thaler chapter 1

The 12 Views of the Heart

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Leads II, III, and aVF are called the inferior leads because they most effectively view the inferior surface of the heart. The inferior surface, or wall, of the heart is an anatomic term for the bottom of the heart, the portion that rests on the diaphragm. Leads I and aVL are often called the left lateral leads because they have the best view of the left lateral wall of the heart. aVR is a loner among the limb leads. It is the only true right-sided limb lead . Now is as good a time as any to memorize these six leads and their angles.

Angle

Lead

Inferior Leads

+60°

Lead II

+120°

Lead III

+90°

Lead aVF

III

II

aVF

Left Lateral Leads

aVL

Lead I

+0°

I

Lead aVL

–30°

Right-sided Lead

aVR

Lead aVR

–150°

Of six limb leads, three are standard (I, II, and III), and three are aug- mented (aVR, aVL, and aVF). Each lead views the heart from its own particular angle of orientation.