Atrial fibrillation and supraventricular tachycardias

Atrial fibrillation (AF) can cause significant symptoms and diminished quality of life, but, more importantly, is associated with increased risks of stroke, congestive heart failure, and mortality. It is the most common arrhythmia, and its prevalence continues to increase. Its prevalence in 2005 was 3.03 million and is projected to rise to 7.56 million by 2050. Already AF accounts for 350,000 annual hospitalizations and $6.65 billion dollars in annual healthcare costs in the United States. The medical management of atrial fibrillation can be challenging and needs to encompass evaluation and treatment of underlying causes, thromboembolic prophylaxis, and decision-making regarding rate or rhythm control. Supraventricular tachycardia (SVT) is a term that encompasses atrioventricular nodal reentrant tachycardia (AVNRT), atrioventricular reentrant tachycardia (AVRT), atrial tachycardia (AT), and inappropriate sinus tachycardia (IST). Although these disorders are generally considered benign, they can cause significant morbidity. In certain instances (Wolff-Parkinson-White syndrome), they can be life-threatening, and almost all tachyarrhythmias, if left untreated for extended periods of time, can lead to tachycardia-mediated cardiomyopathies. The prognostic implications for the patient, subsequent evaluation, and treatment may vary considerably depending on the etiology of the arrhythmia. The aim of this chapter is to provide a framework to successfully diagnose and manage these arrhythmias.