Instead, use of the on-pump technique was associated with better 1-year composite out- comes and 1-year graft patency rates, with no difference in neuropsychological outcomes or resource utilization. Although numerous investigators have used single- center registries, the STS database, and meta-analyses in an attempt to identify patient subgroups in whom off-pump CABG is the preferred procedure, even these analyses have reached inconsistent conclusions about off-pump CABG s ability to reduce morbidity and mortality rates.69,72 83 A retrospective cohort study of 14 766 consecutive patients undergoing isolated CABG identified a mortality benefit (OR: 0.45) for off-pump CABG in patients with a pre- dicted risk of mortality 2.5%,82 but a subsequent ran- domized comparison of off-pump CABG to traditional on-pump CABG in 341 high-risk patients (a Euroscore 5) showed no difference in the composite endpoint of all-cause death, acute MI, stroke, or a required reinterven- tion procedure.78 An analysis of data from the New York State Cardiac Surgery Reporting system did not demon- strate a reduction in mortality rate with off-pump CABG in any patient subgroup, including the elderly (age 80 years) or those with cerebrovascular disease, azotemia, or an extensively calcified ascending aorta.69 Despite these results, off-pump CABG is the preferred approach by some surgeons who have extensive experience with it and therefore are comfortable with its technical nuances. Recently, published data suggested that the avoidance of aortic manipulation is the most important factor in reducing the risk of neurological complica- tions.84,85 Patients with extensive disease of the ascending aorta pose a special challenge for on-pump CABG; for these patients, cannulation or cross-clamping of the aorta may create an unacceptably high risk of stroke. In such individuals, off-pump CABG in conjunction with avoid- ance of manipulation of the ascending aorta (including placement of proximal anastomoses) may be beneficial. 