512 Long-term survival in patients with post-operative atrial fibrillation after cardiac surgery: analysis from a prospective-cohort study

Aims Post-operative atrial fibrillation (POP AF) is frequent in patients who undergo cardiac surgery. However, its prognostic impact in the long-term remains unclear. Methods and results We followed for an average of 10 ± 3 years 1386 patients who underwent a variety of cardiac surgical procedures (cardiac transplantation and surgery for heart failure included) while they were in sinus rhythm. Among 1178 patents without a history of AF, 726 (62%) did not develop AF during the entire duration of the study and 452 (38%) developed new-onset POP AF during the first 30 peri-operative days after heart surgery. Other 125 patients with a positive history of paroxysmal or persistent AF were in sinus rhythm at the time of surgery and 87 of them (70%) developed POP AF. Finally, 83 patients had permanent AF when they underwent surgery. All-cause mortality was the primary outcome of the study. We tested the associations of potential determinants with all-cause mortality using univariable and multivariable statistical analyses by means of Cox proportional hazard models. Overall, 473 patients (34%) died during a long-term follow-up. Compared with patients who never developed AF, neither the patients with new-onset POP AF [adjusted HR = 1.31 (95% CI: 0.90–1.89); P = 0.1609], nor those with history of AF at the time of surgery (adjusted HR = 1.33, 95% CI: 0.71–2.49; P = 0.3736) showed a significantly increased risk of mortality (Figure 1). In new-onset POP AF patients, oral anticoagulation was not associated with mortality [adjusted HR = 1.13 (95% CI: 0.83–1.54), P = 0.4299]. Conclusions In this huge prospective cohort of patients who underwent different types of heart surgery, POP AF was not associated with an increased risk of mortality. In this setting, the role of long-term anticoagulation remains unclear.