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Published on: December 11, 2019
Twelve-lead electrocardiogram: the advantages of an orderly frontal lead display including lead -aVR
Elena B Sgarbossa1, S Serge Barold, Sergio L Pinski
1Department of Internal Medicine/Cardiology, Rush Presbyterian-St. Luke's Medical Center, Chicago, IL, USA.
Background:
It is possible that efforts in ECG review by both young experienced clinicians are currently discouraged-and risk to be completely dismissed-by the conventional (ie, disorderly) display of the frontal plane leads, with lead aVR at -150 degrees.
Methods:
We reviewed studies on the usefulness of leads aVR and -aVR as well as on the history of the frontal leads in electrocardiography.
Results:
Lead aVR and particularly, lead -aVR, provide useful information when systematically analyzed. In addition, if lead -aVR is examined in its anatomically logical sequence, ie, aVL, I, -aVR, II, aVF, and III, the frontal plane of the 12-lead ECG is more easily understood. This "panoramic" or "orderly" display is in common use in countries such as Sweden, but it is rarely seen in the United States.
Conclusions:
ECG interpretation would be enhanced by displaying the limb leads in an orderly arrangement that starts with lead aVL and ends with lead III, and many ECG changes would be ideally displayed by a lead -aVR at 30 degrees.
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