Treatment of atrial fibrillation

Abstract

Introduction: Atrial fibrillation (AF) is the most common, sustained rhythm disturbance. The prevalence of AF is increasing as people live longer. Common conditions such as hypertension and ischaemic heart disease play an important role in the development of AF. The presence of AF is associated with increased morbidity and mortality from stroke and heart failure, particularly in patients with structural heart disease.

Sources of data: This article provides evidence-based information on the key aspects of managing AF which is based on major guidelines, landmark clinical trials and meta-analyses.

Areas of agreement: It is well recognized that both rate control and rhythm control are important strategies for the management of AF, but each approach should be chosen according to individual patient circumstances. A vast majority of elderly, relatively asymptomatic patients will benefit from ventricular rate control. Embolic stroke remains a major complication of AF. Yet, anticoagulation with warfarin remains underprescribed, especially in the elderly due to the presumed risk of bleeding. The technique of catheter ablation continues to improve and is generally successful in younger patients with relatively normal hearts.

Areas of controversy: There are clinically relevant differences among published schemes designed to stratify stroke risk in patients with AF. The CHADS2 score is currently the most simple system to give some initial estimate of stroke risk in AF patients, but could significantly underestimate this risk, particularly in those who fall in the 'intermediate' risk category.

Growing points and areas timely for developing research: Novel antiarrhythmic agents, including atrial specific agents with improved efficacy and safety profile, are currently under development. New antithrombotic agents with efficacy similar to warfarin which do not require regular INR testing appear to be promising, but there are lack of data about their long-term safety. There is increasing evidence that inflammation and fibrosis may play a major role in the initiation and maintenance of AF. Statins by means of their pleotropic effects and angiotensin-converting enzyme inhibitors and angiotensin receptor blockers by preventing atrial remodelling may prove useful in preventing the development of AF. However, there is insufficient evidence to expand the use of these agents to a wider patient population at risk of AF. It needs to be seen if strategies towards primary and secondary prevention with treatment of underlying heart disease and modification of risk factors have a larger effect than specific interventions in preventing the burden of AF in the general population.