Risk factors for low cardiac output syndrome after coronary artery bypass grafting surgery.

OBJECTIVES Low cardiac output syndrome (LCOS) is a serious complication after cardiac surgery and is associated with significant morbidity and mortality. The aim of this study is to identify risk factors for LCOS in patients undergoing coronary artery bypass grafting (CABG) in the Division of Cardiovascular Surgery of Pronto Socorro Cardiológico de Pernambuco - PROCAPE (Recife, PE, Brazil). METHODS A historical prospective study comprising 605 consecutive patients operated between May 2007 and December 2010. We evaluated 12 preoperative and 7 intraoperative variables. We applied univariate and multivariate logistic regression analysis. RESULTS The incidence of LCOS was 14.7% (n = 89), with a lethality rate of 52.8% (n = 47). In multivariate analysis by logistic regression, four variables remained as independent risk factors: age > 60 years (OR 2.00, 95% CI 1.20 to 6.14, P = 0.009), on-pump CABG (OR 2.16, 95% CI 1.40 to 7.08, P = 0.006), emergency surgery (OR 4.71, 95% CI 1.34 to 26.55, P = 0.028), incomplete revascularization (OR 2.62, 95% CI 1.32 to 5.86, P = 0.003), and ejection fraction <50%. CONCLUSIONS This study identified the following independent risk factors for LCOS after CABG: age> 60 years of off-pump CABG, emergency surgery, incomplete CABG and ejection fraction <50%.