Role of Implantable Atrial Defibrillators in the Treatment of Atrial Fibrillation

Abstract

Atrial fibrillation (AF) is an important epidemiological problem, and is a major supraventricular arrhythmia1,2. Its consequences are mainly the development of heart failure, and an established relationship with stroke. Apart from preventing these complications, treatment is aimed at slowing ventricular rate, converting the arrhythmia to sinus rhythm, and to maintaining sinus rhythm after conversion. Conversion can be performed with drugs or by electrical means. Drugs are moderately effective, except when AF is of recent onset3,4. When AF is sustained, or has existing for a longer period of time, pharmacological conversion becomes more difficult. Some hope exists that newer class III drugs will become effective for this indication, but it has to be accepted that, with the proarrhythmia as observed in recent trials, conversion remains an in-hospital procedure5. Furthermore, dofetilide terminated AF only 31% of the patients, comparable to the efficacy reported for ibutilide5,6. Torsades de pointes were the main adverse events, but regular wide QRS tachycardia, probably with aberrancy, was also reported5–7.