P Wave Morphology

«Step 4:Heart axis

Step 6: QRS morphology»

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.

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 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 |