[Normal and abnormal atrial activation. An update with special reference to surface electrocardiogram].

Surface electrocardiogram is commonly used to evaluate the normal and abnormal activation of the atria. Interatrial conduction appears as the most important factor determining P wave duration and morphology during sinus rhythm. A good estimation of the interatrial conduction time can be obtained by a simple esophageal recording or by P wave duration on the surface electrocardiogram. A careful analysis of the ectopic atrial beats on the 12-lead electrocardiogram can identify the site of origin of the ectopic atrial beat. Surface electrocardiogram is commonly used in the classification of atrial flutter.