Predictors of postoperative atrial fibrillation after coronary artery bypass grafting surgery.

To the Editor,

We read the article written by Geçmen et al. (1) titled “SYNTAX score predicts postoperative atrial fibrillation in patients undergoing on-pump isolated coronary artery bypass grafting surgery” published in Anatol J Cardiol 2016;16:655-61 with great interest. In their study, the authors reported that there was an independent association between age, chronic obstructive pulmonary disease, and SYNTAX score in predicting postoperative atrial fibrillation. We would like to emphasize some important points about this well-written study.

It has been demonstrated that volume overload could increase postoperative atrial fibrillation incidence by elevating intraatrial pressure (2). It has also been reported that increased cross-clamp and cardiopulmonary bypass time could increase risk for postoperative atrial fibrillation (3). We think that intraoperative factors should be taken into consideration when evaluating these patients.

Another important point is that body mass index, presence of metabolic syndrome, and waist-to-hip ratio are important markers for coronary artery disease, and moreover, obesity is associated with higher levels of inflammatory cytokines in circulation (4). As inflammation has been shown to cause deterioration in atrial conduction and predispose patients to develop atrial fibrillation postoperatively, authors should state these factors for each group (5).

In our opinion, to verify whether SYNTAX score is an important predictor of postoperative atrial fibrillation development, the above-mentioned points should be evaluated and included in the statistical analysis. It would be helpful if the authors provide this information.