In contrast, patients without ischemia in the LAD artery distribution do not derive a survival benefit from repeat CABG. In an observational study from the Cleveland Clinic, the survival rate of 4640 patients with patent LIMA grafts to the LAD artery and ischemia in the distribution of the right and/or left circumflex arteries who were treated with repeat CABG, PCI, or medical therapy was examined.380 No improvement in survival was observed in either revascularization group com- pared with those treated medically. 6.8.2. Operative Risk Because of the technical difficulty of repeat CABG and the high risk profiles of these patients, reoperative CABG is associated with higher rates of morbidity and mortality than is primary CABG.945,1229 1235 With advances in surgical tech- niques, some groups have reported a decline in mortality rate for patients undergoing repeat CABG.1233,1236 An observa- tional study suggested that the higher operative risk with reoperation is related to the higher patient risk profiles and not to the technical challenges of the operation itself, thereby suggesting that improvements in surgical techniques have neutralized the risk associated with the complexity of repeat CABG,1233 but others continue to suggest that technical issues are still important in causing the higher mortality rate in these individuals. 6.8.3. Long-Term Outcomes The survival rate after repeat CABG is lower than that after primary CABG. A multicenter study from Australia reported 1, 3, 5, and 6 year survival rates in reoperative CABG patients of results that were significantly lower than those observed after primary CABG. However, after adjusting for differences in risk profiles between primary and reoperative CABG patients, no difference in long-term survival rate was apparent. 