Sealing of polyester prostheses with autologous fibrin glue and bone marrow

Utility of autologous fibrin glue in the donor site of free abdominal flap for breast reconstruction: A randomized controlled study

BACKGROUND

Seroma formation at the donor site is a common complication of breast reconstruction using free abdominal flap. In this study, we assessed the benefits of use of autologous fibrin glue (AFG) at the donor site.

METHODS

This randomized controlled study compared AFG group (n = 61) with commercial fibrin glue (CFG) group (n = 79). Owing to the high volume of AFG (10 mL), AFG group received fibrin glue at both the anastomosis and the donor sites, whereas CFG group received fibrin glue only at the anastomosis site. Operative protocols and the criteria for postoperative drain removal were identical in both groups. Patient characteristics and abdominal discharge were compared between the two groups.

RESULTS

Since anemia was a contraindication for use of AFG, preoperative Hb in CFG group was significantly lower than that in AFG group; other factors were comparable in the two groups. The mean total abdominal drain volumes on first postoperative day (POD1) and POD2 was (AFG vs. CFG) 130.9 vs. 169.4 mL (P < 0.001) and 131.0 vs. 162.8 mL (P = 0.03), respectively. On POD3, there was no significant difference in this respect (116.2 vs. 128.4 mL, P = 0.19). The mean time for removal of all abdominal drains was significantly lower in AFG group (7.4 vs. 8.4 days; P = 0.01).

CONCLUSIONS

AFG reduced the discharge at the donor site of free abdominal flap, especially in the early postoperative period. AFG helped to reduce the abdominal drainage period.

Attachment of human endothelial cells to polyester vascular grafts: pre-coating with adhesive protein assemblies and resistance to short-term shear stress

Cardiovascular prosthetic bypass grafts do not endothelialize spontaneously in humans, and so they pose a thrombotic risk. Seeding with cells improves their performance, particularly in small-caliber applications. Knitted tubular polyethylene-terephthalate (PET) vascular prostheses (6 mm) with commercial type I collagen (PET/Co) were modified in the lumen by the adsorption of laminin (LM), by coating with a fibrin network (Fb) or a combination of Fb and fibronectin (Fb/FN). Primary human saphenous vein endothelial cells were seeded (1.50 × 10(5)/cm2), cultured for 72 h and exposed to laminar shear stress 15 dyn/cm(2) for 40 and 120 min. The control static grafts were excluded from shearing. The cell adherence after 4 h on PET/Co, PET/Co +LM, PET/Co +Fb and PET/Co +Fb/FN was 22%, 30%, 19% and 27% of seeding, respectively. Compared to the static grafts, the cell density on PET/Co and PET/Co +LM dropped to 61% and 50%, respectively, after 120 min of flow. The cells on PET/Co +Fb and PET/Co +Fb/FN did not show any detachment during 2 h of shear stress. Pre-coating the clinically-used PET/Co vascular prosthesis with LM or Fb/FN adhesive protein assemblies promotes the adherence of endothelium. Cell retention under flow is improved particularly on fibrin-containing (Fb and Fb/FN) surfaces.

Improved adhesion and differentiation of endothelial cells on surface-attached fibrin structures containing extracellular matrix proteins

Currently used vascular prostheses are hydrophobic and do not allow endothelial cell (EC) adhesion and growth. The aim of this study was to prepare fibrin (Fb)-based two-dimensional (2D) and three-dimensional (3D) assemblies coated with extracellular matrix (ECM) proteins and to evaluate the EC adhesion, proliferation and differentiation on these assemblies in vitro. Coating of Fb with collagen, laminin (LM), and fibronectin (FN) was proved using the surface plasmon resonance technique. On all Fb assemblies, ECs reached higher cell densities than on polystyrene after 3 and 7 days of culture. Immunoflurescence staining showed better assembly of talin and vinculin into focal adhesion plaques, and also more apparent staining of vascular endothelial cadherin on surface-attached 3D Fb and protein-coated Fb assemblies. On these samples, ECs also contained a lower concentration of intercellular adhesion molecule-1, measured by enzyme-linked immunosorbent assay. Higher concentrations of CD31 (platelet-endothelial cell adhesion molecule-1) were found on 3D Fb coated with LM, and higher concentrations of von Willebrand factor were found on 3D Fb coated with type I collagen or LM in comparison to 2D Fb layers. The results indicate that ECM protein-coated 2D and 3D Fb assemblies can be used for versatile applications in various tissue replacements where endothelialization is desirable, for example, vascular prostheses and heart valves.

