Physician-Modified Endografts for Complex Aortic Aneurysms and Thoracoabdominal Aneurysm Repair in High-Risk Patients
Trial Snapshot
- Phase
- Not Applicable
- Status
- Active, not recruiting
- Sponsor
- Enrollment
- 15
- Locations
- 1
- Primary Endpoint
- Mortality
Study Overview
Brief Summary
This single-arm FDA-monitored protocol intends to broaden endovascular device applicability using physician-modifications in patients who A) Have anatomical conditions not amenable to endovascular repair using currently marketed grafts in the United States. B) Are at high risk for open surgical repair. C) Are high-risk subjects with previously placed endovascular devices and have developed failure of their previous devices. The use of physician-modified endografts aims to shift the seal zone proximally above the celiac artery in order to treat their complex or thoracoabdominal aneurysms in a minimally invasive fashion. These patients are considered too high risk to survive open surgical repair and do not meet anatomic criteria for the Gore Thoracoabdominal Multi Branch Endoprosthesis, which is currently the only FDA approved device in the US to treat these aneurysms.
The primary objective is to evaluate safety and effective of physician modified endografts in the treatment of thorax-abdominal aneurysms and complex aortic aneurysms. For primary safety endpoints, mortality and major adverse events (MAE) will be analyzed at 30 days or in hospitalization (if this exceeds 30 days). Primary endpoints include the following: 1. Mortality related to primary aortic disease 2. Aneurysm rupture 3. All cause mortality
For primary effectiveness endpoints, treatment success will be analyzed as the proportion of patients to achieve treatment success at 12 months. Treatment success is defined by a composite endpoint, which includes all of the following criteria: Technical success (defined as successful delivery and deployment of the physician modified endograft with perseveration of those branch vessels intended to be preserved, freedom from type I or type III endoleak, freedom from stent graft migration, freedom from aneurysm enlargement >5mm, freedom from aneurysm rupture or conversion to open repair.
Secondary objectives of the study include assessment of individual safety and effectiveness endpoints as follows: technical success, procedure success, mortality, major adverse events - specifically renal, cardia, pulmonary, gastrointestinal, and neurologic. Each endpoint will be analyzed separately. Secondary endpoints will be individually analyzed at 4-8 weeks, 6 months, and annually at 1,2,3,4, and 5 years.
Secondary endpoints to be analyzed are the following: 1. Evidence of Aortic Disease Progression: Monitoring for aneurysm growth > 5 mm from baseline measurements. 2. Device Failure: Evaluation of device performance, including migration > 10 mm, device degradation, and loss of device integrity. 3. Endoleaks: Monitoring for the occurrence and classification of endoleaks as outlined in the clinical outcome definitions. 4. Secondary Interventions: Description and analysis of secondary interventions aimed at treating branch vessel stenosis, occlusion, or embolization. 5. Significant Lifestyle-Limiting or Disabling Complications: Assessment and reporting of complications resulting in significant impairment of daily life, such as stroke-induced paralysis (paraplegia). 6. Cardiac Dysfunction: Monitoring and analysis of cardiac events, including myocardial infarction, congestive heart failure, and cardiac ischemia requiring intervention. 7. Renal Events: Evaluation of renal complications, including the need for dialysis, deterioration of renal function, and renal failure. 8. Mesenteric Events: Description and classification of mesenteric complications, such as ischemia and the need for surgical resection. 9. Respiratory Events: Monitoring for respiratory complications, including respiratory failure and prolonged intubation
Secondary endpoints will be individually analyzed at 4-8 weeks, 6 months, and annually at 1,2,3,4, and 5 years
Detailed Description
The devices employed in this study are Cook Medical products designed and approved for the treatment of thoracic and abdominal aortic diseases. These devices are constructed with full- thickness woven polyester fabric sewn to self-expanding stainless steel or nitinol Cook-Z stents, utilizing braided polyester and monofilament polypropylene sutures. Available in straight or tapered configurations, both variants are fully stented to ensure stability and the required expansile force for lumen opening during deployment. The devices encompass the Zenith TX2 dissection endovascular grafts and the Zenith Alpha thoracic endovascular grafts. These modular components are used in conjunction with other endovascular grafts to establish suitable proximal and distal sealing zones.
The selection of graft sizes is based on findings from preoperative radiologic studies, including computerized tomography (CT) and, if necessary, conventional angiography. Sizing of Zenith endovascular devices adheres to their respective instructions for use. The chosen outside diameter of the Zenith endovascular graft should be 15-25% larger than the proximal
implantation site. Similarly, the attachment site for the distal implantation is oversized by approximately 15-25%. This optimal graft-to-vessel diameter ratio aims to enhance the likelihood of achieving a secure seal with the vessel wall, mitigating the risk of graft migration, endoleaks, and thrombosis.
The majority of cases involve thoracoabdominal aneurysms, with some encompassing paravisceral and pararenal aneurysms. For the former, fenestrations will be used to preserve flow to visceral vessels, while the latter will involve branches to maintain flow. The goal is to achieve at least 20mm of seal within the normal proximal aorta and 15mm of seal distally in the iliac arteries.
Branches will primarily be used where the aortic diameter at the level of the visceral or renal branches is >28mm in size. When branches are to be used, 6-8mm fenestrations will be burned 20mm above the target vessel based on centerline measurements described above. A branch will be created by cutting a self-expanding Gore Viabahn stent to 15mm in length and suturing this onto the fenestration in a running fashion using a Gore-Tex suture. The size of the fenestration and the size of the Viabahn stent will be patient on target vessel size and will be created accordingly.
