Early adaptation of human lower extremity vein grafts: wall stiffness changes accompany geometric remodeling.
OBJECTIVE
To quantitatively describe the temporal changes in elastic properties and wall dimensions in lower-extremity vein grafts after implantation.


METHODS
This is a prospective study of patients (N = 38) undergoing lower extremity bypass grafts (N = 41) with autologous veins. Pulse wave velocity (PWV), luminal diameter, and wall thickness measurements were obtained by duplex ultrasound scan intraoperatively and at 1, 3, and 6 months postoperatively for assessment of graft dimensions and wall stiffness.


RESULTS
Lower extremity vein grafts showed an increase in PWV (from 16 +/- 1 to 21 +/- 3 cm/s; mean +/- SEM; P =.08), reflecting an increase in wall stiffness (from 1.2 +/- 0.2 to 2.5 +/- 0.7 x 10(6) dynes/cm; P =.02) and wall thickness (from 0.47 +/- 0.03 to 0.61 +/- 0.004 mm; P =.04) over the first 6 months after implantation. Changes in lumen diameter were positively correlated with changes in external graft diameter (P <.01) and negatively correlated with initial lumen diameter (P <.01) but not with changes in the wall thickness.


CONCLUSIONS
These results suggest complex remodeling of vein grafts during the first several months after implantation, with increased wall thickness occurring independent of variable changes in lumen diameter. Simultaneously, a marked increase in wall stiffness over this interval suggests a likely role for collagen deposition.
Division of Vascular Surgery, Bringham and Women's Hospital, Harvard Medical School, Department of Health Care Policy, Boston, MA 02115, USA.
Jeffrey G
JG
Jacot
Ibrahim
I
Abdullah
Michael
M
Belkin
Marie
M
Gerhard-Herman
Peter
P
Gaccione
Joseph F
JF
Polak
Magruder C
MC
Donaldson
Anthony D
AD
Whittemore
Michael S
MS
Conte
D000368:Aged; D000369:Aged, 80 and over; D001157:Arterial Occlusive Diseases / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery; D019917:Blood Vessel Prosthesis Implantation; D002320:Cardiovascular Physiological Phenomena; D004548:Elasticity; D005260:Female; D006801:Humans; D035002:Lower Extremity / Q000098:blood supply* / Q000000981:diagnostic imaging / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009131:Muscle, Smooth, Vascular / Q000473:pathology*; D011446:Prospective Studies; D014182:Transplantation, Autologous; D018616:Ultrasonography, Doppler, Duplex / Q000379:methods; D014680:Veins / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery / Q000637:transplantation*