Postoperative Outcomes after Off-Pump Coronary Artery Bypass Grafting in EuroSCORE Low- and High-Risk Women

Abstract

Many previous studies have reported that women who undergo coronary artery bypass grafting have higher perioperative morbidity and mortality rates than men. The use of off-pump coronary artery bypass grafting (OPCAB) has been suggested to decrease morbidity and mortality because the deleterious effects of cardiopulmonary bypass, particularly in high-risk patients, are avoided. The reduction in unwanted postoperative complications in women undergoing OPCAB surgery has not been extensively investigated. The aim of this retrospective study was to compare perioperative rates of morbidity and mortality and follow-up events after OPCAB in female patients assessed as high- or low-risk according to the European System for Cardiac Operative Risk Evaluation (EuroSCORE). The study included 377 adult female patients who underwent elective primary isolated OPCAB. The study patients were divided into 2 groups based on the Additive EuroSCORE: low-risk patients (group I, n = 301, EuroSCORE < 6) and high-risk patients (group II, n = 76, EuroSCORE > or = 6). Patient ages were 60.1 +/- 7.77 years in group I and 69.3 +/- 5.51 years in group II (P <.001). Compared to group I patients, group II patients had significantly higher Additive EuroSCORE (P <.001), predicted mortality rate (Logistic EuroSCORE) (P <.001), and Canada angina classification (P <.001) and higher rates of preoperative myocardial infarction (P <.001), peripheral vascular disease (P <.001), carotid artery disease (P <.005), and hypertension (P <.05). Occurrence of postoperative arrhythmia and mortality were significantly higher (P <.05) in group II. The observed mortality rate in group I was 1%, which was 41% of the predicted mortality rate (Logistic EuroSCORE) of 2.42 +/- 0.76. The observed mortality rate in group II was 5.3%, which was 79% of the predicted rate (6.74 +/- 2.89), but the difference was not significant (P = .2). Intensive care unit length of stay (P <.01) and ventilation times (P <.05) were longer for group II than group I, and the incidence of conversion to cardiopulmonary bypass was 1.6% versus 5.3%, respectively, in groups I and II (P = .08). These results indicate that OPCAB surgery is safe and seems to be an effective surgical technique for lowering rates of morbidity and mortality in high- and low-risk female patients.