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Updated: Jun 18, 2026
A Novel Approach to Monitoring Graft Neovascularization in the Human Gingiva
Published on: January 12, 2019
Intraoperative grafts assessment
Marzia Leacche1, Jorge M Balaguer, John G Byrne
1Vanderbilt Heart and Vascular Institute, Nashville, Tennessee, USA.
Insights
Coronary artery bypass grafting outcomes depend on graft patency. Intraoperative imaging like transit time flow measurement and intraoperative fluorescence imaging have limitations, but hybrid suites with angiography can improve graft assessment and revision.
Area of Science:
- Cardiovascular Surgery
- Medical Imaging
- Interventional Cardiology
Background:
- Graft patency is critical for successful coronary artery bypass grafting (CABG) outcomes.
- Current CABG standards lack routine intraoperative imaging for graft assessment.
- Transit time flow measurement (TTFM) and intraoperative fluorescence imaging (IFI) are used but have limitations in detecting subtle graft abnormalities.
Purpose of the Study:
- To evaluate the utility of intraoperative imaging techniques for assessing coronary artery bypass graft integrity.
- To highlight the limitations of current methods (TTFM and IFI) in identifying suboptimal grafts.
- To introduce the potential of hybrid suites for routine completion angiography in CABG.
Main Methods:
- Review of existing intraoperative graft assessment techniques: TTFM and IFI.
- Discussion of the capabilities and limitations of TTFM (quantitative flow) and IFI (semiquantitative imaging).
- Introduction of hybrid suites enabling intraoperative angiography post-CABG.
Main Results:
- TTFM and IFI can identify completely patent or occluded grafts but struggle with subtle abnormalities.
- Suboptimal grafts identified by these methods are associated with poor long-term patency.
- Intraoperative angiography in hybrid suites can detect abnormal grafts missed by TTFM and IFI.
Conclusions:
- Neither TTFM nor IFI are sufficiently sensitive or specific for detecting all functionally significant graft abnormalities.
- Hybrid suites facilitating routine completion angiography offer a solution for identifying and revising suboptimal grafts before OR closure.
- This approach has the potential to improve long-term graft patency and patient outcomes after CABG.
Abstract:
Graft patency strongly influences early and late outcomes after coronary artery bypass grafting (CABG) surgery. The current standard of care in CABG surgery does not require intraoperative imaging. Because coronary angiography is rarely available in the operating room (OR), other techniques have been developed to assess graft integrity intraoperatively. The 2 most commonly used are the transit time flow measurement (TTFM) and the intraoperative fluorescence imaging (IFI). The TTFM is a quantitative volume flow technique, whereas the IFI is based on the fluorescent properties of indocyanine green. TTFM cannot define the degree of graft stenosis nor discriminate between the influence of the graft conduit and the coronary arteriolar bed on the mean graft flow. IFI provides a "semiquantitative" assessment of the graft patency with images that provide some details about the quality of coronary anastomoses. Both methods are valuable in identifying only at the extremes, that is, either patent or occluded grafts, and can confirm very good grafts; however, neither method is sensitive or specific enough in identifying more subtle abnormalities. These abnormal grafts most likely have poor long-term patency and are predestined to fail. The hybrid suite has the capability of serving both as a complete surgical OR and as a catheterization laboratory. It allows for routine completion angiogram following CABG surgery and identifies abnormal grafts, providing the opportunity to revise them with percutaneous coronary intervention or surgery before leaving the OR.
