Common Diagnostic Criteria for Left and Right Atrial Abnormalities

Left Atrial Abnormality

  • Prolonged P wave duration of >120 msec in lead II
  • Prominent notching of the P wave, usually most obvious in lead II, with an interval between the notches of >40 msec (p mitrale)
  • Ratio between the duration of the P wave in lead II and the duration of the PR segment of >1.6
  • Increased duration and depth of the terminal negative portion of the P wave in lead V1 (the P terminal force) so that the area subtended by it exceeds 0.04 mm-sec (Morris index)
  • Leftward shift of the mean P wave axis to between -30 and +45 degrees Continue reading