May 15, 2009 - Intraoperative fluorescence imaging (IFI) can evaluate graft patency during off-pump coronary artery bypass graft (CABG) surgery, making possible immediate graft revision, if needed, and potentially better clinical outcomes, according to a study in the May issue of the Journal of the American College of Cardiology: Cardiovascular Imaging. Katsuhisa Waseda, M.D., of Stanford University Medical Center in California, and colleagues performed IFI on a total of 507 grafts in 137 patients undergoing off-pump CABG. IFI analysis, intraoperative transit time flowmetry (TTFM), and postoperative X-ray angiography all were used to evaluate graft patency, and IFI and TTFM were compared. Researchers were able to visualize clearly up to the distal anastomosis in 379 grafts (75 percent). More than 80 percent of IFI images were analyzable, with anterior location producing 90 percent of analyzable images, without regard to graft type. Six grafts that had acceptable TTFM results were diagnosed with graft failure using IFI, which required immediate graft revision. Another 21 grafts that had unsatisfactory TTFM results exhibited acceptable patency with IFI, and graft revision was not performed. The authors further note that 20 of the 21 grafts demonstrated satisfactory patency in postoperative X-ray angiography. "The IFI system enables on-site assessment of graft patency, providing both morphologic and functional information in off-pump bypass patients. This unique technique may help identify procedure-related early graft failures, permitting on-site revision, and thereby contributing to improved clinical outcomes for off-pump CABG patients," the authors write.
Intraoperative Fluorescence Imaging Evaluates Graft Patency in CABG Surgery
A pig heart, shown here, is very similar in size and anatomy to a human heart. For this reason, pigs are used extensively in pre-clinical animal testing for new implantable cardiovascular devices. If pig hearts could be used for human transplantation, it would greatly alleviate shortages of donor human hearts.