Diagnostic criteria

  The presence of two consecutive atrial premature beats.

  The shape of the P waves of the premature beats is different from that of the sinus P.

  Premature atrial beats are generally conducted to the ventricles in a normal fashion and result in narrow QRS complexes.

  If the premature beat comes very early, it may be conducted to the ventricles with aberration resulting in a wide QRS complex.

ECG 1. Atrial couplet observed during Holter recording.
The QRS complexes of the premature beats are narrow and have
P waves
with shapes different than those of the sinus beats. To the left, a ventricular premature beat (VPS) is observed with a
full compensatory pause: 632 + 648 = 546 + 734.

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ECG 2. The ECG above was recorded during acute inferior wall myocardial infarction. Atrial couplet is seen.
P waves of the atrial extrasystoles have a different configuration than sinus P waves.

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