Pre-arrest atrial fibrillation and neurological recovery after cardiac arrest among hospitalized patients: A retrospective cohort study.

Background: New-onset atrial fibrillation (AF) is associated with an increased risk of stroke in hospitalized patients with severe sepsis. Post-cardiac arrest patients experience conditions similar to sepsis. This study investigated whether pre-arrest AF is associated with poor neurological recovery following in-hospital cardiac arrest (IHCA).

Methods: This single-centre retrospective study included patients experiencing IHCA between 2005 and 2020. Pre-arrest electrocardiograms (ECGs) were reviewed, including twelve-lead ECGs and ECG strips. New-onset AF was defined as AF absent on electronic health records (EHRs, including admission diagnosis, past medical history and hospitalization notes) but present on pre-arrest ECG. Without considering EHRs, AF-presence was defined as AF present on pre-arrest ECG.

Results: A total of 2466 patients were included, including 93 (3.8%) with new-onset AF and 131 (5.3%) with evidence of AF on pre-arrest ECG. The median age was 67.6 (interquartile range [IQR]: 22.3) years and the median CHA₂DS₂-VASc score was 3.0 (IQR: 3.0). A total of 405 (16.4%) patients survived to hospital discharge, with 228 (9.2%) patients achieving favourable neurological recovery. Multivariable logistic regression analysis indicated that both new-onset AF (odds ratio [OR]: .34, 95% confidence interval [CI]: .12-.94, p-value: .04) and AF-presence (OR: .35, 95% CI: .15-.85, p-value: .02) were inversely associated with favourable neurological recovery in the primary and sensitivity analyses, respectively.

Conclusions: Pre-arrest AF is a significant risk factor for poor neurological recovery following IHCA. Further research is needed to understand the underlying mechanisms, which could inform the development of strategies to improve outcomes in this patient subgroup.