Atrial fibrillation (AFib) is an irregular and often rapid heart rhythm that can increase the risk of stroke, heart failure, and other complications. In critical care, healthcare providers work to control the heart rate, restore normal sinus rhythm when feasible, and administer treatments to prevent complications like blood clots. The treatment of AFib in this setting typically involves heart rate reducing agents that allow the patient to convert to sinus rhythm. Close monitoring and specialized interventions are integral to managing atrial fibrillation effectively.
Atrial Fibrillation
Atrial Fibrillation and Heart Failure
Atrial Fibrillation and Heart Failure
Atrial fibrillation (AFib) is a common supraventricular arrhythmias in patients with left ventricular (LV) dysfunction.
These arrhythmias start in the atria or AV node and can worsen heart failure by increasing the heart rate and reducing the time for the ventricles to fill with blood.1
Over 20% of patients with heart failure exhibit atrial fibrillation.
Interaction Between Atrial Fibrillation (AFib) and Heart Failure (HF)
AFib is often associated with a rapid ventricular response during the worsening of heart failure.1
HF creates an electrically unstable environment within the atria through structural and neurohormonal remodeling, making them prone to AFib.
Hemodynamic and atrial remodeling changes include: (1) increased atria pressure and stretch, and (2) atrial fibrosis and scarring which slows or blocks conduction.2
Neurohormonal and electrical changes include: (1) activation of the sympathetic nervous system (catecholamines) and the RAAS (angiotensin), and (2) abnormal atrial myocyte calcium handling leading to intracellular calcium overload and disrupted electrical impulses.3
Atrial fibrillation can significantly compromise cardiac ability to pump efficiently, reducing cardiac output. The coexistence of HF and AFib is associated with worse prognosis, increased hospitalizations, and higher mortality compared to having either condition alone. Therefore, aggressive management of both the underlying HF and the AFib rhythm/rate is crucial for patient outcomes.
The relationship between arrhythmias and left ventricular dysfunction is complex. HF causes arrhythmias and arrhythmias causes HF:
Structural changes from HF make the heart more prone to atrial and ventricular arrhythmias.
Persistent and rapid heart rhythms like AFib can worsen left ventricular dysfunction, known as arrythmia-induced cardiomyopathy (AIC).
Management Approaches for Heart Failure
In recent decades, advancements achieved in pharmacological treatment have significantly improved the prognosis of patients with chronic HF.
Guideline recommended medications for the improvement of outcomes in chronic heart failure with reduced ejection fraction (HFrEF) include: ACEi (angiotensin-converting enzyme inhibitor) or ARB (angiotensin receptor blocker) or ARNi (angiotensin receptor‐neprilysin inhibitor), MRA (mineralocorticoid receptor antagonist), SGLT2i (sodium‐glucose cotransporter‐2 inhibitor) and diuretics.6,7
Beta-blockers are cornerstone therapy for HFrEF, for the improvement of outcomes and prognosis by blocking sympathetic activity, reducing catecholamine release, slowing heart rate lowering blood pressure, reducing the heart’s workload and oxygen demand, and counteracting the cardiotoxic effects of high catecholamine levels. Efficacy for HFpEF is not well-estblished.6-8
References:
- Nagai R, Kinugawa K, Inoue H, et al.. Urgent management of rapid heart rate in patients with atrial fibrillation/flutter and left ventricular dysfunction: comparison of the ultra-short-acting β1-selective blocker landiolol with digoxin (J-Land Study). Circ J. 2013;77(4):908-16. doi: 10.1253/circj.cj-12-1618. Epub 2013 Mar 15. PMID: 23502991.
- Ferreira JP, Santos M. Heart Failure and Atrial Fibrillation: From Basic Science to Clinical Practice. International Journal of Molecular Sciences. 2015; 16(2):3133-3147.
- Kotecha D, Piccini JP, Atrial fibrillation in heart failure: what should we do?, Eur Heart J, 2015; 36(46): 3250–3257.
- Park KL, Anter E. Atrial Fibrillation and Heart Failure: A Review of the Intersection of Two Cardiac Epidemics. J Atr Fibrillation. 2013 Jun 30;6(1):751. doi: 10.4022/jafib.751.
- Gorenek B, Halvorsen S, Kudaiberdieva G, et al. Atrial fibrillation in acute heart failure: A position statement from the Acute Cardiovascular Care Association and European Heart Rhythm Association of the European Society of Cardiology. Eur Heart J Acute Cardiovasc Care. 2020 Jun;9(4):348-357. doi: 10.1177/2048872619894255.
- McDonagh TA, Metra M, Adamo M, et al. ESC Scientific Document Group. Focused Update of the 2021 ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure. Eur Heart J. 2023 Oct 1;44(37):3627-3639. doi: 10.1093/eurheartj/ehad195. Erratum in: Eu. Heart J. 2024 Jan 1;45(1):53. doi: 10.1093/eurheartj/ehad613. PMID: 37622666.
- Heidenreich PA, Bozkurt B, Aguilar D, et al.. AHA/ACC/HFSA Guideline for the Management of Heart Failure: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. J Am Coll Cardiol. 2022 May 3;79(17):e263-e421. doi: 10.1016/j.jacc.2021.12.012. Epub 2022 Apr 1. Erratum in: J Am Coll Cardiol. 2023 Apr 18;81(15):1551. doi: 10.1016/j.jacc.2023.03.002. PMID: 35379503.
- Xie L, Chen J, Li Y, et al. Beta-blocker administration within 24 hours after admission to the intensive care unit and mortality in critical heart failure patients: a retrospective analysis from the MIMIC-IV database. Front. Pharmacol 2025;. 16:1514138. doi: 10.3389/fphar.2025.1514138