title: Assessment of ischemia-induced microvascular remodeling using contrast-enhanced ultrasound vascular anatomic mapping.
abstract: Our aim was to apply novel contrast-enhanced ultrasound (CEU) techniques to characterize remodeling in different vascular compartments during ischemia-mediated angiogenesis. Hind limb ischemia was produced by ligation of an external iliac artery in 60 rats, half of which were treated with intramuscular fibroblast growth factor (FGF)-2 (5 microg). The proximal adductor muscles of the ischemic and control hind limb were studied immediately after ligation and at days 4, 7, or 14. Low-power maximum intensity projection imaging was performed to assess large intramuscular vessels to the fourth branch order. CEU data were analyzed to measure capillary perfusion and functional noncapillary microvascular blood volume. Resting capillary perfusion was reduced by 30% after arterial ligation and recovered earlier in FGF-2-treated versus nontreated rats (day 4 vs. 14). Changes in perfusion were temporally related to expansion of noncapillary microvascular blood volume on CEU, which was associated with an arteriogenic response on histology. Expansion of and organization (fractal distribution) of large collateral vessels occurred gradually over 2 weeks and was slightly more rapid with FGF-2 treatment. We conclude that CEU can separately assess collateral development, more distal arteriogenesis, and secondary changes in capillary perfusion that occur differentially with ischemia and growth factor therapy.
authors.affiliation: Cardiovascular Division, University of Virginia, Charlottesville, Virginia, USA.
authors.forename: Marco
authors.initials: M
authors.lastname: Pascotto
authors.forename: Howard
authors.initials: H
authors.lastname: Leong-Poi
authors.forename: Beat
authors.initials: B
authors.lastname: Kaufmann
authors.forename: Achim
authors.initials: A
authors.lastname: Allrogen
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Charalampidis
authors.forename: Edmund K
authors.initials: EK
authors.lastname: Kerut
authors.forename: Sanjiv
authors.initials: S
authors.lastname: Kaul
authors.forename: Jonathan R
authors.initials: JR
authors.lastname: Lindner
mesh_terms: D000222:Adaptation, Physiological; D000704:Analysis of Variance; D000818:Animals; D001158:Arteries / Q000000981:diagnostic imaging* / Q000187:drug effects* / Q000254:growth & development; D001783:Blood Flow Velocity; D003097:Collateral Circulation / Q000187:drug effects; D003287:Contrast Media; D005346:Fibroblast Growth Factors / Q000494:pharmacology*; D006614:Hindlimb / Q000098:blood supply; D007091:Image Processing, Computer-Assisted; D007150:Immunohistochemistry; D007511:Ischemia / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008026:Ligation; D008297:Male; D018482:Muscle, Skeletal / Q000098:blood supply; D018919:Neovascularization, Physiologic / Q000187:drug effects*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors; D014463:Ultrasonography
chemical_list: D003287:Contrast Media; D005346:Fibroblast Growth Factors