Biomechanical and histologic analysis in aortic endoprosthesis using fibrin glue

BACKGROUND

The absence of incorporation between endoprosthesis (EP) and the arterial wall may lead to device migration and endoleaks around the stent graft. Alternatives have been tested aiming to improve this incorporation. Fibrin glue is used in many operating procedures promoting adhesion and tissue regeneration; however, its use to improve EP incorporation by arteries is unknown.

OBJECTIVE

The objective of this study was to analyze dislodgement forces needed to extract the EPs implanted in pig aorta, compare different oversizing and fibrin glue injections, and to analyze histologic changes among groups.

METHODS

Straight EPs were implanted in the thoracic aorta of pigs using 10% oversizing plus fibrin glue in the interface between the EP and the artery (group 1), using 20% oversizing (group 2), and 10% oversizing (group 3). Fourteen days after the implant, the animals were killed to enable biomechanical analysis of the EP and to verify histologic changes of the aortic wall and its interface with the EP.

RESULTS

Group 1 showed a dislodgement force of 21.9 ± 5.3 Newton (N) being higher than the other groups and statistically significant when compared to group 3 (15.6 ± 3.6N), P = .003%. Group 2 had a higher dislodgement force and statistically more significant than group 3 (19.5 ± 7.8N). Histologic analysis showed tissue reaction with inflammatory cells and fibroblasts higher in group 1 and group 2 compared to group 3.

CONCLUSION

This study reports a large animal survival model of thoracic aortic stent graft placement by testing the impact of fibrin glue on EP incorporation. Compared to oversizing alone, fibrin glue placed between the stent graft and the arterial wall increases EP incorporation. Additional studies are needed to determine the potential utility of fibrin glue in the setting of human arterial endografts.

Autologous fibrin-coated small-caliber vascular prostheses improve antithrombogenicity by reducing immunologic response

OBJECTIVE

We have recently developed a thrombin-free fibrin-coated vascular prosthesis that has a high performance rate in producing graft antithrombogenicity. We hypothesized that autologous, compared with xenologous, fibrin coatings could improve the antithrombogenicity of grafts by reducing immunologic response.

METHODS

Autologous fibrin-coated vascular prostheses and/or xenologous fibrin-coated vascular prostheses (internal diameter, 2 mm; length, 2.5 cm) were implanted in the bilateral carotid arteries of 50 Japanese white rabbits. They were classified into 2 groups by the selection of grafts in the individual: group I (autologous fibrin-coated vascular prosthesis and xenologous fibrin-coated vascular prosthesis); and group II (group IIa: both autologous fibrin-coated vascular prostheses, or group IIx: both xenologous fibrin-coated vascular prostheses). During a maximum of 180 days after implantation, we evaluated the thrombotic, inflammatory, and immunologic responses associated with both types of graft.

