Axis Determination ECG Interpretation

Part I

  • The direction of the ventricular depolarization (QRS complex) is analyzed.
  • Refer to lead I and aVF each time
  • If the majority of the QRS complex is positively deflected in both views, this is referred to as “normal axis”.
12lead ecg image 3
12lead ecg image 4

Part II

If lead I is positive and aVF is negative, this is ‘left axis deviation”

12lead ecg image 5
12lead ecg image 6

Part III

If lead I is negative and aVF is positive, this is “right axis deviation”.

12lead ecg image 23
12lead ecg image 24

Part IV

If lead I is negative and aVF is negative, this is extreme right axis deviation aka indeterminate.

12lead ecg image 7
12lead ecg image 8

Authors and Sources

Authors and Reviewers


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