Predictors of Postoperative Atrial Fibrillation after Heart Valve Surgery

Background- Atrial fibrillation (AF) is the most common complication after cardiac surgery and a major cause of morbidity and increased cost of care. Suitable treatment and prevention of postoperative AF are important for patients’ improved health and rehabilitation. This study evaluates the risk factors of paroxysmal AF in patients who underwent valvular heart surgery. Method- Between April and October 2006, 392 patients who underwent heart valve surgery at our center were included in this prospective study. All relevant clinical, echocardiographic, and laboratory data were gathered in all the patients. Results- Postoperative AF occurred in 52 (13.3%) patients. In the univariate analysis, the presence of aortic valve disease, mitral valve disease, dyslipidemia, preoperative digoxin consumption, postoperative adrenergic use, intra-aortic balloon pump (IABP) insertion in post-surgery intensive care unit, and large left atrium were significantly associated with the occurrence of postoperative AF (all P<0.05). However, in the stepwise logistic regression model, dyslipidemia (OR: 2.39, 95% CI: 1.12-5.09, P=0.020), left atrium dimension (OR: 0.12, 95% CI: 0.76-0.28, P<0.001), IABP (OR: 7.10, 95% CI: 1.98-25.47, P=0.001), preoperative digoxin use (OR: 2.55, 95% CI: 1.38-4.71, P=0.002), postoperative adrenergic use (OR:3.70, 95% CI: 1.77-7.73, P<0.001), aortic valve replacement (OR:0.38, 95% CI: 0.20-0.69, P=0.0001), and mitral valve replacement (OR:3.53, 95% CI: 1.75-7.10, P<0.001) remained independently predictive of postoperative AF. Conclusions- The result of this study showed that dyslipidemia, left atrium dimension, mitral valve replacement, aortic valve replacement, IABP, and adrenergic use in ICU and digoxin use preoperatively were the independent predictors of AF after valvular surgery. Therefore, clinical data and echocardiography may be useful in preoperative risk stratification of high-risk patients for the occurrence of postoperative AF(Iranian Heart Journal 2008; 9 (2):10-17).