12-Lead Electrocardiography

a comprehensive course

Adam Thompson, EMT-P, A.S.

Axis: The

Quadrant

Method

Quadrant Method

• Much easier to do. • Faster and more practical for rapid

interpretation. • Does not give you a very close

estimate.

Quadrant Method

ERAD LAD

RAD Normal

180 0

-90

90

Quadrant Method

ERAD LAD

RAD Normal

- I I +

aVF +

aVF -

Quadrant Method

- I I +

aVF -

Negative QRS Complex in aVF Positive QRS Complex in aVF

aVF +

- I I +

aVF +

aVF -

Positive QRS in Lead I

Negative QRS in Lead I

Quadrant method

Is Lead I up or down?

Quadrant Method

- I I +

aVF +

aVF -

Quadrant method

Is aVF up or down?

Quadrant Method

- I I +

aVF +

aVF -

Quadrant Method

- I I +

aVF +

aVF -

ERAD LAD

RAD Normal

180 0

-90

90

Quadrant Method

Frontal Plane Axis Pathologies

Quadrant Method

Lead I aVF

Normal Positive (+) Positive (+)

RAD Negative (-) Positive (+)

LAD Positive (+) Negative (-)

ERAD Negative (-) Negative (-)

If all else fails…

That’s It