Abstract 2541: Angiographic Predictors of 6-Month Patency of Bypass Grafts Implanted on the Right Coronary Artery: A Prospective Randomized Comparison of Gastroepiploïc Artery and Saphenous Vein Grafts
Background: Saphenous vein grafts (SVG) and pedicled gastroepiploic artery grafts (GEA) are routinely used to revascularize the right coronary artery (RCA). Little is known about the predictive value of objective preoperative angiographic parameters on the 6-month graft patency and on the interest of these parameters to select the optimal graft material in individual cases.
Methods: We prospectively enrolled 154 consecutive patients candidates to coronary revascularization. Revascularization of the RCA was randomly performed with SVG in 77 patients and with the GEA in 77 patients. Both groups were comparable with respect to all preoperative continuous and discrete variable and risk factors. All patients underwent a systematic angiographic control 6 months after surgery. Preoperative angiographic parameters included minimal lumen diameter (MLD), percent stenosis and reference diameter of the RCA measured by quantitative angiography (CAAS II system), location of the stenosis, run off of the RCA and myocardial viability. The endpoint was graft patency and flow pattern.
Results: Flow patterns were categorized as graft-dependent (n=109), balanced (n=20), native-dependent (n=11) or occluded (n=14). No significant difference in the distribution of flow patterns was observed between SVG and GEA. In multivariate analysis, only MLD and run off were significantly associated with a graft-dependent flow pattern in patients treated with a GEA. In these patients, patency was significantly improved when MLD was below a threshold value of 0.76 mm. In patients treated with a SVG, multivariate analysis failed to demonstrate any significant association between angiographic parameters and flow pattern.
Conclusion: MLD of the RCA below 0.76 mm and a large run off predict a favorable flow pattern in GEA, whereas the commonly used criteria (percent stenosis and reference vessel size) do not. In SVG, the flow pattern is not influenced by any of these quantitative angiographic parameters.