The Patency Rate Of Radial Artery Grafts For Coronary Artery Bypass Grafting Surgery And The Predictive Factor Analysis

ObjectiveAt present, coronary artery bypass grafting(CABG) is the most effective therapeutic method for multi-vessel obstructive coronary artery diseases. Total arterial revascularization is the development tendency for CABG in the future. Radial artery(RA) is one of the commonly used arterial conduits. We performed a retrospective study to evaluate the postoperative patency rate of RA grafts as well as other kinds of grafts in CABG, and analyzed the predictive factors for RA grafts postoperative patency. MethodsFrom May 2009 to January 2014, patients who underwent isolated CABG and postoperative one-year coronary artery computed tomography angiography(CTA) were included in our study. There were 1173 patients,and a total of 3791 grafts were evaluated(counted by numbers of distal anastomoses), including 850 left internal mammary artery(LIMA) grafts, 2823 great saphenous vein(SVG) grafts, 112 RA grafts and 6 right internal mammary artery(RIMA) grafts. Grafts were defined as “lesioned” if they had a ≥70% stenosis, or were occluded, otherwise they were regarded as “patent”. Of the 1173 patients, 65 patients used RA grafts, which were defined as the “RA group”. According to “lesioned” or “patent” of RA grafts, the 65 patients of RA group were divided into “normal group(n=52)” and “abnormal group(n=13)”, while their 112 RA grafts(counted by numbers of distal anastomoses) were divided into “patent group(n=96)” and “lesioned group(n=16)”. According to the components of bypass grafts, the 65 patients of RA group were divided into four subgroups: the “LIMA graft+RA graft” subgroup(n=41), the “LIMA graft+RA graft+SVG graft” subgroup(n=21), the “RA graft+SVG graft” subgroup(n=1) and the “RA graft” subgroup(n=2). Preoperative, intraoperative and postoperative data were collected, then univariate analyses and logistic regress analyses were performed to explore the predictive factors for RA grafts postoperative patency. ResultsAccording to the postoperative one-year coronary artery CTA results, the total patency rate of RA grafts was 85.7%(96/112), the total occlusion rate of RA grafts was 7.1%(8/112), the functional occlusion rate of RA grafts was 5.4%(6/112), the severe stenosis(stenosis ≥70%) rate of RA grafts was 1.8%(2/112), and the postoperative mid-to-long term(3~4 years) “re-open” rate of RA grafts was 50%(2/4). The postoperative one-year patency rate of LIMA grafts(95.6%) was better than that of RA grafts(P<0.01). No significant difference was found between the postoperative one-year patency rates of RA grafts and SVG grafts(89.5%). In the “LIMA graft+RA graft” subgroup, no significant difference(P=0.073) was found between the patency rates of LIMA grafts(97.6%) and RA grafts(84.9%). In the “LIMA graft+RA graft+SVG graft” subgroup, no significant difference was found among the patency rates of LIMA grafts(90.5%), RA grafts(85.3%) and SVG grafts(89.7%) either. Univariate analyses showed that preoperative left ventricular ejection fraction(P=0.025), the combination application of anti-spastic medications after CABG(P=0.013),native stenosis of target vessel(P=0.008) and target vessel territory(P=0.020) were potential predictive factors for RA grafts postoperative patency. Logistic regression analyses showed that non-adherence to the combination application of anti-spastic medications after CABG [OR=6.825, 95%CI(1.857, 25.083), P=0.004] was an independent risk factor for RA grafts postoperative patency, while both native stenosis of target vessel ≥80% [OR=0.212, 95%CI(0.049, 0.912), P=0.037] and target vessel in LAD territory [OR=0.104, 95%CI(0.012,0.921), P=0.042] were independent protective factors for RA grafts postoperative patency. ConclusionsThe postoperative short-term patency rate of RA grafts was satisfactory. Non-adherence to the combination application of anti-spastic medications after CABG was an independent risk factor for RA grafts postoperative patency, while native stenosis of target vessel ≥80% and target vessel in LAD territory were independent protective factors for RA grafts postoperative patency. The “re-open phenomenon” and the postoperative long-term patency rate of RA grafts need further observation.