A reproducible porcine ePTFE arterial bypass model for neointimal hyperplasia.
BACKGROUND
Late failure of prosthetic vascular bypass grafting using expanded polytetrafluoroethylene (ePTFE) is secondary to the development of neointimal hyperplasia, most commonly at the distal anastomosis. To develop therapies that can improve upon current prosthetic vascular bypass grafting, a large animal model of prosthetic bypass grafting that results in reproducible neointimal hyperplasia is necessary.


METHODS
We performed bilateral end-to-side carotid artery bypasses with 6 mm ePTFE in a porcine model (n = 11). We studied graft patency using magnetic resonance angiography (MRA, 3 wk), duplex ultrasonography (4 wk), and digital-subtraction contrast angiography (4 wk). Animals were sacrificed at 4 wk and morphometric analysis was performed.


RESULTS
Of the 11 animals that underwent surgery, one pig died from respiratory compromise; of the remaining 10, graft patency was 90% at 4 wk. Peak systolic and end diastolic velocities were established for this model using ultrasonography. MRA, ultrasonography, and angiography confirmed graft patency and were complimentary tools to evaluate the grafts. Development of neointimal hyperplasia was reproducible at 4 wk in both the proximal and distal anastomoses (2.5 to 3 mm(2)) of the ePTFE bypass grafts.


CONCLUSIONS
We developed a reproducible porcine ePTFE carotid artery bypass model for studying neointimal hyperplasia. Not only does this model allow for the manipulation and evaluation of potential therapies, but patency and neointimal hyperplasia can be easily evaluated by traditional means, such as MRA, ultrasonography, and angiography. This preclinical model is ideal for evaluation of novel therapies in vivo designed to inhibit neointimal hyperplasia following arterial reconstruction with prosthetic bypass grafting.
Kapadia
Muneera R
MR
Division of Vascular Surgery, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA.
Aalami
Oliver O
OO
Najjar
Samer F
SF
Jiang
Qun
Q
Murar
Jozef
J
Lyle
Brian
B
Eng
Jason W
JW
Kane
Bonnie
B
Carroll
Timothy
T
Cahill
Patricia M
PM
Kibbe
Melina R
MR
D000818:Animals; D001807:Blood Vessel Prosthesis; D002339:Carotid Arteries / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery*; D004195:Disease Models, Animal; D006965:Hyperplasia / Q000473:pathology / Q000601:surgery; D018810:Magnetic Resonance Angiography; D008297:Male; D011138:Polytetrafluoroethylene; D013552:Swine; D017539:Tunica Intima / Q000473:pathology* / Q000601:surgery; D018616:Ultrasonography, Doppler, Duplex; D014656:Vascular Surgical Procedures / Q000379:methods*
D011138:Polytetrafluoroethylene