Risk factors of atrial fibrillation following off-pump coronary artery bypass graft surgery: predictive value of C-reactive protein and transfusion requirement.

OBJECTIVES: Considering the role of inflammatory reaction on the pathogenesis of atrial fibrillation (AF), the aim of this study is to investigate perioperative risk factors of AF, as well as to validate the predictive value of high-sensitive C-reactive protein (hsCRP), and transfusion requirement following off-pump coronary bypass surgery (OPCAB) in a prospective and observational trial.

METHODS: In this cohort, 315 consecutive patients with normal sinus rhythm (NSR) undergoing elective isolated OPCAB are prospectively studied. The patients were classified as either NSR or AF group according to their postoperative rhythm, which was continuously monitored for the first 6 postoperative days.

RESULTS: AF developed in 66 patients (19%). Univariate analysis demonstrated old age, pre-existing chronic renal failure, low left ventricle ejection fraction (LVEF <30%), highest hsCRP before the onset of AF, vasopressor and inotropic therapy, packed red blood cells (pRBCs) transfusion and amount of chest tube drainage as predictors of postoperative AF. In a stepwise multivariate analysis of these risk factors, low LVEF (odds ratio: 2.88; 95% confidence interval: 1.07-7.75; p=0.037), highest hsCRP before the onset of AF (odds ratio: 1.06; 95% confidence interval: 1.01-1.11; p=0.018), vasopressor therapy (odds ratio: 1.93; 95% confidence interval: 1.04-3.57; p=0.038) and pRBC transfusion (odds ratio: 5.32; 95% confidence interval: 2.80-10.11; p<0.001) remained as independent predictors of postoperative AF.

CONCLUSIONS: Prophylactic strategies aimed at AF reduction may also be considered especially in patients with increased transfusion requirement, which showed highest predictive value for postoperative AF.