From the Guidelines

Yes, atrial fibrillation (AF) can cause decompensated heart failure (HF).

AF can lead to a decrease in cardiac output due to loss of synchronous atrial mechanical activity and irregular ventricular response 1.
A persistently elevated ventricular rate during AF may adversely increase mitral regurgitation and produce dilated ventricular cardiomyopathy (tachycardia-induced cardiomyopathy) 1.
The relationship between HF and AF is complex, with AF being a risk factor for developing HF, and patients with HF being more likely to develop AF over time 1.
AF is a strong independent risk factor for subsequent development of HF, and the prognosis of patients hospitalized with HF is suboptimal 1.
Common factors that precipitate acute decompensated HF include AF and other arrhythmias, highlighting the importance of managing AF in patients with HF 1.

The diagnosis of AF-mediated tachycardiomyopathy should be considered in patients with new-onset or worsening HF in the setting of AF with rapid ventricular response 1.
Rhythm control or rate control may be recommended for patients who develop HF as a result of AF and rapid ventricular rate 1.
Beta-blockade is recommended as the first-line rate-control medication, with digoxin as an adjunctive medication 1.

From the Research

Atrial fibrillation (AF) is the most common sustained arrhythmia worldwide and has a strong association with heart failure (HF) 2.
The relationship between AF and HF is complex, and it is often unclear if HF is the cause or consequence of AF 2.

Atrial fibrillation is an independent risk factor for heart failure hospitalization in heart failure with preserved ejection fraction (HFpEF) 3.
Patients with AF have a higher risk for HF hospitalization than their counterparts without AF, with a hazard ratio of 2.53 and 2.91 in two different analyses 3.
Right ventricular dysfunction is a strong predictor of developing AF in acutely decompensated heart failure patients, with an odds ratio of 4.45 4.

Atrial fibrillation and mitral regurgitation are closely interrelated in the setting of heart failure, with AF being more likely in those with higher mitral regurgitation severity regardless of HF subtype 5.
The association between AF and 1-year mortality was noted in patients with HFpEF, but not in those with heart failure with reduced ejection fraction (HFrEF) 5.

Atrial fibrillation is particularly common in patients with HFpEF, with a prevalence ranging around 40-60% 6.
Treatment with SGLT2 inhibitors has been shown to result in a lower risk of worsening heart failure or cardiovascular death than placebo in patients with HFpEF, regardless of the presence of AF 6.
Early rhythm-control therapy has been associated with a lower risk of adverse cardiovascular outcomes than usual care among patients with recent AF and cardiovascular conditions, including those with HF 6.