Predictors of atrial fibrillation after off-pump coronary artery bypass graft surgery

Background: Postoperative atrial fibrillation (AF) is one of the most commoncomplications after cardiothoracic surgery and is associatedwith an increased risk of stroke, and longer hospital stay.The pathophysiology of postoperative AF is uncertain, and itsprevention remains unsatisfactory. Many previous studies haveexamined the predictors of AF after on-pump coronary arterybypass graft surgery (CABG), but there are few reports afteroff-pump CABG. Methods: The aim of the present prospective observational study, in which296 consecutive patients were enrolled, was to elucidate thepredictors of AF after off-pump CABG. The association of perioperativefactors with AF was investigated using univariate analysis.Significant variables were included into a stepwise logisticregression model to ascertain their independent influence onthe occurrence of AF. Results: The incidence of AF was 32%. AF prolonged the time until patientswere fit for discharge by 3 days (P < 0.01). Stepwise multivariateanalysis identified increasing age [odds ratio (OR) 1.44 per10-yr increase; 95% confidence interval (CI) 1.06–1.95],intraoperative average core temperature (OR 1.64; 95% CI 1.05–2.56),the average cardiac index in the intensive care unit (OR 0.37;95% CI 0.19–0.71), and intraoperative fluid balance (OR0.96 per 100-ml increase; 95% CI 0.93–0.99) as independentpredictors of postoperative AF. Conclusion: Our present findings indicate that ageing, the intraoperativefluid balance, and postoperative cardiac index are associatedwith the onset of AF after off-pump CABG.