[Pathogenesis and clinical significance of atrial fibrillation]

The authors review the current knowledge relating to the epidemiology, classification and pathogenesis of atrial fibrillation, and then discuss those cardiac electrophysiological changes that play roles in the initiation and/or maintenance of atrial fibrillation. They draw attention to the fact that atrial fibrillation is the most common cardiac arrhythmia in humans, its prevalence increasing continuously with the increase in average lifespan of the population. Atrial fibrillation doubles all-cause mortality, it gives rise to considerable haemodynamic alterations and clinical symptoms, and it is responsible for almost half of the cases of hospitalizations attributable to arrhythmia. Because of the great pathogenetic variety, the most important diagnostic task is to establish the nature of the underlying disease, the arrhythmia substrate, and the predisposing and triggering factors; this permits selection of the therapeutic procedure that is optimum for the given patient. The results of the most recent prospective randomized clinical trials indicate that, in certain groups of patients, it will no longer be absolutely necessary in the future to strive to restore and maintain sinus rhythm: effective oral anticoagulant treatment in combination with pharmacological ventricular rate control ensures the same survival chances and the same quality of life for the patient as those achieved in earlier years with the preferred sinus rhythm-preserving treatment strategy based on pharmacological and/or electrical cardioversions and prophylactic antiarrhythmic drug therapy.