“Incidence, predictors, and outcomes of new-onset atrial fibrillation in critically ill patients with sepsis,” AJRCCM, 2017, Netherlands
Question: What is the incidence of new-onset atrial fibrillation/atrial flutter (AF) in ICU patients with sepsis and is the development of AF associated with mortality?
Study Type: Sub-study of a prospective cohort study at two hospitals in the Netherlands
Study Population: Adults admitted to the ICU with sepsis over a two-year period were included. Exclusion criteria included a history of AF, recent cardiotomy, or cardiac arrest.
Study Groups: AF detection based on hourly recordings of the rhythm observed by the bedside nurse. AF needed to be sustained for 1 hour or require pharmacologic treatment or cardioversion to be included.
Primary Outcome: Incidence of new-onset AF
Results: 1,782 patients included in analysis. Notable patient characteristics: Age (»62), immunosuppression (26%), malignancy (10%), lung as source of infection (62%), mechanical ventilation (83%), surgical admission (23%), 90-day mortality (34%). The overall incidence of AF was 23%. For patients with septic shock, the risk of AF was 40%. The most common treatments administered were amiodarone (71%), magnesium (69%), electrical cardioversion (11%), and sotalol (8%). After multivariable regression, AF remained associated with ICU mortality (HR 2.10; 95% CI, 1.61-2.73). An AF risk score was developed (the “SAFE” score) and validated in an independent cohort. The score can be accessed here: https://safescore.shinyapps.io/safe/.
Caveats: Unmeasured confounding a concern in observational studies, unable to prove AF has causal role in poor outcomes, relied on identification and classification of arrhythmia by bedside nurse so possible missed or misclassified episodes, data collected from only two centers.
Take-home Point: New-onset AF is common in ICU patients with sepsis and may lead to increased mortality.
Commentary
– Part of a growing body of literature helping to describe the incidence and significance of new-onset AF in critical illness. Certainly notable that the incidence of AF in septic shock approaches 50%
– The SAFE score still needs to be independently validated, but it is an interesting attempt by the authors to come up with a way to predict the development of sepsis-induced AF (and, in doing so, potentially identify a group of septic patients to enroll in trials of AF prophylaxis).