Determinants of postoperative atrial fibrillation and associated resource utilization in cardiac surgery.

INTRODUCTION AND OBJECTIVES

Atrial arrhythmias occur after cardiac surgery in 10-65% of patients. The most common postoperative arrhythmia is atrial fibrillation (AF).

METHODS

The Tehran Heart Center Cardiovascular Research database (of 15 580 patients) was used to identify all patients who developed any form of AF as a postoperative complication following their first cardiac surgery (e.g. for coronary artery bypass grafting [CABG], valve surgery or both), with and without cardiopulmonary bypass, between June 2002 and March 2008.

RESULTS

Of the 15 580 patients who underwent a first cardiac surgery, 11 435 (73.4%) were male and their mean age was 58.16+/-10.11 years. New-onset AF developed postoperatively in 1129 (7.2%). New-onset AF occurred most frequently in patients who were aged > or =60 years and who had no history of beta-blocker use. In addition, patients were more likely to develop new-onset AF if they had valve surgery alone (16.5%) or CABG plus valve surgery combined (9.6%), needed intra-aortic balloon counterpulsation (IABC), or had a long cardiopulmonary bypass time. Multivariate analysis identified the following predictors of postoperative AF: older age, history of renal failure, congestive heart disease, operation type, longer perfusion time, and use of IABC. The incidence of early readmission (4.4%) was significantly higher in patients with postoperative AF, as was the duration of hospitalization, both overall and postoperatively. The short-term postoperative mortality rate was 3.8%.

CONCLUSIONS

Atrial fibrillation frequently develops after cardiac surgery and is associated not only with increased morbidity and mortality, but also with increased use of health-care resources.