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Characteristics of P wave in patients with sinus rhythm after maze operation

Hyo Eun Park1, Kyung-Hwan Kim, Ki-Bong Kim

  • 1Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.

Journal of Korean Medical Science
|May 4, 2010
PubMed

Insights

The Maze operation alters P wave morphology on electrocardiograms (ECGs), making diagnosis difficult. Post-Maze ECGs show small, monophasic P waves, differing from typical P mitrale patterns.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Medical Diagnostics

Background:

  • The Maze operation can alter P wave morphology on electrocardiograms (ECGs).
  • Accurate diagnosis of cardiac rhythm post-Maze operation is challenging due to altered P waves.
  • Systematic characterization of P wave morphology in sinus rhythm patients after Maze procedures is lacking.

Purpose of the Study:

  • To systematically evaluate P wave characteristics in patients with sinus rhythm after a modified Cox Maze operation.
  • To compare P wave morphology with echocardiographic findings.
  • To determine if P wave characteristics differ between patients with and without left atrial (LA) activity post-operation.

Main Methods:

  • Consecutive patients undergoing modified Cox Maze operation were enrolled.
  • Standard 12-lead ECG and echocardiography were performed 6 months post-operation in patients with sinus rhythm.
  • P wave axis, amplitude, and morphology were analyzed.

Main Results:

  • The average P wave axis was 65+/-30 degrees.
  • Average P wave amplitude was <0.1 mV in all leads, highest in V(1).
  • Monophasic, positive polarity P waves were most common (49%), differing from P mitrale and enlarged left atrium patterns.

Conclusions:

  • Post-Maze operation, P wave morphology exhibits a loss of the typical P mitrale pattern.
  • ECG findings include small amplitude, monophasic, and positive polarity P waves.
  • No significant differences in P wave characteristics or echocardiographic parameters were observed between patients with and without LA activity.

Keywords:
Atrial FibrillationElectrocardiogramMaze Operation

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