Cardiac arrhythmias. An update on identification and therapy.

Cardiac arrhythmias result from conduction block, abnormal impulse formation, or a combination of both. The decision to treat arrhythmias depends on symptoms, hemodynamic problems, the presence or absence of organic heart disease, and the presence of malignant arrhythmias. Holter monitoring, treadmill exercise testing, and electrophysiologic stimulation can facilitate identification. Control involves correction of precipitating or contributing factors and selection of an appropriate antiarrhythmic drug or surgical technique.