ABC of Atrial Fibrillation: DRUGS FOR ATRIAL FIBRILLATION

Abstract

One of the most important principles of using antiarrhythmic drugs for controlling any arrhythmia is to treat only patients who are symptomatic, have malignant arrhythmias (such as ventricular fibrillation), or are haemodynamically compromised (for example, with hypotension or heart failure). If a patient has only mild and infrequent symptoms, treatment with antiarrhythmic drugs should be avoided. This strategy is justified by evidence of substantial morbidity associated with such treatment and worsened long term prognosis, particularly if class I agents are used. Many antiarrhythmic drugs also depress cardiac function and may precipitate heart failure, and most can aggravate or cause an arrhythmia (arrhythmogenesis or proarrhythmic effect). #### Vaughan-Williams classification of antiarrhythmic drugs Antiarrhythmic drugs can be used for rate control of chronic atrial fibrillation, cardioversionof atrial fibrillation to sinus rhythm, maintenance of sinus rhythm after cardioversion, and control of symptoms (including as a prophylaxis in paroxysmal atrial fibrillation). Antithrombotic prophylaxis with warfarin or aspirin should also be given. Prescribing habits for atrial fibrillation,however, vary greatly, perhaps reflecting uncertainty about what the best drug is and a lack of scientific evidence from controlled trials. #### An approach to drug management of atrial fibrillation Paroxysmal atrial fibrillation