Symptoms and Functional Status of Patients With Atrial Fibrillation: State of the Art and Future Research Opportunities

Abstract

Atrial fibrillation (AF) is the most common arrhythmia and is associated with increased risks of stroke, heart failure, dementia, and death.1–8 Because the number of elderly individuals will increase over the years to come, the prevalence of AF is predicted to increase dramatically.9 Symptoms are a major reason that patients with AF seek medical attention. Approximately two thirds of all emergency department visits with a primary diagnosis of AF result in hospital admissions.10 AF and its related symptoms therefore represent a major therapeutic challenge and burden to healthcare systems. The major goal of AF therapy is to reduce cardiovascular symptoms, morbidity, and mortality. Because the outcome of rate versus rhythm control therapies is similar,11,12 the degree of symptoms related to the arrhythmia is a major consideration during the selection of a treatment strategy. Given the cost and potential complications related to medications and ablation techniques used for rhythm control, an accurate evaluation of the symptoms and functional status of patients with AF is crucial. Despite the fact that AF was described in humans in 1906,13 no standardized assessment of symptoms or functional status has been accepted as the gold standard. The management of AF stands in marked contrast to heart failure, for which there is a straightforward and widely used symptom scale. Although AF and heart failure often coexist and both may cause similar symptoms, the New York Heart Association functional class was not developed for use in AF per se. The lack of a standardized approach may result in part from the complex clinical decision-making process in patients with AF. Challenges arise because symptoms related to AF are highly variable, not only between patients but also in individual patients at different time points. The most common symptoms include palpitations, chest pain, and a reduction in exercise tolerance. Yet, ≈15% to 30% of patients with AF are asymptomatic.14–16 The relation between symptoms or impaired functional status and the onset or recurrences of the arrhythmia is not always obvious. In addition, symptoms and impaired functional status may not be specific for AF because other cardiovascular conditions and risk factors for AF may cause similar symptoms. Furthermore, the magnitude of symptoms and functional status improvement attributable to specific AF therapies varies widely. The aim of our review is to discuss the symptomatology and functional status of individuals with AF. We highlight current knowledge about the patient's experience of AF, as well as the pathophysiology and prognostic implications of symptoms related to AF. In addition, we provide an overview of the most frequently used tools to assess symptoms and functional status. Finally, we summarize current gaps in the literature on AF symptomatology and underscore important potential research directions.