Vascular graft infections:In vitro andin vivo investigations of a new vascular graft with long-term protection

2005 ◽  
Vol 74B (1) ◽  
pp. 601-607 ◽  
Author(s):  
Torsten Ueberrueck ◽  
Roland Zippel ◽  
Joerg Tautenhahn ◽  
Ingo Gastinger ◽  
Hans Lippert ◽  
...  
Keyword(s):  
2019 ◽  
Author(s):  
Hugo Krynauw ◽  
Jannik Buescher ◽  
Josepha Koehne ◽  
Loes Verrijt ◽  
Georges Limbert ◽  
...  

AbstractPurposeThe lack of long-term patency of synthetic vascular grafts currently available on the market has directed research towards improving the performance of small diameter grafts. Improved radial compliance matching and tissue ingrowth into the graft scaffold are amongst the main goals for an ideal vascular graft.MethodsBiostable polyurethane scaffolds were manufactured by electrospinning and implanted in subcutaneous and circulatory positions in the rat for 7, 14 and 28 days. Scaffold morphology, tissue ingrowth, and mechanical properties of the scaffolds were assessed before implantation and after retrieval.ResultsTissue ingrowth after 24 days was 96.5 ± 2.3% in the subcutaneous implants and 77.8 ± 5.4% in the circulatory implants. Over the 24 days implantation, the elastic modulus at 12% strain decreased by 59% in direction of the fibre alignment whereas it increased by 1379% transverse to the fibre alignment of the highly aligned scaffold of the subcutaneous implants. The lesser aligned scaffold of the circulatory graft implants exhibited an increase of the elastic modulus at 12% strain by 77% in circumferential direction.ConclusionBased on the observations, it is proposed that the mechanism underlying the softening of the highly aligned scaffold in the predominant fibre direction is associated with scaffold compaction and local displacement of fibres by the newly formed tissue. The stiffening of the scaffold, observed transverse to highly aligned fibres and for more a random fibre distribution, represents the actual mechanical contribution of the tissue that developed in the scaffold.


2019 ◽  
Vol 58 (6) ◽  
pp. e817-e818 ◽  
Author(s):  
Guriy Popov ◽  
Valeriy Vavilov ◽  
Galina Yukina ◽  
Pavel Popryadukhin ◽  
Irina Dobrovolskaya ◽  
...  
Keyword(s):  

Author(s):  
Brian M. Leoce ◽  
Herbert Dardik ◽  
Phillip Bahramipour ◽  
Thomas R. Bernik
Keyword(s):  

2010 ◽  
Vol 51 (1) ◽  
pp. 155-164 ◽  
Author(s):  
Soichiro Enomoto ◽  
Makoto Sumi ◽  
Kan Kajimoto ◽  
Yasumoto Nakazawa ◽  
Rui Takahashi ◽  
...  

2006 ◽  
Vol 72 (12) ◽  
pp. 1168-1175 ◽  
Author(s):  
Norma M. Edwards ◽  
Jeffrey A. Claridge ◽  
Dan H. Shell ◽  
Charles R. Handorf ◽  
Martin A. Croce ◽  
...  

Neointimal hyperplasia (NH) is the most significant contributing factor to long-term vascular graft failure. Inflammation is known to be important in its development; however, the role of bacterial infection is unclear. We examined the effect of contamination with common organisms on the development of NH in expanded polytetrafluoroethylene grafts. Thirty adult pigs were randomized into one of four groups: no infection, contamination with Staphylococcus aureus, mucin-producing Staphylococcus epidermidis, or Pseudomonas aeruginosa. An expanded polytetrafluoroethylene graft (6 mm x 3 cm) was placed as a common iliac artery interposition graft and was inoculated with 1–2 x 108 of the selected organism before closure. Grafts were explanted 6 weeks postoperatively. Microbiologic, histological, and morphometric evaluations were performed. All grafts were patent at the time of euthanasia. The mean areas of NH were 5.45 mm2 in sterile grafts, 8.36 mm2 in S. aureus, 7.63 mm2 in S. epidermidis, and 11.52 mm2 in P. aeruginosa grafts. Comparison of means via analysis of variance showed that P. aeruginosa grafts had significantly higher formation of NH than sterile grafts (P = 0.025). NH production in infected grafts appears to be organism specific and is significantly higher with P. aeruginosa than common Gram-positive organisms. Increased NH from subclinical infection may be a significant factor contributing to late graft failures.


2020 ◽  
Vol 41 (43) ◽  
pp. 4181-4187 ◽  
Author(s):  
Mitzi M van Andel ◽  
Reza Indrakusuma ◽  
Hamid Jalalzadeh ◽  
Ron Balm ◽  
Janneke Timmermans ◽  
...  

Abstract Aims The COMPARE trial showed a small but significant beneficial effect of 3-year losartan treatment on aortic root dilatation rate in adults with Marfan syndrome (MFS). However, no significant effect was found on clinical endpoints, possibly due to a short follow-up period. The aim of the current study was therefore to investigate the long-term clinical outcomes after losartan treatment. Methods and results In the original COMPARE study (inclusion 2008–2009), adult patients with MFS (n = 233) were randomly allocated to either the angiotensin-II receptor blocker losartan® on top of regular treatment (β-blockers in 71% of the patients) or no additional medication. After the COMPARE trial period of 3 years, study subjects chose to continue their losartan medication or not. In a median follow-up period of 8 years, 75 patients continued losartan medication, whereas 78 patients, originally allocated to the control group, never used losartan after inclusion. No differences existed between baseline characteristics of the two groups except for age at inclusion [losartan 34 (interquartile range, IQR 26–43) years, control 41 (IQR 30–52) years; P = 0.031], and β-blocker use (losartan 81%, control 64%; P = 0.022). A pathological FBN1 mutation was present in 76% of patients and 58% of the patients were male. Clinical endpoints, defined as all-cause mortality, aortic dissection/rupture, elective aortic root replacement, reoperation, and vascular graft implantation beyond the aortic root, were compared between the two groups. A per-patient composite endpoint was also analysed. Five deaths, 14 aortic dissections, 23 aortic root replacements, 3 reoperations, and 3 vascular graft implantations beyond the aortic root occurred during follow-up. Except for aortic root replacement, all endpoints occurred in patients with an operated aortic root. Patients who used losartan during the entire follow-up period showed a reduced number of events compared to the control group (death: 0 vs. 5, P = 0.014; aortic dissection: 3 vs. 11, P = 0.013; elective aortic root replacement: 10 vs. 13, P = 0.264; reoperation: 1 vs. 2, P = 0.463; vascular graft implantations beyond the aortic root 0 vs. 3, P = 0.071; and composite endpoint: 14 vs. 26, P = 0.019). These results remained similar when corrected for age and β-blocker use in a multivariate analysis. Conclusion These results suggest a clinical benefit of combined losartan and β-blocker treatment in patients with MFS.


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