Abstract 11723: Predictors of Post-Operative Atrial Fibrillation in Patients Undergoing Stress Echocardiography Prior to Noncardiac Surgery

Background: Atrial fibrillation (a-fib) occurs in up to 40% of patients after noncardiac surgery and is associated with increased risk of adverse outcomes. Practice guidelines recommend stress testing, including stress echocardiography (SE) to assess for coronary artery disease in selected high-risk patients prior to noncardiac surgery. The utility of using SE findings for predicting postoperative a-fib is unknown.

Hypothesis: Myocardial ischemia can contribute to arrhythmogenic potential; other echocardiographic variables are likely associated with a-fib. Findings on SE may identify patients at risk for a-fib after noncardiac surgery.

Aims: To determine if certain SE findings predict a-fib following noncardiac surgery.

Methods: The study included patients undergoing pharmacological and exercise SE before noncardiac surgery. The primary outcome was a-fib/flutter within 30 days after surgery. Multivariate analysis was adjusted for age, cardiovascular comorbidities, and markers of surgical risk.

Results: This analysis included 2,376 patients (mean age 68 +/- 7 years; 60% male); 1,986 patients had no known history of a-fib/flutter. Of these, 48 (2.4%) developed postoperative a-fib/flutter. In multivariate analysis, SE variables associated with development of new a-fib/flutter included left ventricular dilation (OR 2.11, p=0.049), increased left atrial volume (OR 1.19, p=0.045), and increased left ventricular mass index (OR 1.13, p=0.043) on rest images. The presence of ischemia or infarct on stress echocardiogram was not associated with postoperative a-fib/flutter. A total of 390 patients had a history of paroxysmal a-fib/flutter and were in sinus rhythm at the time of surgery. Of these, 90 (23%) experienced recurrent a-fib/flutter within 30 days of surgery. Multivariate analysis did not reveal any SE variables significantly associated with recurrence, including presence of myocardial ischemia or infarct at the time of SE.

Conclusions: All SE variables associated with postoperative a-fib following noncardiac surgery are available from resting images alone. Therefore, SE that includes comprehensive resting images may offer benefit in the pre-operative evaluation of selected patients.