Arrhythmias

Abstract

The term “cardiac arrhythmia” encompasses disturbances of the normal rhythmic activity of the heart, including both the initiation and the conduction of the impulse. Recent methods of investigation have shown that arrhythmias are common in apparently normal individuals as well as in those with cardiac disease. Understanding arrhythmias and their treatment requires knowledge of the anatomy and electrophysiological properties of the specialised conducting system. Likewise, the selection of an anti-arrhythmic agent demands knowledge of its pharmacological properties, its site of action and its range of anti-arrhythmic activity. Rational therapy depends on establishing the correct diagnosis, which is often difficult since arrhythmias may be paroxysmal rather than sustained and infrequent rather than constant. The diagnosis of an arrhythmia in itself does not necessarily indicate a need for treatment. The decision to treat is influenced by the nature of the arrhythmia, the potential complications and the level of accompanying symptoms.