Postoperative atrial fibrillation in patients undergoing noncardiac surgery in Alberta: a retrospective cohort study
Y Smereka, R Sandhu, D Dover, F Mcalister, S Van Diepen, P Kaul, J EzekowitzAbstract
Background
Postoperative atrial fibrillation (POAF) is the most common rhythm disorder after noncardiac surgery (NCS), yet its predictors, outcomes, and treatment patterns remain incompletely defined.
Purpose
To determine the incidence, predictors, and clinical outcomes associated with POAF, and to characterize perioperative cardiovascular medication use.
Methods
Retrospective cohort of Albertan adults without prior AF who underwent inpatient NCS (2016-2023). Primary outcome was 30 day POAF (new-onset after NCS) and secondary outcomes were longer-term events (31-365 days after NCS): myocardial infarction (MI), stroke/transient ischemic attack (TIA), heart failure (HF); all-cause mortality; total hospital length of stay (LOS); AF encounters; and new-onset AF. Multivariable logistic regression models were used to examine the association between POAF and its predictors; and Cox regression analysis was used to examine the association between POAF and the long-term events. We examined cardiovascular medications administered preoperatively and up to1 year postdischarge.
Results
Among the 70,618 patients who underwent NCS without prior AF, POAF occurred in 4.9% with the highest incidence following colorectal, thoracic, vascular, endovascular, gastrointestinal endoscopy, and bronchoscopy procedures. Overall, 37.5% of patients who experienced POAF had documented AF encounters from 31 to 365 days after NCS. Among patients who did not experience POAF, 5.2% developed new-onset AF between 31 and 365 days after NCS. POAF predictors are shown in Figure 1a and POAF-related outcomes in Figure 1b. Oral anticoagulants (OACs) use rose from 18.0% preoperatively to 47.2% by 30 days in patients with POAF. Among patients with POAF, 87.3% had baseline CHA2DS2-VASc scores ≥2; OAC use increased with higher scores, from 36.6% at 7 days to 63.9% at 1 year for score 2, and from 38.1% to 70.2% for scores ≥3.
Conclusions
Approximately, 1 in 20 patients without prior AF undergoing NCS had POAF which was associated with higher long-term risk of stroke/TIA, HF, and mortality. Although OAC use rose over time, uptake was suboptimal. Further studies are needed to define optimal POAF monitoring and strategies to reduce cardiovascular risk.