eComment. Preoperative atrial fibrillation and outcome in patients undergoing on-pump or off-pump coronary bypass surgery.

E et al. Off-pump or on-pump coronary artery bypass grafting at 30 days. versus on-pump coronary artery bypass grafting for ischaemic heart disease. A meta-analysis of large randomized trials for mid-term major cardio-and cerebrovascular events following off-pump versus on-pump coronary artery bypass grafting. Long-term follow-up of morbidity and mortality after aortic valve replacement with a mechanical valve pros-thesis. The significance of preoperative atrial fibrillation in patients undergoing cardiac surgery: preoperative atrial fibrillation—still underestimated opponent. the outcome of on-pump versus off-pump coronary artery bypass grafting in patients with preoperative atrial fibrillation. et al. Percutaneous coronary intervention versus coronary-artery bypass grafting for severe coronary artery disease. Predictors and impact of postoperative atrial fibrillation on patients' outcomes: a report from the ROOBY trial. et al. New-onset atrial fibrillation predicts long-term mortality after coronary artery bypass graft. Böning et al. [1] present important work with regard to the increased risk of pre-operative atrial fibrillation (AF) with regard to mortality in patients undergoing coronary artery bypass grafting. Böning et al. conclude that "AF at admission is a significant risk factor for elderly patients undergoing coronary bypass grafting", however they do not define the age range for elderly patients. Our institution is a very large off-pump institution (N = 8875 cases to date [2,3]). Our data in patients aged over 65 years [N = 6395 (on-pump N = 4603; off-pump N = 1792)], identifies on multivariate analysis that pre-operative AF is a significant factor determining in-hospital mortality and long-term survival. Interestingly, our in-hospital mortality was 3.4% in patients aged over 65 years, who had preoperative AF, and 2.6% in those in sinus rhythm preoperatively — a non-significant difference (P = 0.1) compared to the significant difference findings presented by Böning et al. Böning et al. documented the number of packed red blood cells transfused. Unfortunately, no multivariate analysis was performed. We have previously identified that in patients who received no transfusion, preoperative AF is still a significant risk factor for in-hospital mortality and reduced long-term survival [4], implying transfusion that is associated with warfarin therapy is not a confounding factor. Unfortunately, no long-term data is presented in the manuscript. We have previously demonstrated that in young patients, defined as age <65 years old at time of surgery, that preoperative AF is a significant factor associated with in-hospital death and long-term survival [5]. We thank Böning et al. for their important work, and congratulate them on conducting …