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Background: Vascular graft infection is a severe cardiovascular complication with high mortality rates. Antibacterial vascular graft coatings are widely used and continue to be improved.Objective: To develop a sealant with antimicrobial effect for Dacron vascular grafts and experimentally test the coating properties.Methods: We used 2 types of vascular grafts: graft No. 1 (plain weave) with initial water permeability of 78.8 ± 2.7 mL/cm2/min and graft No. 2 (2/1 twill + 6/4 satin weave) with water permeability of 549.8 ± 20.7 mL/cm2/min. We developed an original gelatin impregnation technique, tested it using a scanning electron microscopy, and measured water permeability and kink radius. We evaluated the antibacterial activity of vancomycin and gelatin impregnation by the disk diffusion test using media with Staphylococcus aureus ATCC 29213 and Enterococcus faecalis ATCC 29212 and measured inhibition zones after 24-hour incubation. We used samples cut out of grafts with vancomycin-containing (experimental group) and no vancomycin-containing (control group) impregnation.Results: The gelatin coating of the samples is visualized as a thin even film and provides zero water permeability. On the negative side, it increased stiffness and the kink radius. Thanks to vancomycin added to the coating, bacterial growth significantly inhibits: the mean diameter of the growth inhibition zone for Staphylococcus aureus and Enterococcus faecalis was 15.60 ± 0.65 and 14.40 ± 0.66 mm, respectively. The grafts untreated with vancomycin showed no growth inhibition zones.Conclusion: Vascular graft treatment with gelatin impregnation and vancomycin solution is a simple measure to prevent the growth of gram-positive bacteria on vascular grafts. Received 14 November 2022. Revised 15 December 2022. Accepted 19 December 2022. Funding: The work was supported by Russian Science Foundation (project No. 22-15-20005). Conflict of interest: The authors declare no conflict of interest. Contribution of the authorsConception and study design: I.Yu. Zhuravleva, A.A. Shadanov, D.A. SirotaData collection and analysis: A.A. Shadanov, L.M. Samoylova, S.V. Vladimirov, T.P. Timchenko, N.E. Luchnikov, E.V. KarpovaStatistical analysis: A.A. ShadanovDrafting the article: A.A. Shadanov, L.M. Samoylova, T.P. Timchenko, A.G. EdemskiyCritical revision of the article: D.A. Sirota, I.Yu. Zhuravleva, A.V. Bogachev-Prokofiev, A.M. ChernyavskiyFinal approval of the version to be published: A.A. Shadanov, I.Yu. Zhuravleva, L.M. Samoylova, T.P. Timchenko, S.V. Vladimirov, E.V. Karpova, N.E. Luchnikov, D.A. Sirota, A.G. Edemskiy, A.V. Bogachev-Prokofiev, A.M. Chernyavskiy

Objective: To evaluate the performance and short-term capacity of the diepoxy-treated bovine jugular vein conduit in large animals during 6-month follow-up.Methods: Thirteen diepoxy-treated bovine jugular vein conduits were implanted into the pulmonary artery of young mini-pigs. During the follow-up, graft function was tested using transesophageal echocardiography. The animals were withdrawn at 6 months, and the explanted conduits were assessed histologically.Results: All the conduits were successfully implanted without any surgical complications. All the animals survived throughout the follow-up. By the end of the follow-up period, the pressure gradient increased on five animals’ conduits including one case of mismatch between the conduit and the native pulmonary artery, two cases of distal stenosis, and two case of endocarditis. No significant increase in valve regurgitation or conduit thrombosis was observed during the follow-up. In conduits without dysfunction, the structure of the walls and leaflets was intact. A thin fibrous tissue covered the conduit inner wall with