Diagnostic criteria

  Heart rate (ventricular rate) is between 60-100/minute.

  QRS width is
< 120 msec (normal).

  P waves may be present or absent.

      P waves may not be related to the QRS complexes.

      P waves may be located before, during or after the QRS complex (due to retrograde conduction).

  Usually, some degree of
atrioventricular (AV) block accompanies.



Causes

  Digoxin intoxication

  Acute myocardial infarction

  Acute pulmonary embolism

  Hypoxia

  Cardiomyopathy

  After cardiac valve surgery

  After para-Hisian accessory pathway cryoablation




References

  Proc (Bayl Univ Med Cent) 2009;22:371-372.

  J La State Med Soc 2011 ;163:69-70.

  Europace 2011;13:135-137.





ECG 1. The ECG above belongs to a woman with long-standing chronic systemic arterial hypertension.
She had experienced syncope 4 days ago due to acute pulmonary embolism.
The ECG shows accelerated junctional rhythm. Heart rate (ventricular rate) is about 83/minute. There is also ectopic atrial
tachycardia. The atrial rate is about 165/minute.
P waves are not related to the QRS complexes: complete AV block.
The increased voltage in this ECG suggests left ventricular hypertrophy.

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ECG 2. The ECG above belongs to a 51 years-old woman.
Retrograde inverted P waves with short PR intervals and a heart rate of 94/minute denotes to accelerated junctional rhythm.

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ECG 3. Above is an ECG from a 31 years-old woman.
P waves are not seen in their usual locations.
No
P wave is followed by a QRS complex, but every QRS complex is followed a P wave.
The impulses originate from the AV node and retrogradely stimulate the atria.
Therefore
retrograde P waves are recorded as negative waves.
Since the ventricular rate is above > 60/minute, the rhythm is "accelerated" nodal rhythm.

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