Associations of Atrial Fibrillation After Noncardiac Surgery With Stroke, Subsequent Arrhythmia, and Death A Cohort Study

Background: Postoperative atrial fibrillation (AF) after non-cardiac surgery confers increased risks for ischemic stroke and transient ischemic attack (TIA). How outcomes for post-operative AF after noncardiac surgery compare with those for AF occurring outside of the operative setting is unknown. Objective: To compare the risks for ischemic stroke or TIA and other outcomes in patients with postoperative AF versus those with incident AF not associated with surgery. Design: Cohort study. Setting: Olmsted County, Minnesota. Participants: Patients with incident AF between 2000 and 2013. Measurements: Patients were categorized as having AF occurring within 30 days of a noncardiac surgery (postopera-tive AF) or having AF unrelated to surgery (nonoperative AF). Results: Of 4231 patients with incident AF, 550 (13%) had postoperative AF as their first-ever documented AF presen-tation. Over a mean follow-up of 6.3 years, 486 patients had an ischemic stroke or TIA and 2462 had subsequent AF; a total of 2565 deaths occurred. The risk for stroke or TIA was similar between those with postoperative AF and nonoperative AF (absolute risk difference [ARD] at 5 years, 0.1% [95% CI,-2.9% to 3.1%]; hazard ratio [HR], 1.01 [CI, 0.77 to 1.32]). A lower risk for subsequent AF was seen for patients with post-operative AF (ARD at 5 years,-13.4% [CI,-17.8% to -9.0%]; HR, 0.68 [CI, 0.60 to 0.77]). Finally, no difference was seen for cardiovascular death or all-cause death between patients with postoperative AF and nonoperative AF. Limitation: The population consisted predominantly of White patients; caution should be used when extrapolating the results to more racially diverse populations. Conclusion: Postoperative AF after noncardiac surgery is associated with similar risk for thromboembolism compared with nonoperative AF. Our findings have potentially impor-tant implications for the early postsurgical and subsequent management of postoperative AF.