Abstract: Objectives To investigate the angiographic characteristics and risk factors that affect graft patency underwent coronary artery bypass graft（CABG）.Methods Investigate from August 2005to May 2006,430 ptatients after CABG underwent coronary arteriograph (CAG) in our hospital due to recurrence of angina.There are 324 males and 106 females. Result The average age is (63.6±8.93) years. The average duration from CABG to CAG was (46.9±31.8) months.There are 1133 grafts , including 260 LIMA grafts,861 SVG 19 RA grafts and 1RIMA graft. Graft failure was found in 21.5%(56/261) of the IMA,32.4% (279/861)of the SVG,81.8%（8/11）of RA grafts. The patency rate of LIMA was higher the SVG(P<0.05) .There are different in patency rate of graft that to different target vessel. The rate of re-percutaneous intervention of off-pump was higher on-pump(P＜0.05).In LIMA group and SVG group, the patency rate of grafts of which the diameter of the target vessel is more than and equal to2.0mm higher than that of target vesel 2.0mm(P＜0.05). Multifactorial logistic regression analysis showed the LP(a),VLDL,diabetes were risk factors of the failure of SVG, HDL was protect factor. Most patients of SVG failure accepted drug treatment. There are no significant different between percutaneous intervention of SVG and self-vession(P>0.05). Conclusion Many factors affect the patency of grafts, select reasonable strategy of surgery and drug treatment was contribute to reduce the failure rate of grafts.

Key words: coronary artery bypass graft, coronary angiography, risk factors