Association of New-Onset Atrial Fibrillation After Noncardiac Surgery With Subsequent Stroke and Transient Ischemic Attack
IMPORTANCE Outcomes of postoperative atrial fibrillation (AF) after noncardiac surgery are not well defined.
OBJECTIVE To determine the association of new-onset postoperative AF vs no AF after noncardiac surgery with risk of nonfatal and fatal outcomes.
DESIGN, SETTING, AND PARTICIPANTS Retrospective cohort study in Olmsted County, Minnesota, involving 550 patients who had their first-ever documented AF within 30 days after undergoing a noncardiac surgery (postoperative AF) between 2000 and 2013. Of these patients, 452 were matched 1:1 on age, sex, year of surgery, and type of surgery to patients with noncardiac surgery who were not diagnosed with AF within 30 days following the surgery (no AF). The last date of follow-up was December 31, 2018.
EXPOSURES Postoperative AF vs no AF after noncardiac surgery.
MAIN OUTCOMES AND MEASURES The primary outcome was ischemic stroke or transient ischemic attack (TIA). Secondary outcomes included subsequent documented AF, all-cause mortality, and cardiovascular mortality.
RESULTS Among 904 patients included in the matched analysis, the median age was 75 years (IQR, 67-82 years) and 51.8% of patients were men. Patients with postoperative AF had significantly higher CHA2DS2-VASc scores vs the no AF group (median, 4 [IQR, 2-5] vs 3 [IQR, 2-5]; P < .001). Over a median follow-up of 5.4 years (IQR, 1.4-9.2 years), there were 71 ischemic strokes or TIAs, 266 subsequent documented AF episodes, and 571 deaths, of which 172 were cardiovascular related. Patients with postoperative AF had a statistically significantly higher risk of ischemic stroke or TIA vs those with no AF. Patients with postoperative AF had statistically significantly higher risks of subsequent documented AF and all-cause death. No significant difference in the risk of cardiovascular death was observed for patients with and without postoperative AF.
CONCLUSIONS AND RELEVANCE Among patients undergoing noncardiac surgery, new-onset postoperative AF compared with no AF was associated with a significant increased risk of stroke or TIA. However, the implications of these findings for the management of postoperative AF, such as the need for anticoagulation therapy, require investigation in randomized trials.