Does off-pump coronary artery bypass surgery reduce mortality in high riskpatients?

Background: The aim of this retrospective study was to compare outcome in t wo groups of patients who were classified according to their risk groups an d underwent coronary revascularization with or without cardiopulmonary bypa ss. Material and Methods: Between January 1996 and July 2000, 480 cases that un derwent coronary artery bypass surgery (CABG) were included in a retrospect ive nonrandomized manner for study. Group I included 210 patients who were revascularized using off-pump techniques. Octopus 2 and 3 (Medtronic, Inc., Minneapolis, MN) were used for tissue stabilization. Group 2 included 270 cases who underwent CABG using CPB. Emergency cases, combined operations, reoperations, and patients in cardiog enic shock were excluded. Demographic variables were comparable between two the groups. Using the Allegheny Clinic Risk Scoring Scale [Magovern 1996], patients in both groups were scored as low, moderate, and high risk. In Gr oup 1, 37% of patients consisted of high risk patients while Group 2 had 14 % (p < 0.05), Student's t-test and chi-square test were used for statistical analysis and alfa < 0.05 was considered significant. Results: Mortality was 1.4% in Group 1 and 1.5% in Group 2 (p = ns). Mean a nastomosis per patient was 2.6 +/- 0.6 in Group 1 and 3.2 +/- 0.5 in Group 2 (p < 0.05). Patients in Group I needed less blood transfusions and less i notropic support postoperatively (p < 0.05). There were also fewer minor ne urological events (p < 0.05) and pulmonary complications (Type 2) in Group 1. Atrial fibrillation rate, infection, and major neurological deficit (Typ e 1) were similar in both groups. Mortality was less among Group 1 high risk patients (3.9%) in comparison to Group 2 high risk patients (7.9%), but this did not reach statistical sign ificance. Conclusions: In low or moderate risk patients, CABG can be performed safely with or without CPB. In high risk patients with several comorbidities, off -pump CABG seems to be a safe and efficient method that can improve outcome .