Related Experiment Videos
Mechanical and histologic changes in canine vein grafts
P B Dobrin1, F N Littooy, J Golan
1Department of Surgery, Hines VA Hospital, Illinois 60141.
The Journal of Surgical Research
|March 1, 1988
Summary
Vein grafts used for arterial bypass dilated significantly within 4 weeks. Intimal hyperplasia and medial thickening appear to be separate responses to different stimuli in vascular grafts.
Area of Science:
- Vascular Surgery
- Biomedical Engineering
- Histopathology
Background:
- Femoral vein grafts are utilized in bypass surgery to restore blood flow to ligated arteries.
- Understanding the mechanical and histological changes in vein grafts is crucial for improving surgical outcomes.
- Vein graft compliance and structural integrity influence graft patency and long-term success.
Purpose of the Study:
- To investigate the mechanical properties and histological changes of canine femoral vein grafts after arterial bypass implantation.
- To compare the effects of different anastomosis techniques (end-to-side vs. end-to-end) on vein graft remodeling.
- To evaluate the impact of aspirin and dipyridamole treatment on intimal hyperplasia in vein grafts.
Main Methods:
- Mechanical testing of native and implanted femoral vein grafts to assess compliance and distensibility.
- Histological examination of vein grafts to quantify intimal hyperplasia and medial thickening.
- Comparison of grafts implanted with end-to-side versus end-to-end anastomoses.
- Assessment of the effects of aspirin and dipyridamole on histological changes.
Main Results:
- Vein grafts exhibited rapid dilation, reaching 90% of maximum dilation by 4 weeks post-implantation.
- Both native veins and grafts showed high compliance up to 35-50 mm Hg, becoming nondistensible at higher pressures.
- End-to-side anastomoses resulted in greater intimal hyperplasia compared to end-to-end anastomoses (P < 0.05).
- Aspirin and dipyridamole treatment significantly reduced intimal hyperplasia in end-to-side grafts (P < 0.05).
- Medial thickening was increased in all grafts compared to native veins (P < 0.05) but was not significantly different between anastomosis types or with drug treatment.
Conclusions:
- Intimal hyperplasia and medial thickening represent distinct biological responses to different stimuli in vascular grafts.
- The compliance of the anastomotic region is influenced by the mechanical properties of the adjacent artery.
- Pharmacological intervention with aspirin and dipyridamole can mitigate intimal hyperplasia, a key factor in graft failure.