Off or on bypass: What is the safety threshold?

Background. To identify the technical profile of the patients operated on w ithout cardiopulmonary bypass (CPB) and the benefit of the procedure. Methods. From May 21, 1997, to December 31, 1998,785 patients had coronary artery bypass grafting through a median sternotomy (group A: 472 without CP B; group B: 290 with CPB; group C: 23 converted). Technical aspects, mortal ity rate, cerebrovascular accident (CVA) incidence (crude and risk-adjusted ), and incidence of major complications were recorded. Results. Patients without CPB had mainly one to three grafts and one- or tw o-vessel disease. Multiple arterial grafting was not a limit, whereas seque ntial grafting was. Group A had fewer complications rates, shorter intensiv e care unit and postoperative in hospital stays, and lower transfusion rate s. Mortality rates and CVA incidence (crude and risk-adjusted) were similar in both groups and in each subgroup considered. In group A, a lower compli cations rate was present in some patients (aged greater than 70 years, fema le, with unstable angina). Group C showed higher mortality and complication s rates. Failure of revascularization showed no difference between groups. Conclusions. Primary endpoints are not affected by the surgical strategy, w hereas some of the secondary end-points are. However, patients in group A e xperienced fewer complications. Both techniques can give satisfying results and must be applied according to the surgeon's preference. (C) 1999 by The Society of Thoracic Surgeons.