Endovascular Aortic Aneurysm Repair with Stent-Grafts: Experimental Models Can Reproduce Endoleaks
Section snippets
AAA model
All protocols for animal experimentation were approved by the institutional Animal Committee in accordance with guidelines of the Canadian Council on Animal Care. Mongrel dogs were sedated with subcutaneous injection of acepromazine (0.1 mg/kg; Atravet, Ayerst Veterinary Laboratories, Guelph, ON, Canada), glycopyrrolate (0.01 mg/kg; Sabex Inc., Boucherville, QC, Canada), and meperidine (4 mg/kg; Sabex Inc.), and anesthetized with intravenous propofol (4 mg/kg; Diprivan 1%, AstraZeneca Canada,
RESULTS
In the three animals surviving AAA surgery, infrarenal abdominal aortic aneurysms measuring 87 mm (±12 mm) in length and 20 mm (±2 mm) in diameter were created (Fig 1). Angiography and Doppler US showed the presence of type II endoleaks in these three dogs immediately after stentgraft implantation. Leaks persisted at 3-month angiography in two of three dogs (Fig 1). In the third dog, a leak was detected at angiography and US at 3 weeks but not at 3 months; however, evidence of a leak was found
DISCUSSION
The mechanisms leading to endoleaks after EVAR are poorly understood. The development of an AAA animal model reproducing endoleaks is an important step for the study of mechanisms and exploration of potential solutions to prevent endoleaks. Large animals are required to study clinically applicable endovascular tools and their modifications. Aneurysm models created by overdilatation with balloon inflation with/without elastase infusion, or by surgery with venous/arterial patch, have already been
Acknowledgments
The authors thank Jocelyne Lavoie (endovascular procedure and planification), Hélène Héon (veterinarian), and Cédric Schmitt (US image management) for their participation in the animal studies, Guylaine Gevry for her assistance with artwork, and Dr. Guy Allaire, Dr. Lydia Whady, and Robert Spenard, from the Department of pathology of CHUM, for access to histological equipment.
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This project has been funded in part by the Plateforme Technologique du CHUM, Montreal, and by a structuring group grant from Valorisation Recherche Quebec. It now benefits from the CIRREF grant program.
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G.S. is a consultant for Medtronic Canada Ltd. and has identified a potential conflict of interest. None of the other authors have identified a potential conflict of interest.