Objective: To evaluate 30-day and late results in high risk patients (European score (EuroSCORE) > or = 6) who underwent isolated myocardial revascularization with and without cardiopulmonary bypass (CPB).
Methods: From November 1994 to December 2001, 1266 patients with EuroSCORE > or = 6 underwent isolated myocardial revascularization. Among them, applying the propensity score, we were able to select 1020 patients operated on without CPB (group A, n=510) and with CPB (group B, n=510) with the same preoperative characteristics. The only differences were the higher incidence of patients with age between 61 and 65 years (9.4% in group A vs. 13.9% in group B, P=0.025) and the lower number of anastomoses/patient in group A (1.8+/-0.9 vs. 2.8+/-0.9, P<0.001). EuroSCORE were identical in both groups (7.8%).
Results: Thirty-day mortality was higher in group B (5.9 vs. 3.1%, P=0.035). Group A showed a lower incidence of cerebrovascular accidents (CVAs) (0.6 vs. 3.1%, P=0.003), whereas incidence of acute myocardial infarction (AMI) was similar (2.0% in group A vs. 2.5% in group B, P=ns). Early negative primary end-points and early major events incidences were higher in group B (8.2 vs. 3.9%, P=0.004, and 14.5 vs. 7.1%, P<0.001, respectively). Stepwise logistic regression confirmed that CPB was an independent predictor for higher early mortality (Odds ratio (OR) 2.0) and CVA, negative primary end-points and early major events incidences (OR 4.6, 2.3 and 2.4, respectively). Five-year freedom from the events explored (death due to any cause, cardiac death, AMI, AMI on a grafted area, redo/percutaneous transluminal coronary angioplasty (PTCA), redo/PTCA on a grafted area, target cardiac events (cardiac death, AMI in a grafted area and redo/PTCA in a grafted area) and any event were similar in both groups.
Conclusions: In high risk patients myocardial revascularization without CPB shows better early outcome and similar clinical late results.