Acute atrial fibrillation (AAF) in cardiac surgery postoperative period: evaluation of pre- and perioperative factors associated with its higher incidence

Background

Some pre- and perioperative factors have been associated with a high incidence of AAF in cardiac surgery postoperative period. Advanced age, longer surgery time, mitral valve surgery and stopping β-blockade have been described.

Objective

To evaluate some pre- and perioperative factors in order to identify those patients with higher probability for postoperative AAF.

Patients and method

A total of 227 adult patients consecutively admitted in postoperative period were prospectively followed. Clinical and surgical variables were collected and then compared between patients who developed AAF in postoperative period and those who did not. Statistical techniques were Student's t test and Fischer test.

Results

The mean age in the two groups were significantly different (69.9 years in AAF patients and 62.6 years in non-AAF patients; P < 0.01). The AHA/ACC mortality and stroke indexes were higher in AAF patients (P < 0.01 and P < 0.001, respectively). Water retention on the first postoperative day was higher in AAF patients (P < 0.01). Euroscore and Cleveland scale were higher in AAF group (P < 0.001 for both indexes). Left atrial size, body mass index, AHC/ACC mediastinitis scale, Goldman index, surgery time, extracorporeal circulation time, aortic clamping time, peroperative water intake, diabetes, chronic obstructive pulmonary disease, left ventricular function, MODS and SOFA indexes were not statistically different in the two groups. AAF incidence was higher in mitral valve postoperative period when compared to post-revasculariza-tion period, but it has not met statistical significance.

Conclusion

Advanced age, AHA/ACC mortality and stroke indexes, Euroscore and Cleveland scale, and water retention on the first postoperative day were shown to be predictors for AAF in cardiac postoperative period. As few patients have undergone mitral valve surgery, it was not possible to detect statistical difference in AAF incidence between these patients and those who have undergone myocardial revascularization.