Related Experiment Video
Updated: Feb 19, 2026
Establishment and Evaluation of a Porcine Vein Graft Disease Model
Published on: July 25, 2022
A comparison of postoperative morphometric and hemodynamic changes between saphenous vein and left internal mammary
Tingting Fan1, Yundi Feng1, Feng Feng1
1Mechanics and Engineering Science, College of Engineering, Peking University, Beijing, China.
Insights
Saphenous vein graft (SVG) failure is higher than left internal mammary artery (LIMA) graft failure due to hemodynamic changes. This study reveals worsening graft structure and blood flow over time, contributing to disease progression.
Area of Science:
- Cardiovascular Surgery
- Biomedical Engineering
- Medical Imaging
Background:
- Saphenous vein grafts (SVGs) exhibit higher long-term failure rates compared to left internal mammary artery (LIMA) grafts.
- The hemodynamic environment significantly influences SVG performance and atherogenesis.
Purpose of the Study:
- To comprehensively analyze postoperative structure-function changes in SVG and LIMA grafts.
- To compare morphometric and hemodynamic parameters between SVG and LIMA grafts at multiple time points (1, 5, and 10 years postoperatively).
- To investigate the relationship between structural changes and hemodynamic alterations in graft failure.
Main Methods:
- Utilized CT imaging for reconstruction and computational fluid dynamics for flow simulation in patients.
- Analyzed morphometric parameters (lumen size) and hemodynamic parameters (time-averaged wall shear stress - TAWSS, TAWSS gradient - TAWSSG).
- Compared graft parameters at approximately 1, 5, and 10 years after coronary artery bypass grafting.
Main Results:
- Observed a progressive decrease in SVG lumen size and anastomosis dimensions over 10 years, unlike LIMA grafts.
- Documented a fourfold increase in the surface area ratio (SAR) of low TAWSS in SVG at 10 years compared to 1 year.
- Found a significantly higher SAR of high TAWSS gradient at the distal SVG anastomosis compared to LIMA at 1 year.
Conclusions:
- Morphometric and hemodynamic changes in SVGs correlate strongly, indicating progressive deterioration and diffuse disease development.
- Hemodynamic factors, particularly altered wall shear stress, play a crucial role in SVG failure and atherogenesis.
- Long-term monitoring of both structural and hemodynamic parameters is essential for understanding and potentially mitigating SVG disease.
Abstract:
There is higher long-term failure of the saphenous vein graft (SVG) compared with the left internal mammary artery (LIMA) graft, which is affected by the hemodynamic environment. A comprehensive analysis of postoperative structure-function changes is important to study the atherogenesis in the SVG A comparison of morphometric and hemodynamic parameters was carried out between LIMA grafts and SVGs and between different time points postoperatively. Various parameters were obtained from the image reconstruction and flow simulation in patients, who underwent CT exams for ~1 year, 5 and 10 years after revascularization. Morphometric data showed a decrease in lumen size in the entire SVG and anastomosis of different patients in a sequence of ~1 year, 5 and 10 years postoperatively despite negligible changes of LIMA size. Computational results indicated the fourfold increased surface area ratio (SAR) of low time-averaged wall shear stress (TAWSS) in the SVG and anastomosis at postoperative 10 years than that at postoperative ~1 year. The SAR of high TAWSS gradient (TAWSSG) at the distal anastomosis between SVG and coronary arteries was significantly higher (14 ± 9% vs. 6 ± 8%) than that in the LIMA group at postoperative ~1 year. There were strong correlations between morphometric and hemodynamic parameters in the SVG and distal anastomosis at various time points postoperatively, which showed deterioration relevant to persistent diffuse diseases at postoperative ~10 years.
