 30
completed patients. The results will be compared with published results for other treatment
modalities in the literature. Patients will be included only after obtaining fully informed
consent, after conducting all pre-operative examinations required, with respect for all
inclusion and exclusion criteria. For early demonstration of efficacy and safety an interim
analysis will be performed after the 10 first enrolled patients will complete their 6 months
follow-up.