RESULTS

All grafts were patent at each end point. In group I, both platelet deposition and anti-graft antibodies in autologous fibrin-coated vascular prostheses were significantly less than those in xenologous fibrin-coated vascular prostheses until postoperative day 30. At postoperative day 10, there were significantly fewer CD45-positive infiltrating cells in autologous fibrin-coated vascular prostheses, and intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and nuclear factor-kappa B expression in autologous fibrin-coated vascular prostheses were less than those in xenologous fibrin-coated vascular prostheses. The neointimal hyperplasia in autologous fibrin-coated vascular prostheses was significantly decreased at postoperative day 180. In group II, serial changes of serum levels of immunoglobulin M, immunoglobulin G, interleukin-1beta, and tissue-type plasminogen activator/plasminogen activator inhibitor-1 ratio in autologous fibrin-coated vascular prostheses were significantly less than those in xenologous fibrin-coated vascular prostheses. In both grafts, platelet deposition significantly correlated with serum immunoglobulin G level and tissue-type plasminogen activator/plasminogen activator inhibitor-1 ratio.

CONCLUSION

These findings suggest that autologous fibrin coating in thrombin-free fibrin-coated vascular prostheses improve antithrombogenicity by reducing immunologic response and have a potential for clinical use in hybrid small-caliber vascular grafts.

Indium-111-oxine-labeled platelet scintigraphic images in the assessment of thrombogenicity in small-caliber prosthetic vascular grafts

Anti-thrombogenicity is one of the essential factors for successful development of small-caliber prosthetic vascular grafts, and its accurate evaluation is important. The purpose of this study was to investigate the efficacy of indium-111-oxine-labeled (In) platelet scintigraphic images in the assessment of graft thrombogenicity. Fibrin-coated knitted polyester vascular prostheses, 2 mm in diameter and 2 cm in length, were implanted in the bilateral common carotid arteries of 18 Japanese white rabbits. The grafts were explanted on postoperative days 1, 3, 7, 10, 14, and 30 (six grafts on each of the days), and In platelet scintigraphy was performed with visual, semiquantitative, and quantitative analysis. The relationships among the three analyses were evaluated. Platelet depositions on the luminal surface were clearly visualized with In-platelet scintigraphy if the number of In platelets was more than 4.8 x 10 counts per minute, even if a macroscopic thrombus formation was not observed. There was a highly significant correlation between the graft region of interest on the images and the total platelet deposition (p<.0001). The images in the thrombotic grafts have shown a very strong In-platelet accumulation, but there were some limitations in the In-platelet scintigraphic images. In-platelet scintigraphic images are useful for evaluating platelet deposition in small-caliber vascular prostheses if they are performed with a proper understanding of their limitations.

Thrombin-free Fibrin Coating on Small Caliber Vascular Prostheses Has High Antithrombogenicity in Rabbit Model

Fibrin coatings on prosthetic vascular graft, which are conventionally produced by fibrinogen and thrombin, are expected to improve antithrombogenicity and healing characteristics. Thrombin is one of the factors of blood coagulation cascade; however, it has a possibility to play a negative role in the graft antithrombogenicity. The purpose of this study was to evaluate the performance of our new grafts, thrombin-free fibrin-coated small caliber vascular prostheses. Knitted polyester fabric vascular prostheses 2 mm in internal diameter were coated with fibrin coating with thrombin (Graft I) or without thrombin (Graft II). Both grafts were implanted in bilateral common carotid arteries of 35 Japanese white rabbits, with Graft I in one side and Graft II in the contralateral side. Graft patency, histology, thrombin activity, and platelet deposition were compared between both grafts on postoperative days (PODs) 1, 3, 7, 10, 14, 30, and 60. Both grafts were patent without thrombus or stenosis at each end point (maximal period, POD 60). Macro- and microscopic findings revealed that no obvious difference was observed between both grafts. Before graft implantation, thrombin activities in Grafts I and II were 0.711 +/- 0.086 and 0.009 +/- 0.007 optical density at 405 nm, respectively. Thrombin activity of Graft II was significantly less than that of Graft I in every period after graft implantation, and platelet deposition of Graft II was significantly less than that of Graft I until POD 30. Thrombin-free fibrin-coated vascular prostheses have superior performance of antithrombogenicity to conventional fibrin-coated vascular prostheses with thrombin.