complete surface endothelialization. Neither signs of degeneration or calcification nor inflammatory cells were found in the conduit wall or leaflets. Neointima proliferation without calcium deposits was observed in two distally stenosed conduits. Inflammatory cells consisting of multinucleated macrophages, lymphocytes, and histiocytes were found in the adventitia. There were no inflammatory cells in the media or intima, and the leaflets showed no changes.Conclusion: Diepoxy-treated bovine jugular vein demonstrated acceptable performance, good endothelialization, and low tendency to thrombosis and calcium accumulation in the wall and leaflets. Received 31 October 2022. Revised 25 November 2022. Accepted 28 November 2022. Funding: The study was supported by Russian Science Foundation (grant No. 22-25-20102). Conflict of interest: The authors declare no conflict of interest. Contribution of the authorsConception and study design: N.R. Nichay, I.Yu. Zhuravleva, A.V. Bogachev-ProkophievData collection and analysis: N.R. Nichay, Yu.Yu. Kulyabin, I.S. Zykov, E.V. Boyarkin, O.Yu. Malakhova, E.V. Kuznetsova, T.P. Timchenko, Ya.L. Rusakova, I.S. Murashov, A.A. DokuchaevaStatistical analysis: N.R. Nichay, I.Yu. ZhuravlevaDrafting the article: N.R. Nichay, I.Yu. Zhuravleva, Yu.Yu. Kulyabin, I.S. Zykov, E.V. Boyarkin, O.Yu. Malakhova, T.P. Timchenko, Ya.L. Rusakova, I.S. Murashov, A.A. DokuchaevaCritical revision of the article: N.R. Nichay, I.Yu. Zhuravleva, Yu.Yu. Kulyabin, A.A. Dokuchaeva, A.V. Bogachev-ProkophievFinal approval of the version to be published: N.R. Nichay, I.Yu. Zhuravleva, Yu.Yu. Kulyabin, I.S. Zykov, E.V. Boyarkin, O.Yu. Malakhova, E.V. Kuznetsova, T.P. Timchenko, Ya.L. Rusakova, I.S. Murashov, A.A. Dokuchaeva, A.V. Bogachev-Prokophiev

Background. Balloon-expandable prostheses authorized for transcatheter pulmonary valve replacement in the Russian Federation have a barrel-shaped frame, which requires pre-stenting of a native right ventricular outflow tract or a conduit. This increases procedure duration, complicates implantation technique, and increases operation costs. Aim. To develop a self-expandable pulmonary valve model for transcatheter replacement and prepare it for preclinical trials.Methods. The model of a self-expandable pulmonary valve bioprothesis for transcatheter replacement made of nitinol was developed. The leaflets and the lining of the frame were made of porcine pericardium and assembled manually. Radial force testing was performed; valve loading into the delivery system was also tested.Results. According to the results of the tests, the valve biomaterial and the suture sites were not damaged after compression. In 2022, initial preclinical tests are scheduled to determine viability of the implanted valves at 6 and 12 months after surgery, and the rate of calcification for this observation period is to be assessed as well.Conclusion. By optimizing the design of the support frame, we improved the transcatheter model of the biological valve with satisfactory results at the initial stage of preclinical trials. Received 22 April 2022. Revised 5 May 2022. Accepted 11 May 2022. Funding: This work is supported by a grant of the Russian Science Foundation (project No. 21-75-10041). Conflict of interest: Authors declare no conflict of interest. Contribution of the authorsConception and study design: K.A. Rzaeva, T.P. Timchenko, A.N. Arkhipov, N.R. NichayData collection and analysis: A.V. Voitov, N.R. NichayDrafting the article: K.A. Rzaeva, A.V. GorbatykhCritical revision of the article: I.Yu. Zhuravleva, I.A. Soynov, A.V. Bogachev-ProkophievFinal approval of the version to be published: K.A. Rzaeva, T.P. Timchenko, I.Yu. Zhuravleva, A.N. Arkhipov, A.V. Gorbatykh, A.V. Voitov, N.R. Nichay, A.V. Bogachev-Prokophiev, I.A. Soynov