Fatemeh Zehtabi1,2, Vincent Dumont-Mackay3, Ahmed Fatimi1,2,4, Antony Bertrand-Grenier2,5, Hélène Héon2, Gilles Soulez2,5, Sophie Lerouge6,7,8. 1. Department of Mechanical Engineering, École de technologie supérieure, 1100 Notre-Dame Street West, Montreal, QC, H3C 1K3, Canada. 2. Research Centre, Centre Hospitalier de l'Université de Montréal (CRCHUM), 900 St Denis, Tour Viger, Montreal, QC, H2X 0A9, Canada. 3. Département de pathologie, Centre hospitalier de l'Université de Montréal, Montreal, Canada. 4. Faculté Polydisciplinaire, Department of Chemistry, Université Sultan Moulay Slimane, Mghila BP:592, 23000, Beni-Mellal, Morocco. 5. Department of Radiology, Université de Montréal, Montreal, QC, H2L 4M1, Canada. 6. Department of Mechanical Engineering, École de technologie supérieure, 1100 Notre-Dame Street West, Montreal, QC, H3C 1K3, Canada. Sophie.lerouge@etsmtl.ca. 7. Research Centre, Centre Hospitalier de l'Université de Montréal (CRCHUM), 900 St Denis, Tour Viger, Montreal, QC, H2X 0A9, Canada. Sophie.lerouge@etsmtl.ca. 8. Department of Radiology, Université de Montréal, Montreal, QC, H2L 4M1, Canada. Sophie.lerouge@etsmtl.ca.
Abstract
PURPOSE: To compare the efficacy of an embolization agent with sclerosing properties (made of chitosan and sodium tetradecyl sulfate, CH-STS) with a similar embolization agent but without sclerosing properties (made of chitosan, CH) in treating endoleaks in a canine endovascular aneurysm repair model. METHODS: Two chitosan-based radiopaque hydrogels were prepared, one with STS and one without STS. Their rheological, injectability, and embolizing properties were assessed in vitro; afterwards, their efficacy in occluding endoleaks was compared in a canine bilateral aneurysm model reproducing type I endoleaks (n = 9 each). The primary endpoint was endoleak persistence at 3 or 6 months, assessed on a CT scan and macroscopic examination. Secondary endpoints were the occurrence of stent-graft (SG) thrombosis, the evolution of the aneurysm mean diameter, as well as aneurysm healing and inflammation scores in pathology examinations. RESULTS: In vitro experiments showed that both products gelled rapidly and presented initial storage moduli greater than 800 Pa, which increased with time. Both gels were compatible with microcatheter injection and occlude flow up to physiological pressure in vitro. In a type I endoleak model, the injection of CH-STS sclerosing gel tended to reduce the risk of occurrence of endoleaks, compared to CH non-sclerosing agent (2/9 vs. 6/9, p = 0.069). No case of SG thrombosis was observed. Moderate inflammation was found around both gels, with a comparable intensity score in both CH and CH-STS groups (2.6 ± 0.9 and 2.7 ± 0.9, respectively; p = 0.789). CONCLUSIONS: Flow occlusion combined with chemical endothelial denudation appears promising for the treatment of endoleaks. LEVEL OF EVIDENCE: N/A.
PURPOSE: To compare the efficacy of an embolization agent with sclerosing properties (made of chitosan and sodium tetradecyl sulfate, CH-STS) with a similar embolization agent but without sclerosing properties (made of chitosan, CH) in treating endoleaks in a canineendovascular aneurysm repair model. METHODS: Two chitosan-based radiopaque hydrogels were prepared, one with STS and one without STS. Their rheological, injectability, and embolizing properties were assessed in vitro; afterwards, their efficacy in occluding endoleaks was compared in a canine bilateral aneurysm model reproducing type I endoleaks (n = 9 each). The primary endpoint was endoleak persistence at 3 or 6 months, assessed on a CT scan and macroscopic examination. Secondary endpoints were the occurrence of stent-graft (SG) thrombosis, the evolution of the aneurysm mean diameter, as well as aneurysm healing and inflammation scores in pathology examinations. RESULTS: In vitro experiments showed that both products gelled rapidly and presented initial storage moduli greater than 800 Pa, which increased with time. Both gels were compatible with microcatheter injection and occlude flow up to physiological pressure in vitro. In a type I endoleak model, the injection of CH-STS sclerosing gel tended to reduce the risk of occurrence of endoleaks, compared to CH non-sclerosing agent (2/9 vs. 6/9, p = 0.069). No case of SG thrombosis was observed. Moderate inflammation was found around both gels, with a comparable intensity score in both CH and CH-STS groups (2.6 ± 0.9 and 2.7 ± 0.9, respectively; p = 0.789). CONCLUSIONS: Flow occlusion combined with chemical endothelial denudation appears promising for the treatment of endoleaks. LEVEL OF EVIDENCE: N/A.