Management of new-onset atrial fibrillation in critically ill patients: A national multicenter prospective cohort.

Background: New-onset atrial fibrillation (NOAF) occurs in 10% of intensive care unit (ICU) stays and worsens clinical outcomes. Despite its significance, no specific guidelines exist for the general ICU population. Our study investigates potential therapeutic approaches to NOAF, focusing on the rhythmic and haemodynamic outcomes associated with dedicated strategies.

Methods: In our prospective multicentre cohort study, we included adult patients admitted to 33 ICUs in France, exhibiting at least one episode of NOAF. Exclusions included permanent and post-cardiac/thoracic surgery AF. Data on demographics, clinical history, haemodynamic monitoring, and treatment choice for NOAF episodes were prospectively recorded. Heart rate, blood pressure, and rhythm status were assessed immediately before, at +5, +30, +60 minutes, and +24 hours after NOAF onset.

Results: Between May and December 2019, 453 ICU patients with 735 NOAF episodes were included. Therapeutic approaches included wait-and-see (n = 159 (22%)), IV fluid (n = 338 (46%)), magnesium (n = 299 (41%)), amiodarone (n = 295 (40%)), and beta blockers (n = 73 (10%)); alone or combined in 354 episodes (61%). Electric cardioversion, preferred for poor haemodynamic tolerance, was most effective for sinus rhythm conversion at +1 h (n = 17/30 (57%)). Heart rate and rhythm control were achieved at 87% (n = 588/674) and 80% (n = 259/654) at +24 h, with no significant difference between the strategies. On ICU discharge, 48 (13%) patients remained in AF; independent predictors included age, obesity, prior stroke, and hypercholesterolemia.

Conclusions: Therapeutic approaches for NOAF in ICU patients were heterogeneous, with nearly a quarter managed by a wait-and-see approach. Most strategies achieved rhythm and rate control within 24 hours. These findings highlight the frequent transient nature of NOAF episodes and support the need for individualized treatment decisions, particularly in unstable patients and those at risk for persistent AF. Trial registration ClinicalTrials.gov NCT03977883 (https://clinicaltrials.gov/study/NCT03977883?term=NCT03977883&rank=1).