Safety and Efficacy of Multiple Overlapping Uncovered Stents for Pararenal Aortic Aneurysm Repair (SEMPER)
|Aortic Aneurysm Aortic Aneurysm, Abdominal Aortic Aneurysm, Thoracic Aortic Aneurysm, Thoracoabdominal||Procedure: Multiple overlapping uncovered stents Device: Uncovered stents|
|Study Design:||Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
|Official Title:||Evaluation of the Safety and Efficacy of Multiple Overlapping Uncovered Stents for Endovascular Pararenal Aortic Aneurysm Repair|
- Number of patients with aneurysm exclusion [ Time Frame: 12 months ]Aneurysm exclusion means that the aneurysm shrinks or stays stable over time.
- Number of patent major branches within the coverage zone [ Time Frame: 12 months ]Major branches include the celiac artery, superior mesenteric artery, or renal artery.
- Number of patients with serious adverse events [ Time Frame: 12 months ]Adverse events include aneurysm-related, procedure-related, and stent-related complications or mortality
|Study Start Date:||May 2014|
|Estimated Study Completion Date:||October 2020|
|Estimated Primary Completion Date:||October 2020 (Final data collection date for primary outcome measure)|
Experimental: Pararenal aortic aneurysm
The aneurysm is adjacent to (proximal/distal landing zone < 15mm) or involving vital branches, including the celiac artery, superior mesenteric artery, or renal artery.
The intervention is endovascular management of the aneurysms with multiple overlapping uncovered stents
Procedure: Multiple overlapping uncovered stents
Endovascular management of complex aortic aneurysms with multiple overlapping uncovered stentsDevice: Uncovered stents
The number of uncovered stents implanted was determined by intraoperative angiography with the criterion that a decrease of velocity in the aneurysmal sac was achieved. Side branches, including segmental arteries and visceral branches, were covered wherever necessary.
The traditional endovascular treatment of aneurysms is based on the utilization of stent-grafts that create a mechanical barrier between the aneurysmal sac and normal blood flow. Problems such as endoleak and occlusion of collateral arteries impede its application in complex aneurysms adjacent to or involving vital branches. Advanced branched/fenestrated endografts have been applied in many experienced centers, but the application of these techniques is limited in less-experienced centers due to the complicated and cumbersome nature of these procedures.
The concept of using bare metal stents to occlude aneurysms was firstly described about two decades ago. Geremia et al suggested that a metallic stent bridging a saccular aneurysm would alter the local flow pattern, promoting thrombus formation, thereby leading to aneurysm occlusion. Optimal flow modulation effect is reached with a mean stent porosity of 65%. To achieve such low mesh porosity while maintaining the flexibility of the stent, the investigators applied multiple stents in an overlapping fashion. Computational simulation in this study has demonstrated that with 3 or 4 bare metal stents deployed, the mesh porosity could be decreased to an effective value, slowing flow velocity within the sac. The use of overlapping stents has been reported in the treatment of peripheral aneurysms with satisfactory clinical outcome.
The primary purposes of this study is to evaluate the safety, feasibility, and efficacy of multiple overlapping uncovered stents in treating aortic aneurysm while preserving major visceral branches, including the celiac artery (CA), superior mesenteric artery (SMA) and renal artery (RA).
Please refer to this study by its ClinicalTrials.gov identifier: NCT01985906
|Contact: Qingsheng Lu, MD||+86 021 firstname.lastname@example.org|
|Contact: Yongxue Zhang, MD||+86 email@example.com|
|Division of Vascular Surgery, Changhai Hospital||Recruiting|
|Shanghai, China, 200433|
|Contact: Qingsheng Lu, MD +86 021 31161662 firstname.lastname@example.org|
|Contact: Yongxue Zhang, MD +86 13671856162 email@example.com|
|Principal Investigator: Yongxue Zhang, MD|
|Study Chair:||Qingsheng Lu, MD||Changhai Hospital|
|Principal Investigator:||Yongxue Zhang, MD||Changhai Hospital|