[Pathophysiology and clinical management of atrial flatter].

The authors review the current knowledge relating to the pathophysiology and treatment of atrial flutter, the most common supraventricular macroreentrant tachycardia. After an account of the historical and epidemiological data, the atrial tachycardia classification system based on the up-to-date North American + European consensus is presented. The main electrophysiological and electrocardiographic features of right atrial isthmusdependent typical and reverse typical flutter are detailed, as are those of the nonisthmus dependent, atypical forms. The electrophysiological connection between the very frequently coexisting atrial flutter and atrial fibrillation, and also the transitional form (flitter), are discussed. Following the clinical presentation, an account is given of the drug and non-pharmacological therapeutic modalities. It is pointed out that the recently-developed drugs with Vaughan Williams class 3 antiarrhythmic action, which block potassium channels and prolong atrial refractory period, are now primarily used (e.g. ibutilide, dofetilide). Effective means of terminating atrial flutter include transthoracic direct-current cardioversion (pretreated with antiarrhythmic = hybrid therapy) and transoesophageal or intraatrial overdrive pacing. It is stressed that the efficiency of prevention of atrial flutter with the antiarrhythmic drugs currently used even today is poor. Accordingly, the optimum mode of treatment of atrial flutter, which is primarily a method of first choice in special cardiac centres, is curative radiofrequency catheter ablation.