The significance of preoperative atrial fibrillation in patients undergoing cardiac surgery: preoperative atrial fibrillation--still underestimated opponent.

Atrial fibrillation (AF) has been described as an 'epidemic' due to its increasing prevalence in the ageing population. The prevalence of AF in the UK has risen from 0.78% in 1994 to 1.42% in 2006. The pathogenesis of AF seems to be multifactorial, and includes electrical and structural remodelling, and inflammation. As a result of recent developments in invasive cardiology together with improved pharmacological treatments, cardiac surgeons are increasingly operating on elderly patients with very advanced heart disease and other co-existent diseases. Therefore, AF is often present before cardiac surgery, increasing the risk of surgery and the occurrence of postoperative complications. According to available data, preoperative AF (pre-AF) should be considered as a high-risk marker of postoperative complications, which also significantly reduces long-term patient survival. However, although some multivariate models have concluded that pre-AF seems to be an independent predictor of outcome, this does not prove a cause-effect relationship. Therefore, such a link would need to be proven in prospective randomized studies, yet to be undertaken.