Atrial Fibrillation in Heart Failure: a Therapeutic Challenge of Our Times

Abstract

Atrial fibrillation (AF) and heart failure (HF) are growing cardiovascular disease epidemics worldwide. There has been an exponential increase in the prevalence of AF and HF correlating with an increased burden of cardiac risk factors and improved survival rates in patients with structural heart disease. AF is associated with adverse prognostic outcomes in HF and is most evident in mild-to-moderate left ventricular (LV) dysfunction where the loss of "atrial kick" translates into poorer quality of life and increased mortality. In the absence of underlying structural heart disease, arrhythmia can independently contribute to the development of cardiomyopathy. Together, these 2 conditions carry a high risk of thromboembolism due to stasis, inflammation and cellular dysfunction. Stroke prevention with oral anticoagulation (OAC) remains a mainstay of treatment. Pharmacologic rate and rhythm control remain limited by variable efficacy, intolerance and adverse reactions. Catheter ablation for AF has resulted in a paradigm shift with evidence indicating superiority over medical therapy. While its therapeutic success is high for paroxysmal AF, it remains suboptimal in persistent AF. A better mechanistic understanding of AF as well as innovations in ablation technology may improve patient outcomes in the future. Refractory cases may benefit from atrioventricular junction ablation and biventricular pacing. The value of risk factor modification, especially with regard to obesity, sleep apnea, hypertension and diabetes, cannot be emphasized enough. Close interdisciplinary collaboration between HF specialists and electrophysiologists is an essential component of good long-term outcomes in this challenging population.

Keywords: Arrhythmias; Atrial fibrillation; Cardiomyopathy; Catheter ablation; Heart failure.

Figure 1

ESC and ACC/AHA/HRS guidelines for OAC therapy based on risk factors. ACC = American College of Cardiology; AHA = American Heart Association; ASA = acetylsalicylic acid; ESC = European Society of Cardiology; HRS = Heart Rhythm Society; INR = international normalized ratio; NOAC = novel oral anticoagulant; OAC = oral anticoagulation; VKA = vitamin K antagonist.

Figure 2

Management of patients with AF and HF based on current ACC and ESC guidelines. ACC = American College of Cardiology; AF = atrial fibrillation; AS = Aortic Stenosis; AV = atrioventricular; BB = beta blockers; CA = catheter ablation; CAD = coronary artery disease; CCB = calcium channel blockers; CRT-D = cardiac resynchronization therapy defibrillator; ESC = European Society of Cardiology; GDMT = guideline-directed medical therapy; HF = heart failure; HFpEF = HF with preserved ejection fraction; HFrEF = HF with reduced ejection fraction; HR = heart rate; ICD = implantable cardioverter defibrillator; IV = intravenous; LAA = left atrial appendage; LVEF = left ventricular ejection fraction; LVH = left-ventricular hypertrophy.