Predictors of paroxysmal atrial fibrillation in patients undergoing aortic valve replacement

Objective: Atrial fibrillation is one of the most common complications after cardiac surgery. This study evaluates the risk factors of paroxysmal atrial fibrillation in patients who underwent aortic valve replacement. Methods: The study comprised 300 patients with aortic valve defects of either aortic stenosis (n = 150) or regurgitation (n = 150) who underwent aortic valve replacement. For each patient, 2-mode and Doppler echocardiographic examinations were performed in the preoperative period, early postoperative period, and long-term observation, and selected hemodynamic parameters were analyzed. Results: Factors significantly associated with atrial fibrillation in patients with aortic stenosis were heart failure (odds ratio = 5.5), age 70 years or more (4.5), low (3.9) and high body mass index (1.7), maximal transvalvular gradient (3.7), low left ventricular ejection fraction (5.1), end-systolic (2.9) and end-diastolic intraventricular septum thickness (1.5), and insignificant mitral regurgitation (1.9) in the preoperative period; and left ventricular ejection fraction (4.4) and end-systolic intraventricular septum thickness (1.8) in the early postoperative period. In the aortic regurgitation group, factors significantly associated with atrial fibrillation were age (1.8), left ventricular ejection fraction (3.7), left ventricular end-systolic diameter (1.7), end-diastolic intraventricular septum thickness (1.7), left atrium dimension (4.1) and insignificant mitral regurgitation (2.5) in the postoperative period; essential arterial hypertension (3.3), diabetes mellitus (2.6), and heart failure in the history (4.5) in the preoperative period; and left ventricular ejection fraction (1.9) and left atrium dimension (2.9) in the early postoperative period. Conclusion: On the basis of the separated risk factors, all patients should be preoperatively classified to applicable groups of risk of postoperative atrial fibrillation appearance, and the prophylactic treatment should be administered in the group of patients with the highest risk. It may essentially decrease the rate of complications and deaths, and, consequently, the costs of postoperative medical care.