title: Measurement of collateral blood flow in a porcine model of aortic coarctation by velocity-encoded cine MRI.
abstract: The purpose of this study was to investigate the time course of development of collateral blood flow in an animal model of aortic coarctation. A juxtaductal aortic stenosis (model coarctation) was surgically created in five juvenile pigs. MRI was performed preoperatively, 1 to 2 days postoperatively, and 2 to 10 weeks postoperatively. Aortic blood flow was measured by velocity-encoded cine MR (VENC-MR). The percent change in aortic blood flow (delta BF) from proximal to distal descending thoracic aorta was calculated, and a multiple-comparison paired t test used to assess changes in delta BF over time. Invasive flow measurements were obtained in one animal before sacrifice using an ultrasonic probe. delta BF preoperatively was -2 +/- 8% (mean +/- SE). delta BF increased to 32 +/- 7% (mean +/- SE, P = .022) 2 days postoperatively and 55 +/- 19% (P = .032) 2 to 8 weeks postoperatively. Invasive measurements were in qualitative agreement with the VENC-MR data. VENC-MR is an accurate noninvasive method of measuring collateral blood flow in aortic coarctation. Recruitment and development of collateral flow pathways occur rapidly in an animal model.
authors.affiliation: Department of Radiology, University of California at San Francisco 94143, USA.
authors.forename: D M
authors.initials: DM
authors.lastname: Chernoff
authors.forename: N
authors.initials: N
authors.lastname: Derugin
authors.forename: H A
authors.initials: HA
authors.lastname: Rajasinghe
authors.forename: F L
authors.initials: FL
authors.lastname: Hanley
authors.forename: C B
authors.initials: CB
authors.lastname: Higgins
authors.forename: C A
authors.initials: CA
authors.lastname: Gooding
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001017:Aortic Coarctation / Q000175:diagnosis* / Q000503:physiopathology*; D001783:Blood Flow Velocity; D003097:Collateral Circulation / Q000502:physiology*; D004195:Disease Models, Animal; D007090:Image Interpretation, Computer-Assisted; D019028:Magnetic Resonance Imaging, Cine; D012680:Sensitivity and Specificity; D013552:Swine