Coronary angiography still presents the standard for evaluation of graft patency, but is related to certain risks. Its intraoperative use is still very demanding. We present a convenient, non-invasive, intraoperative direct method of fluorescence laser angiography (DLA) for the quality control of coronary anastomoses with only minimal technical setup.
The measurement is based on the fluorescence of the near-infrared absorbing fluorescent agent ICG-PULSION® (indocyanine green). ICG-derived fluorescence is detected and recorded by a digital video camera. The video can be visually evaluated or a special software can be used to calculate a flow-dependent perfusion index for the tissue. Images were generated after injection of ICG, either directly into the grafts, via the antegrade cardioplegia cannula or via the cardiopulmonary bypass circuit.
An initial series of 11 patients suffering from CAD was operated upon on-pump in order to evaluate the efficacy of this digital method. The IMA was used in all patients. Additional flow-measurement was used in all patients. In three cases angiography was performed. 37 anastomoses (graft per patient ratio was 3.4) were performed. Graft patency, run-off were evaluated in 11 IMAs and 26 venous grafts. There were no ICG- or imaging device-related complications.CONCLUSIONS: This method is convenient, safe, provides good-quality images of coronary anatomy and grafts. It holds promises as an intraoperative graft validation tool for CABG. Our preliminary results are positive, represent first steps towards an intraoperative quality assessment of bypass grafts by DLA and aim at establishing a safety standard for OPCAB surgery in addition to flow-measurement.
Fluorescence laser angiography may become a valuable tool for intraoperative access to graft patency.
U. Kappert, None.