P-wave complexity in normal subjects and computer models
Mark Potse1, Theo A R Lankveld2, Stef Zeemering3
1Department of Biomedical Engineering, Cardiovascular Research Institute Maastricht, Maastricht University, Universiteitssingel 50, 6229 ER Maastricht, The Netherlands.
Background:
P waves reported in electrocardiology literature uniformly appear smooth. Computer simulation and signal analysis studies have shown much more complex shapes.
Objective:
We systematically investigated P-wave complexity in normal volunteers using high-fidelity electrocardiographic techniques without filtering.
Methods:
We recorded 5-min multichannel ECGs in 16 healthy volunteers. Noise and interference were reduced by averaging over 300 beats per recording. In addition, normal P waves were simulated with a realistic model of the human atria.
Results:
Measured P waves had an average of 4.1 peaks (range 1-10) that were reproducible between recordings. Simulated P waves demonstrated similar complexity, which was related to structural discontinuities in the computer model of the atria.
Conclusion:
The true shape of the P wave is very irregular and is best seen in ECGs averaged over many beats.
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