Remodeling of the radial artery anastomosed to the internal thoracic artery as a composite straight graft.
OBJECTIVE
The internal thoracic artery remodels its diameter in response to flow requirements. The purpose of this study was to elucidate the remodeling of the radial artery as a composite straight graft with the internal thoracic artery.


METHODS
We studied 39 patients who underwent coronary artery bypass grafting. Nineteen patients received composite straight radial and internal thoracic artery grafts, and 20 received saphenous vein grafts as aortocoronary conduits. All the grafts were sequentially anastomosed to native coronary arteries. We measured the diameters of the internal thoracic and radial arteries before surgical intervention and 3 weeks and 1 year after surgical intervention and the differences in diameter of the radial artery and saphenous vein grafts before the first and second anastomoses with native coronary arteries.


RESULTS
The radial arteries were significantly larger in diameter than those of the internal thoracic arteries before surgical intervention (3.54 +/- 0.46 vs 2.31 +/- 0.40 mm, P < .0001), but there was no significant difference 3 weeks after surgical intervention (2.19 +/- 0.49 vs 2.15 +/- 0.45 mm). The mean diameters of the radial and internal thoracic arteries remained almost the same 1 year after surgical intervention (2.22 +/- 0.49 and 2.32 +/- 0.79 mm). The diameters of the radial artery grafts were significantly reduced after the first anastomosis (P < .01), but those of the saphenous vein grafts were unchanged.


CONCLUSIONS
These results suggest that a composite straight radial and internal thoracic artery graft without a change in shear stress behaves like an extended arterial graft, with remodeling and vasoreactive capacity.
Fukui
Shinya
S
Division of Cardiovascular Surgery, Sakurabashi-Watanabe Hospital, Osaka, Japan. fukui0104@yahoo.co.jp
Fukuda
Hirotsugu
H
Toda
Koichi
K
Yoshitatsu
Masao
M
Funatsu
Toshihiro
T
Masai
Takefumi
T
Miyamoto
Yuji
Y
D000368:Aged; D000714:Anastomosis, Surgical; D001026:Coronary Artery Bypass / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008323:Mammary Arteries / Q000502:physiology / Q000601:surgery*; D008875:Middle Aged; D017534:Radial Artery / Q000502:physiology* / Q000601:surgery* / Q000637:transplantation; D012501:Saphenous Vein / Q000502:physiology* / Q000637:transplantation