Atrial fibrillation is associated with poor clinical trajectory of COVID-19
Authors: Stjepan Jurisic S.J , Komminoth M.K , Wiggli B.W , Bertschi D.A.B , Koepfli P.K , Vranjic I.V , Friedl A.F , Contartese J.C , Fontana F.F , Schmid H.S , Rutishauser J.R , Gebhard C.G , Todorov A.T , Beer J.B , Patriki D 
Published: October 2021

Abstract

Background
Atrial fibrillation (AF) has been described as a common cardiovascular manifestation in patients suffering from coronavirus disease 2019 (COVID-19) and is discussed to be a potential risk factor for a poor clinical course. AF is also already known to be associated with increased risk for all cause death.

Purpose
In the present study we sought to investigate the impact of AF on the clinical trajectory of patients suffering from COVID-19.

Methods
We included all patients hospitalized due to COVID-19 in 2020 in our Hospital. A poor clinical trajectory was defined as transfer to intensive care unit (ICU), intermediate care unit (IMC) or death from any cause. Initial ECGs were analyzed in consensus by two experienced readers. First, we compared patients with poor clinical trajectory vs. good clinical course. Secondly, the study population was categorized into two groups with or without AF on admission. A subgroup analysis was performed to differentiate between new onset AF and patients with known history of AF. To compensate for confounders (age, BMI, known cardiomyopathy (CMP), known coronary artery disease (CAD), chronic airway disease, renal insufficiency, diabetes, arterial hypertension and sex), a full clinically validated multiple logistic regression model with poor clinical trajectory as dependent target variable was performed.

Results
From our enrolled 666 patients in 2020 (58% male, average age: 66 (IQR:58–80)) 223 patients (33.5%) experienced a poor clinical course. 179 (27%) patients were transferred to IMC/ICU and 86 (13%) patients died. All in all, patients with poor clinical trajectory were more frequently male (70% vs. 52%; P&lt;0.001), older (71±14 vs. 64±20; P&lt;0.001) and had significantly more co-morbidities such as CAD, CMP, hypertension and diabetes in comparison to patients with a good clinical course. 96 (14.4%) had AF on admission. Among these 37.5% had new-onset AF, which showed similar baseline characteristics as patients without AF. Indeed, patients with COVID-19 and new onset AF were more likely to die (25% vs 12%; P=0.038), or be in need for ICU/IMC (25% vs. 62%; P&lt;0.001) and therefore experienced a poor clinical trajectory more frequently (75% vs. 31%; P&lt;0.001) with a confounder adjusted OR of 5.89.
In the subgroup analysis of all patients with AF on admission. Patients with new onset of AF had significantly more underlying CMP, Diabetes and chronic airways disease. While mortality was not higher in patients with new onset of AF, IMC/ICU transfers (62% vs 24%; P&lt;0.001) and as a result poor clinical trajectory (75% vs 40%; P=0.001) was significantly increased in comparison to patients with known AF.

Conclusion
In patients suffering from COVID-19, new onset of AF on admission was associated with a poor clinical course and higher in-hospital mortality.

Funding Acknowledgement
Type of funding sources: None.