[Analysis of risk factors of the paroxysmal atrial fibrillation after valve replacement in patients with aortic stenosis].

UNLABELLED: Paroxysmal atrial fibrillation (PAF) is a frequent complication (10-60% of pts) after cardiac surgery. In our study we analyze the influence of clinical, echocardiographic and 24 h ecg parameters on the risk of postoperative PAF in 266 pts with aortic stenosis (88 women and 178 men; mean age 58 +/- 10). PAF was observed in 74 (28%) patients. Statistically significant factors of risk of PAF were (univariate analysis): age-relative risk 1.08 (1.04-1.11), history of PAF--4.3 (1.4-12.5), more than 100 supraventricular ectopic beats during 24 h ecg--2.9 (1.6-5.1), presence of SVT during 24 h ecg--2.6 (1.5-4.5) and presence of SVT > 140/min--relative risk 3.5 (1.8-6.7). Left atrium diameter and coronary artery bypass grafting during valve replacement had no impact on the risk of PAF. In multivariate analysis three factors remained significant--age, history of PAF and presence of SVT > 140/min during 24 h ecg. In discriminant analysis this model of 3 factors enabled the correct risk assessment in 72% of patients.

CONCLUSIONS: 1. The factors that increase the risk of postoperative PAF in pts with aortic stenosis are: age, history of PAF and presence of SVT > 140/min during preoperative 24 h ecg. 2. Postoperative PAF is not related to left atrium diameter in this group of patients. 3. Coronary artery bypass grafting during aortic valve replacement does not increase the risk of PAF.