Meta-analysis of organ damage after conversion from off-pump coronary artery bypass procedures

The relative efficacy of off-pump and on-pump coronary revascularization is uncertain. A complication of off-pump surgery which is rarely considered is intraoperative conversion to cardiopulmonary bypass. Consequently, meta-analysis was performed of studies comparing morbidity after converted and nonconverted off-pump coronary revascularization. There were significant increases in the likelihood of stroke, myocardial injury, bleeding, renal failure, wound infection, intraaortic balloon pump requirement, transfusion, and respiratory and gastrointestinal complications after conversion. The underlying mechanisms need to be urgently elucidated. Prevention and treatment protocols for conversion warrant serious consideration and the risk of conversion may need to be discussed when obtaining informed patient consent.