P Wave Morphology

«Step 4:Heart axis

Step 6: QRS morphology»

Author(s)	J.S.S.G. de Jong, MD, A. Bouhiouf, Msc
Moderator	J.S.S.G. de Jong, MD
Supervisor
some notes about authorship

The P wave morphology can reveal right or left atrial stretch or atrial arrhythmias and is best determined in leads II and V1 during sinus rhythm.

Normal sinus rhythm with a positive p wave in leads I, II en AVF and a biphasic p wave in V1.

Altered P wave morfology is seen in left or right atrial enlargement.

The PTa segment can be used to diagnose pericarditis or atrial infarction.

Characteristics of a normal p wave:[1]
The maximal height of the P wave is 2.5 mm in leads II and / or III The p wave is positive in II and AVF, and bifasic in V1 The p wave duration is usually shorter than 0.12 seconds

Elevation or depression of the PTa segment (the part between the p wave and the beginning of the QRS complex) can result from Atrial infarction or pericarditis.

If the p-wave is enlarged, the atria are enlarged.

If the P wave is inverted, it is most likely an ectopic atrial rhythm not originating from the sinus node.

Examples

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  An example of normal sinus rhythm.
  

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  Another example of normal sinus rhythm.
  

References

1. Spodick DH, Raju P, Bishop RL, and Rifkin RD. Operational definition of normal sinus heart rate. Am J Cardiol. 1992 May 1;69(14):1245-6. DOI:10.1016/0002-9149(92)90947-w |