Abdominal Aortic Aneurysm Follow-up After Endovascular Repair by Non-invasive Vascular Elastography (AAA-Elasto)
|Aortic Aneurysm Abdominal Endovascular Aneurysm Repair (EVAR)||Other: QSE-LSME - SSWI Ultrasound|
|Study Design:||Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Diagnostic
|Official Title:||Abdominal Aortic Aneurysm Follow-up After Endovascular Repair by Non-invasive Vascular Elastography|
- QSE-LSME [ Time Frame: Day 0: When the elastographic examinations (QSE-LSME, SSWI) and CT-scan will be completed ]We will compare strain values of the different AAA components in the three groups Then, we will test the best combination of strain criteria defined in the preclinical optimization and validation phase among three groups to evaluate if we can define a threshold to discriminate the 3 groups.
- SSWI [ Time Frame: Day 0: When the elastographic examinations (QSE-LSME, SSWI) and CT-scan will be completed ]Elasticity values of the aortic wall and thrombus in systolic and diastolic phase will be compared in the 3 groups
|Study Start Date:||January 2014|
|Estimated Study Completion Date:||March 2018|
|Estimated Primary Completion Date:||December 2017 (Final data collection date for primary outcome measure)|
QSE-LSME and SSWI ultrasound
QSE-LSME and SSWI ultrasound examinations combined with a clinically required CT-scan. We will screen 3 groups of 15 patients each, with at least one-year follow-up after EVAR, matched for sex, age and aneurysm diameter at baseline (before EVAR).
Group 1. Patients without endoleak and a maximal diameter reduction at one year of at least 10% and a volume reduction of 20%.
Group 2. Patients with a stable sac volume and diameter (less than 10% volume and 5% diameter variation within a year).
Group 3. Patients with type I, type II or type V endoleak (endotension) with more than 10% diameter progression and 20% volume progression.
Other: QSE-LSME - SSWI Ultrasound
Doppler ultrasound (DUS) and elastographic examinations will be performed using a single probe (6-1 MHz, Super Curved, Vermon, Tours, France) with the clinical Aixplorer system (Supersonic Imagine, Aix-en-Provence, France), a new generation ultrasound scanner providing an outstanding B-mode and color-Doppler image quality, allowing exportation of RF images for QSE-LSME acquisition and integrating the shear wave elastography (SSWI) mode.
Experimental protocol: Optimization and validation of these 2 techniques will be completed in 3 experimental phases:
- Preclinical validation: Abdominal aortic aneurysm and EVAR without endoleak (n=6), with a type I (n=6) and a type II (n=6) endoleak will be created in 18 mongrel dogs. QSE-LSME and SSWI acquisitions will be acquired before SG insertion and at 48H, 1, 3 months and at sacrifice at 6 months. The 2 techniques will be optimized to generate strain (QSE-LSME) and elasticity (SSWI) measurements of the simulated thrombus and vessel wall. CT-scan with prospective gating will be acquired on the AAA at least 6 different cardiac phases then segmented to allow 2D/3D registration of CT and elastographic acquisitions. Strain (QSE-LSME) and elasticity (SSWI) measurements of sac thrombus and vessel wall will be compared in the three experimental groups and correlated to sac pressure measurements, CT segmentation of sac components and pathologic evaluation.
- Clinical feasibility, reproducibility and correlation with CT-angiography. From our EVAR database, 3 groups of 15 patients will be selected based on clinical and CT-angiography evolution. Group 1 will include patients without endoleak and AAA volume decrease of more than 20% following EVAR, group 2 patients without endoleak and no more than 10% sac volume variation and group 3 patients with endoleak or endotension and more than 20% sac volume increase. Ultrasound B-mode RF acquisitions with QSE-LSME and SSWI techniques will be acquired by two independent investigators. We will compare strain values of the different AAA components in the three groups. Thresholds will be tested to detect endoleak. Then strain values will be correlated with diameter, volume and stretch index variation between baseline and contemporary CT scans.
- Prospective study validation of strain elasticity thresholds for endoleak detection and characterization of thrombus organization. The goal of this second clinical feasibility study is to collect longitudinal strain and elasticity measurements in the early post EVAR period (before one-year). We will include 15 patients with AAA scheduled for EVAR. These patients will have a baseline CT and baseline QSE-LSME and SSWI examination. Doppler ultrasound with QSE-LSME and SSWI examinations will then be performed at 3 and 12 months. The variation of strain and elastic values over time frames will be analyzed and correlated volume progression and endoleak occurrence on CT scans.
Please refer to this study by its ClinicalTrials.gov identifier: NCT01907386
|Contact: Dominique Aubin, MSc||(514) 890-8000 ext firstname.lastname@example.org|
|Contact: Jennifer Satterthwaite, M.Sc||(514) 890-8000 ext email@example.com|
|Centre Hospitalier de l'Université de Montréal (CHUM)||Recruiting|
|Montréal, Quebec, Canada, H2L 4M1|
|Contact: Dominique Aubin, MSc 514-890-8000 ext 30598 firstname.lastname@example.org|
|Principal Investigator: Gilles Soulez, MD, M.Sc|
|Principal Investigator:||Gilles Soulez, MD, M.Sc||Centre hospitalier de l'Université de Montréal (CHUM)|