Does skeletonization compromise the integrity of internal thoracic artery grafts?
BACKGROUND
There are few reports that demonstrate the chronologic changes in the functional integrity of the internal thoracic artery (ITA) wall after skeletonization. We investigated the impact of skeletonization on ITA wall integrity by immunohistochemical analyses in acute and chronic phases.


METHODS
Nine mongrel dogs underwent bilateral ITA dissection with one skeletonized vessel and the other pedicled. The following studies were performed 1 week (acute phase, n = 3) and 12 weeks (chronic phase, n = 6) after ITA harvesting. All specimens of the ITAs were stained by antibodies against von Willebrand Factor (VWF), endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS), and proliferating cell nuclear antigen (PCNA). After observation with confocal laser scanning microscopy, quantitative analyses of the staining signal for VWF and eNOS expressed on endothelial cells were performed.


RESULTS
There were significantly more microvessels positive for VWF in the adventitia of skeletonized ITAs than in the adventitia of pedicled ITAs but the expression of PCNA in both groups was minimal, as in normal vessels. iNOS was not detected in any specimen. The intensity of VWF and eNOS expressed by endothelial cells had no significant differences between groups at either phase.


CONCLUSIONS
The functional integrity of skeletonized ITA was similar to that of pedicled ITA in both acute and chronic phases. Although skeletonization induced neovascularization in the adventitia it did not induce proliferation of smooth muscle cells in the media, which is supposed to be a feature of vascular remodeling.
Ueda
Takashi
T
Department of Surgery III, Nara Medical University, Kashihara, Nara, Japan. u-taka@naramed-u.ac.jp
Taniguchi
Shigeki
S
Kawata
Tetsuji
T
Mizuguchi
Kazumi
K
Nakajima
Mitsuru
M
Yoshioka
Akira
A
D000818:Animals; D001026:Coronary Artery Bypass; D004285:Dogs; D004730:Endothelium, Vascular / Q000737:chemistry; D007150:Immunohistochemistry; D008323:Mammary Arteries / Q000737:chemistry / Q000473:pathology / Q000637:transplantation*; D018613:Microscopy, Confocal; D009131:Muscle, Smooth, Vascular / Q000098:blood supply / Q000473:pathology; D009389:Neovascularization, Pathologic; D019001:Nitric Oxide Synthase / Q000032:analysis; D052250:Nitric Oxide Synthase Type III; D018809:Proliferating Cell Nuclear Antigen / Q000032:analysis; D020858:Tissue and Organ Harvesting / Q000009:adverse effects / Q000379:methods*; D014841:von Willebrand Factor / Q000032:analysis
D018809:Proliferating Cell Nuclear Antigen; D014841:von Willebrand Factor; D019001:Nitric Oxide Synthase; D052250:Nitric Oxide Synthase Type III