Atrial Fibrillation

Abstract

The last three decades have been characterized by an exponential growth in knowledge and advances in the clinical treatment of atrial fibrillation (AF). It is now known that AF genesis requires a vulnerable atrial substrate and that the formation and composition of this substrate may vary depending on comorbid conditions, genetics, sex, and other factors. Population-based studies have identified numerous factors that modify the atrial substrate and increase AF susceptibility. To date, genetic studies have reported seventeen independent signals for AF at fourteen genomic regions. Studies have established that advanced age, male sex, and European ancestry are prominent AF risk factors. Other modifiable risk factors, including sedentary lifestyle, smoking, obesity, diabetes mellitus, obstructive sleep apnea, and elevated blood pressure predispose to AF and each factor has been shown to induce structural and electrical remodeling of the atria. Both heart failure and myocardial infarction increase risk of AF and vice versa creating a feed forward loop that increases mortality. Other cardiovascular outcomes attributed to AF, including stroke and thromboembolism, are well established and epidemiology studies have championed therapeutics that mitigate these adverse outcomes. However, the role of anticoagulation for preventing dementia attributed to AF is less established. Our review is a comprehensive examination of the epidemiological data associating unmodifiable and modifiable risk factors for AF and of the pathophysiological evidence supporting the mechanistic link between each risk factor and AF genesis. Our review also critically examines the epidemiological data on clinical outcomes attributed to AF and summarizes current evidence linking each outcome with AF.

EvaluatioN of ApiXaban in strOke and systemic embolism prevention in patients with non‐valvular atrial fibrillation in clinical practice Setting in France, rationale and design of the NAXOS: SNIIRAM study

“…Atrial fibrillation (AF) can lead to significant mortality, morbidity, and cost. 1,2 Long-term prophylaxis with anticoagulation therapy is recommended to prevent stroke and systemic embolization in patients with AF presenting an independent risk factor for stroke. 3 Four non vitamin-K antagonists oral anticoagulants (NOACs) are currently available: the direct factor Xa inhibitors (rivaroxaban, apixaban, and edoxaban) and the direct factor IIa inhibitor (dabigatran).…”

Topographic characteristics of the left atrial medial isthmus

“…It is often accompanied by a wide array of complications ranging from frequent hospital admissions to increased risk of stroke and death. Structural, architectural, and/or electrophysiological abnormalities within the left atrium have been shown to trigger or perpetuate AF . A common and effective treatment option for patients with AF is catheter ablation of the arrhythmogenic substrate or of the conduction pathways .…”

“…Structural, architectural, and/or electrophysiological abnormalities within the left atrium have been shown to trigger or perpetuate AF. 1 A common and effective treatment option for patients with AF is catheter ablation of the arrhythmogenic substrate or of the conduction pathways. 2 One of the main objectives of left AF ablation is to enable the electrical disconnection (isolation) of the pulmonary venous ostia from the remaining atrial tissue.…”

Influence of atrial contraction dynamics on cardiac function

“…However, many fundamental questions remain on the influence of atrial mechanics on ventricular function, differences in predictive power between biventricular and whole heart models, and the physiological importance of atrioventricular interactions. In particular, atrial fibrillation is an increasingly common condition in which re-entrant waves in the atria interfere with normal heart rhythm [32,30,36]. Although contractile function during fibrillation is almost completely absent, the condition also causes long-term remodelling of the atria which persists even after normal heart rhythm is restored.…”