Document Detail

Knitted nitinol represents a new generation of constrictive external vein graft meshes.
MedLine Citation:
PMID:  21802240     Owner:  NLM     Status:  MEDLINE    
OBJECTIVE: Constriction of vein grafts with braided external nitinol meshes had previously led to the successful elimination of neointimal tissue formation. We investigated whether pulse compliance, smaller kink-free bending radius, and milder medial atrophy can be achieved by knitting the meshes rather than braiding, without losing the suppressive effect on intimal hyperplasia.
METHODS: Pulse compliance, bending stiffness, and bending radius, as well as longitudinal-radial deformation-coupling and radial compression, were compared in braided and knitted nitinol meshes. Identical to previous studies with braided mesh grafts, a senescent nonhuman primate model (Chacma baboons; bilateral femoral interposition grafts/6 months) mimicking the clinical size mismatch between vein grafts and runoff arteries was used to examine the effect of knitted external meshes on vein grafts: nitinol mesh-constricted (group 1); nitinol mesh-constricted and fibrin sealant (FS) spray-coated for mesh attachment (group 2); untreated control veins (group 3), and FS spray-coated control veins (group 4).
RESULTS: Compared with braided meshes, knitted meshes had 3.8-times higher pulse compliance (3.43 ± 0.53 vs 0.94 ± 0.12%/100 mm Hg; P = .00002); 30-times lower bending stiffness (0.015 ± 0.002 vs 0.462 ± 0.077 Nmm(2); P = .0006); 9.2-times narrower kink-free bending radius (15.3 ± 0.4 vs 140.8 ± 22.4 mm; P = .0006), and 4.3-times lower radial narrowing caused by axial distension (18.0% ± 1.0% vs 77.0% ± 3.7%; P = .00001). Compared with mesh-supported grafts, neointimal tissue was 8.5-times thicker in group I (195 ± 45 μm) vs group III (23.0 ± 21.0 μm; P < .001) corresponding with a 14.3-times larger neointimal area in group I (4330 ± 957 × 103 μm(2)) vs group III (303 ± 221× 103 μm(2); P < .00004). FS had no significant influence. Medial muscle mass remained at 43.4% in knitted meshes vs the 28.1% previously observed in braided meshes.
CONCLUSION: Combining the suppression of intimal hyperplasia with a more physiologic remodeling process of the media, manifold higher kink-resistance, and lower fraying than in braided meshes makes knitted nitinol an attractive concept in external vein graft protection.
Peter Zilla; Loven Moodley; Michael F Wolf; Deon Bezuidenhout; Mazin S Sirry; Nasser Rafiee; Wilhelm Lichtenberg; Melanie Black; Thomas Franz
Publication Detail:
Type:  Comparative Study; Journal Article; Research Support, Non-U.S. Gov't     Date:  2011-07-29
Journal Detail:
Title:  Journal of vascular surgery     Volume:  54     ISSN:  1097-6809     ISO Abbreviation:  J. Vasc. Surg.     Publication Date:  2011 Nov 
Date Detail:
Created Date:  2011-10-26     Completed Date:  2011-12-15     Revised Date:  2014-09-21    
Medline Journal Info:
Nlm Unique ID:  8407742     Medline TA:  J Vasc Surg     Country:  United States    
Other Details:
Languages:  eng     Pagination:  1439-50     Citation Subset:  IM    
Copyright Information:
Copyright © 2011 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Biomechanical Phenomena
Equipment Design
Femoral Artery / physiopathology,  surgery*,  ultrastructure
Femoral Vein / physiopathology,  transplantation*,  ultrastructure
Fibrin Tissue Adhesive
Materials Testing
Microscopy, Electron, Scanning
Models, Animal
Papio ursinus
Pulsatile Flow
Surgical Mesh*
Time Factors
Vascular Grafting / adverse effects,  instrumentation*
Grant Support
Reg. No./Substance:
0/Alloys; 0/Fibrin Tissue Adhesive; 52013-44-2/nitinol

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Endovascular therapy for infected aortic aneurysms.
Next Document:  Thrombolysis for deep venous thrombosis.