Stroke prevention in atrial fibrillation: we can do better.

Abstract

Atrial fibrillation (AF), an irregular and often rapid cardiac rhythm, is the most common sustained cardiac dysrhythmia. Prothrombotic changes in the atrium encourage local clot formation with potential for embolisation to the cerebral circulation, conferring a fivefold increase in risk of stroke. It is estimated that one in five strokes, and one in three over the age of 80 years, are directly attributable to AF. Strokes that are due to AF also have a much worse outcome, with significantly higher mortality rates and greater long-term disability. At the same time we have very effective preventive treatments, with anticoagulants reducing the risk of ischaemic stroke by around 70%. Reflecting this, National Institute for Health and Care Excellence (NICE)1 and European consensus2 guidance recommends that we offer structured risk assessment followed by anticoagulation for people identified as at high risk. This pathway of diagnosis, assessment, and management does not generally require specialist input and should be regarded as essential primary care. So how well are we doing and could we do better? The prevalence of diagnosed AF in England is 1.6%. Modelled estimates suggest the real prevalence is much higher at 2.4%, indicating that a third of individuals with AF, around half a million people in England or 2500 in the average clinical commissioning group (CCG), are undiagnosed and therefore untreated. AF prevalence increases sharply with age, with 80% of cases occurring in people >65 years.3 AF sometimes causes symptoms that …