Comparison of Radial Artery and Saphenous Vein Graft Stenosis More Than 5 Years After Coronary Artery Bypass Grafting.

BACKGROUND:Graft stenosis may be associated with future graft failure. The purpose of this investigation was to compare graft stenosis between radial artery (RA) grafts and saphenous vein grafts (SVGs) at least 5 years postoperatively using the multicenter Radial Artery Patency Study (RAPS) data. METHODS:Two hundred thirty-four patients underwent late invasive angiography after coronary artery bypass operations. The study population consists of 163 patients with thrombolysis in myocardial infarction (TIMI) 3 flow of both the RA graft and study SVGs. Angiograms were reviewed centrally and in a blinded fashion. Graft stenosis was recorded for the proximal anastomosis, graft body, and distal anastomosis; significant stenosis was defined as greater than or equal to 50%. Major adverse cardiac events (MACE) were reported in patients with and those without significant graft stenosis. RESULTS:There was no difference in significant graft stenosis of the patent RA grafts and SVGs (14 of 163 [8.6%] versus 19 of 163 [11.7%]) or in the proximal anastomosis (5 of 163 [3.1%] versus 5 of 163 [3.1%]), graft body (6 of 163 [3.7%] versus 13 of 163 [8.0%]), or distal anastomosis (4 of 163 [2.5%] versus 5 of 163 [3.1%]) considered separately. However, the overall burden of graft body disease was higher in SVGs (p = 0.03). MACE was higher in patients with significant graft stenosis than in patients without stenosis (10 of 28 [35.7%] versus 7 of 135 [5.2%]; p < 0.0001). CONCLUSIONS:There was no significant difference in the rates of significant stenosis of patent RA grafts and SVGs more than 5 years postoperatively. However, the burden of graft body stenosis was less in RA grafts compared with SVGs, suggesting that the RA grafts will continue to outperform the SVGs late after operation.