Novel Sclerosing and Embolizing Gel for Varicose Vein Treatment: Feasibility Study in a Porcine Model

Wednesday, March 8, 2023

4:12 PM – 4:21 PM

Location: Phoenix Convention Center, 225AB

Abstract Speaker(s)

Jamal Ait ichou, MD

Resident
McGill University

Disclosure(s): COOK Medical: Intellectual Property / Patents (), Research Grant or Support ()

Author/Co-author(s)

FM

Fanny Morin-Roy, MD

Medical student
Université de Laval
SA

Samy-Yanis Amer-youcef, Medical student

Student
Université de Sherbrooke
WT

Werner Taillades, BsC

Master's student
École de technologie supérieure (ÉTS)
SL

Sophie Lerouge, PhD, Eng

Full professor
Centre de recherche du CHUM (CrCHUM) and École de technologie supérieure (ÉTS)
Gilles Soulez, MD MSc FSIR (he/him/his)

Professor
CHUM

Disclosure(s):

Jamal Ait ichou, MD: COOK Medical: Intellectual Property / Patents (), Research Grant or Support ()

Gilles Soulez, MD MSc FSIR: bard medical: Contracted Research (Ongoing); Cook Medical: Consultant (Ongoing), Intellectual Property Rights (Ongoing), Research Grant Recipient (Ongoing); R3 Vascular: Contracted Research (Ongoing); Siemens Medical: Research Grant Recipient (Ongoing); Starpax: Consultant (Ongoing), Research Grant Recipient (Ongoing); Vitaa Medical: Advisory Committee or Review Panel Member (Ongoing), Consultant (Ongoing), Contracted Research (Ongoing), Research Grant Recipient (Ongoing)

Purpose:

Venous recanalization is the main limitation following embolization of venous insufficiency {1-3}. Combining endothelial ablation and mechanical occlusion yields more durable vascular occlusion {4, 5}. We developed a temporarily radio-opaque, sclerosing and embolizing gel composed of chitosan and a sclerosant agent (Sodium Tetradecyl Sulfate (CH-STS)) and tested the feasibility of venous embolization using CH-STS in a porcine model.

Materials and Methods:

In 15 pigs, the internal maxillary (IMV) and the inferior gluteal veins (IGV) were embolized. For 9 animals (group 1), The IMV was first embolized proximally with 2 coils before injecting the gel distally with a micro catheter, and no coil was inserted in the IGV. Six animals had gel injection and coiling only in the IMV (group 2, n=3) or in the IGV (group 3, n=3). Vein thrombosis was assessed by DSA and CBCT and gel migration in the lung by CBCT at D0 and D30. Histological analysis of injected veins was performed.

Results:

Gel embolization was successful in all veins with no catheter adhesion. Mean Likert score for radiopacity at D0 was 4.8/5, and for injectability 3.8/5. Gel was no longer radiopaque at D30.

At D0, only one animal had minimal gel migration in the lung (IMV group 1).

At D30, coil migration was observed in 6/12 (50%) IMVs (group 1, 2). Complete thrombosis on imaging was observed in 11/12 (92 %) IMVs (group 1 and 2). One animal with coil and gel migration had a patent IMV. In the IGVs, coil migration was observed in all 3 animals (group 3) and complete thrombosis on imaging was observed in 9/12 (75%) (group 1, 3); three animals with coil and gel migration had permeable IGVs.

For all groups, quality of thrombosis on histology and presence of gel in the vein was higher with coil protection and absence of coil migration (see table). Gel migration in the lung at D30 was observed in 14/15 animals with higher PE score in presence of coil migration (mean: 5.3 vs 4.1). The only animal with no coil migration and no IGV embolization had no gel migration in the lung.

Conclusion:

The CH-STS gel is easily injectable, transiently radiopaque and presents no risk of catheter adhesion. The swine IMV /IGV embolization model is challenging as it induces a high rate of gel and coil migration. Coil protection minimizes the risk of gel migration. Further tests in a model reproducing flow condition of varicose veins are need.