Study Design
- Study Type
- Interventional
- Allocation
- Na
- Intervention Model
- Single Group
- Primary Purpose
- Treatment
- Masking
- None
Eligibility Criteria
- Ages
- 18 Years to — (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •Patient is > 18 years of age.
- •Patients who are male or non-pregnant female (females of childbearing potential must have a negative pregnancy test prior to enrollment into the study)
- •Patient is able and willing to sign an Institutional Review Board (IRB) approved Informed Consent Form
- •The subject has at least one of the following:
- •. An aortic or aortoiliac aneurysm with a maximum diameter of ≥ 5.5cm for males, ≥ 5.0cm for females
- •Aortic Aneurysm with a history of growth ≥ 0.5 cm in 6 mos.
- •Symptomatic aneurysm
- •Morphology such as saccular aneurysms
- •Aneurysms meeting any of the above criteria a-e above or below the previous endovascular and/or open aortic repairs. Previously placed aortic stent graft or open aortic grafts may serve as seal zones.
- •Cannot be treated with a currently available non-modified approved device.
- •Patient has patent iliac or femoral arteries that will allow endovascular access with the physician modified graft or is suitable for an iliac conduit.
- •Patient has a suitable non-aneurysmal proximal aortic neck length (seal zone) of ≥ 20mm.
- •Patient has a suitable non-aneurysmal distal iliac artery length (seal zone) of ≥15mm.
- •The resultant repair should preserve patency in at least one hypogastric artery.
- •Patient has suitable non-aneurysmal distal common iliac diameters between 7 and 20mm.
- •Chronic Dissection with aneurysmal degeneration that meets size criteria as described above for repair
- •Type 1A endoleak requiring extension above the previous repair into the pararenal or paravisceral portion of the aorta to achieve 2 cm of seal.
Exclusion Criteria
- •patient has a mycotic aneurysm
- •patient has a systemic or local infection that may increase the risk of graft infection.
- •Body habitus that would inhibit x-ray visualization of the aorta or exceeds the safe capacity of the equipment.
- •Subject has had a major surgical or interventional procedure unrelated to the treatment of the aneurysm planned < 30 days of the endovascular repair.
- •Patient is currently participating in another investigational device or drug clinical trial.
- •Eligible for treatment with FDA-approved marketed device
- •Can enroll in a manufacturer-sponsored clinical study at our institution or is willing and eligible to participate in a study with a manufacturermade device at another institution.
- •Unwilling to comply with the follow-up schedule.
- •Inability or refusal to give informed consent by subject or legal representative. - The subject is pregnant or breastfeeding.
- •Known sensitivities or allergies to the materials of construction of the devices, including stainless steel, polyester, polypropylene, nickel, titanium, or gold. - Known hypersensitivity or contraindication to anticoagulation or contrast media that is not amenable to pretreatment
- •Uncorrectable coagulopathy
- •Unstable angina (defined as angina with a progressive increase in symptoms, new onset at rest or nocturnal angina)
- •Systemic or local infection that may increase the risk of endovascular graft infection.
- •History of connective tissue disorders (e.g., Marfan Syndrome, Ehlers's Danlos Syndrome) without landing zone created from graft via previous open repair. - Patient has active malignancy with life expectancy of less than 2 years.
- •Patient has a limited life expectancy of less than 2 years.
- •Patient has other medical, social, or psychological conditions that, in the opinion of the investigator, preclude them from receiving the pretreatment, required treatment, and post-treatment procedures and evaluations.
- •Anatomical exclusion criteria such as significant occlusive disease, tortuosity or calcification that would prevent endovascular access.
- •proximal seal site with a circumferential thrombus/atheroma
- •inability to maintain at least one hypogastric artery.
- •shaggy aorta
- •patient is not amenable to a temporary or permanent open surgical or endovascular conduit.
- •Thrombus or excessive calcification within the neck of the aneurysm
Arms & Interventions
Thoracoabdominal and aortic aneurysm arm
The Zenith Endovascular graft is a tubular graft made of polyester fabric sewn to stainless steel stents that keep the graft open. The physician will be creating fenestrations or branches' locations based on the the patient's anatomy. The graft will be inserted through arteries in the leg (called endovascular repair). This procedure uses catheters that go inside the blood vessel to place a stent graft above and below the aneurysm.
The graft includes 1 to 5 small holes (fenestrations) or cuffs (side branches). The arteries to the liver, intestine, and kidneys will be have a stent (small tubular stainless steel structures) to help keep the arteries open and aligned with the fenestrations or branches.
Intervention: Physician Modified Endograft (Device)
Outcomes
Primary Outcomes
Mortality
Time Frame: 5 years
Primary endpoints include the following: Mortality related to primary aortic disease or all cause mortality during the 5 year follow up of the study
Aneurysm rupture
Time Frame: 5 years
Any imaging or clinical evidence of rupture of the aortic aneurysm being treated
Secondary Outcomes
- Significant Lifestyle-limiting or disabling complications(5 years)
- Cardiac dysfunction(5 years)
- Renal events(5 years)
- Mesenteric Events(5 years)
- Evidence of Aortic Disease Progression(5 years)
- Device Failure(5 years)
- Endoleaks(5 years)
- Secondary Interventions(5 years)
- Respiratory events(5 years)
Investigators
Steven Maximus
Associate Professor of Surgery
Baylor College of Medicine