Off-pump coronary bypass surgery for high-risk patients: only in expert centers?

Off-pump coronary artery bypass (OPCAB) grafting has been increasingly adopted in an effort to prevent deleterious effects of cardiopulmonary bypass, including the associated inflammatory response, global myocardial ischemia and the risks of aortic manipulation. In many studies, the greatest benefit of OPCAB has been in high-risk patients. This review will summarize the recent literature examining outcomes of OPCAB versus on-pump coronary artery bypass in high-risk subgroups, and will examine the safety of routine application of OPCAB in these patients.

Prospective randomized trials have shown that in comparison to on-pump coronary artery bypass, OPCAB reduces perioperative morbidity, but have failed to show a mortality benefit, owing to small sample sizes. However, numerous large retrospective series and meta-analyses have demonstrated a reduction in risk-adjusted mortality and morbidity with respect to the following outcomes: stroke, pulmonary function, renal function, atrial fibrillation, need for early reoperation, blood transfusion requirements, length of ICU and hospital stay, and hospital costs. An even greater benefit has been seen in the following high-risk patients: those with acute myocardial infarction, left ventricular dysfunction, previous history of stroke, renal insufficiency, women, elderly patients, and those undergoing reoperations.

Risk-adjusted outcomes are superior after OPCAB versus on-pump coronary artery bypass for mortality and numerous morbidity endpoints. This benefit is most easily demonstrated in high-risk patient populations.